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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-15 16:27:18 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-15 16:27:18 +0000 |
commit | f7f20c3f5e0be02585741f5f54d198689ccd7866 (patch) | |
tree | 190d5e080f6cbcc40560b0ceaccfd883cb3faa01 /source | |
parent | Initial commit. (diff) | |
download | rsyslog-doc-f7f20c3f5e0be02585741f5f54d198689ccd7866.tar.xz rsyslog-doc-f7f20c3f5e0be02585741f5f54d198689ccd7866.zip |
Adding upstream version 8.2402.0+dfsg.upstream/8.2402.0+dfsg
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'source')
371 files changed, 45177 insertions, 0 deletions
diff --git a/source/.conf.py.swp b/source/.conf.py.swp Binary files differnew file mode 100644 index 0000000..a04f13c --- /dev/null +++ b/source/.conf.py.swp diff --git a/source/_ext/edit_on_github.py b/source/_ext/edit_on_github.py new file mode 100644 index 0000000..a8d22c1 --- /dev/null +++ b/source/_ext/edit_on_github.py @@ -0,0 +1,43 @@ +""" +Sphinx extension to add ReadTheDocs-style "Edit on GitHub" links to the +sidebar. + +Loosely based on https://github.com/astropy/astropy/pull/347 +""" + +import os +import warnings + + +__licence__ = 'BSD (3 clause)' + + +def get_github_url(app, view, path): + return 'https://github.com/{project}/{view}/{branch}/source/{path}'.format( + project=app.config.edit_on_github_project, + view=view, + branch=app.config.edit_on_github_branch, + path=path) + + +def html_page_context(app, pagename, templatename, context, doctree): + if templatename != 'page.html': + return + + if not app.config.edit_on_github_project: + warnings.warn("edit_on_github_project not specified") + return + + path = os.path.relpath(doctree.get('source'), app.builder.srcdir) + show_url = get_github_url(app, 'blob', path) + edit_url = get_github_url(app, 'edit', path) + + context['show_on_github_url'] = show_url + context['edit_on_github_url'] = edit_url + + +def setup(app): + app.add_config_value('edit_on_github_project', '', True) + app.add_config_value('edit_on_github_branch', 'master', True) + app.connect('html-page-context', html_page_context) + diff --git a/source/_ext/edit_on_github.pyc b/source/_ext/edit_on_github.pyc Binary files differnew file mode 100644 index 0000000..2d9b422 --- /dev/null +++ b/source/_ext/edit_on_github.pyc diff --git a/source/_static/rsyslog.css b/source/_static/rsyslog.css new file mode 100644 index 0000000..7c9c858 --- /dev/null +++ b/source/_static/rsyslog.css @@ -0,0 +1,543 @@ +/* + * basic.css + * ~~~~~~~~~ + * + * Sphinx stylesheet -- basic theme. + * + * :copyright: Copyright 2007-2013 by the Sphinx team, see AUTHORS. + * :license: BSD, see LICENSE for details. + * + */ + +/* -- main layout ----------------------------------------------------------- */ + +div.clearer { + clear: both; +} + +/* -- relbar ---------------------------------------------------------------- */ + +div.related { + width: 100%; + font-size: 90%; +} + +div.related h3 { + display: none; +} + +div.related ul { + margin: 0; + padding: 0 0 0 10px; + list-style: none; +} + +div.related li { + display: inline; +} + +div.related li.right { + float: right; + margin-right: 5px; +} + +/* -- sidebar --------------------------------------------------------------- */ + +div.sphinxsidebarwrapper { + padding: 10px 5px 0 10px; +} + +div.sphinxsidebar { + float: left; + width: {{ theme_sidebarwidth|toint }}px; + margin-left: -100%; + font-size: 90%; +} + +div.sphinxsidebar ul { + list-style: none; +} + +div.sphinxsidebar ul ul, +div.sphinxsidebar ul.want-points { + margin-left: 20px; + list-style: square; +} + +div.sphinxsidebar ul ul { + margin-top: 0; + margin-bottom: 0; +} + +div.sphinxsidebar form { + margin-top: 10px; +} + +div.sphinxsidebar input { + border: 1px solid #98dbcc; + font-family: sans-serif; + font-size: 1em; +} + +div.sphinxsidebar #searchbox input[type="text"] { + width: 170px; +} + +div.sphinxsidebar #searchbox input[type="submit"] { + width: 30px; +} + +img { + border: 0; +} + +/* -- search page ----------------------------------------------------------- */ + +ul.search { + margin: 10px 0 0 20px; + padding: 0; +} + +ul.search li { + padding: 5px 0 5px 20px; + background-image: url(file.png); + background-repeat: no-repeat; + background-position: 0 7px; +} + +ul.search li a { + font-weight: bold; +} + +ul.search li div.context { + color: #888; + margin: 2px 0 0 30px; + text-align: left; +} + +ul.keywordmatches li.goodmatch a { + font-weight: bold; +} + +/* -- index page ------------------------------------------------------------ */ + +table.contentstable { + width: 90%; +} + +table.contentstable p.biglink { + line-height: 150%; +} + +a.biglink { + font-size: 1.3em; +} + +span.linkdescr { + font-style: italic; + padding-top: 5px; + font-size: 90%; +} + +/* -- general index --------------------------------------------------------- */ + +table.indextable { + width: 100%; +} + +table.indextable td { + text-align: left; + vertical-align: top; +} + +table.indextable dl, table.indextable dd { + margin-top: 0; + margin-bottom: 0; +} + +table.indextable tr.pcap { + height: 10px; +} + +table.indextable tr.cap { + margin-top: 10px; + background-color: #f2f2f2; +} + +img.toggler { + margin-right: 3px; + margin-top: 3px; + cursor: pointer; +} + +div.modindex-jumpbox { + border-top: 1px solid #ddd; + border-bottom: 1px solid #ddd; + margin: 1em 0 1em 0; + padding: 0.4em; +} + +div.genindex-jumpbox { + border-top: 1px solid #ddd; + border-bottom: 1px solid #ddd; + margin: 1em 0 1em 0; + padding: 0.4em; +} + +/* -- general body styles --------------------------------------------------- */ + +a.headerlink { + visibility: hidden; +} + +h1:hover > a.headerlink, +h2:hover > a.headerlink, +h3:hover > a.headerlink, +h4:hover > a.headerlink, +h5:hover > a.headerlink, +h6:hover > a.headerlink, +dt:hover > a.headerlink { + visibility: visible; +} + +div.body p.caption { + text-align: inherit; +} + +div.body td { + text-align: left; +} + +.field-list ul { + padding-left: 1em; +} + +.first { + margin-top: 0 !important; +} + +p.rubric { + margin-top: 30px; + font-weight: bold; +} + +img.align-left, .figure.align-left, object.align-left { + clear: left; + float: left; + margin-right: 1em; +} + +img.align-right, .figure.align-right, object.align-right { + clear: right; + float: right; + margin-left: 1em; +} + +img.align-center, .figure.align-center, object.align-center { + display: block; + margin-left: auto; + margin-right: auto; +} + +.align-left { + text-align: left; +} + +.align-center { + text-align: center; +} + +.align-right { + text-align: right; +} + +/* -- sidebars -------------------------------------------------------------- */ + +div.sidebar { + margin: 0 0 0.5em 1em; + border: 1px solid #ddb; + padding: 7px 7px 0 7px; + background-color: #ffe; + width: 40%; + float: right; +} + +p.sidebar-title { + font-weight: bold; +} + +/* -- topics ---------------------------------------------------------------- */ + +div.topic { + border: 1px solid #ccc; + padding: 7px 7px 0 7px; + margin: 10px 0 10px 0; +} + +p.topic-title { + font-size: 1.1em; + font-weight: bold; + margin-top: 10px; +} + +/* -- admonitions ----------------------------------------------------------- */ + +div.admonition { + margin-top: 10px; + margin-bottom: 10px; + padding: 7px; +} + +div.admonition dt { + font-weight: bold; +} + +div.admonition dl { + margin-bottom: 0; +} + +p.admonition-title { + margin: 0px 10px 5px 0px; + font-weight: bold; +} + +div.body p.centered { + text-align: center; + margin-top: 25px; +} + +/* -- tables ---------------------------------------------------------------- */ + +table.docutils { + border: 0; + border-collapse: collapse; +} + +table.docutils td, table.docutils th { + padding: 1px 8px 1px 5px; + border-top: 0; + border-left: 0; + border-right: 0; + border-bottom: 1px solid #aaa; +} + +table.field-list td, table.field-list th { + border: 0 !important; +} + +table.footnote td, table.footnote th { + border: 0 !important; +} + +th { + text-align: left; + padding-right: 5px; +} + +table.citation { + border-left: solid 1px gray; + margin-left: 1px; +} + +table.citation td { + border-bottom: none; +} + +/* -- other body styles ----------------------------------------------------- */ + +ol.arabic { + list-style: decimal; +} + +ol.loweralpha { + list-style: lower-alpha; +} + +ol.upperalpha { + list-style: upper-alpha; +} + +ol.lowerroman { + list-style: lower-roman; +} + +ol.upperroman { + list-style: upper-roman; +} + +dl { + margin-bottom: 15px; +} + +dd p { + margin-top: 0px; +} + +dd ul, dd table { + margin-bottom: 10px; +} + +dd { + margin-top: 3px; + margin-bottom: 10px; + margin-left: 30px; +} + +dt:target, .highlighted { + background-color: #fbe54e; +} + +dl.glossary dt { + font-weight: bold; + font-size: 1.1em; +} + +.field-list ul { + margin: 0; + padding-left: 1em; +} + +.field-list p { + margin: 0; +} + +.optional { + font-size: 1.3em; +} + +.versionmodified { + font-style: italic; +} + +.system-message { + background-color: #fda; + padding: 5px; + border: 3px solid red; +} + +.footnote:target { + background-color: #ffa; +} + +.line-block { + display: block; + margin-top: 1em; + margin-bottom: 1em; +} + +.line-block .line-block { + margin-top: 0; + margin-bottom: 0; + margin-left: 1.5em; +} + +.guilabel, .menuselection { + font-family: sans-serif; +} + +.accelerator { + text-decoration: underline; +} + +.classifier { + font-style: oblique; +} + +abbr, acronym { + border-bottom: dotted 1px; + cursor: help; +} + +/* Add extra space between parameter sections */ +div.section { + margin-top: 30px; +} + + + +/* -- code displays --------------------------------------------------------- */ + +pre { + overflow: auto; + overflow-y: hidden; /* fixes display issues on Chrome browsers */ +} + +td.linenos pre { + padding: 5px 0px; + border: 0; + background-color: transparent; + color: #aaa; +} + +table.highlighttable { + margin-left: 0.5em; +} + +table.highlighttable td { + padding: 0 0.5em 0 0.5em; +} + +tt.descname { + background-color: transparent; + font-weight: bold; + font-size: 1.2em; +} + +tt.descclassname { + background-color: transparent; +} + +tt.xref, a tt { + background-color: transparent; + font-weight: bold; +} + +h1 tt, h2 tt, h3 tt, h4 tt, h5 tt, h6 tt { + background-color: transparent; +} + +.viewcode-link { + float: right; +} + +.viewcode-back { + float: right; + font-family: sans-serif; +} + +div.viewcode-block:target { + margin: -1px -10px; + padding: 0 10px; +} + +/* -- math display ---------------------------------------------------------- */ + +img.math { + vertical-align: middle; +} + +div.body div.math p { + text-align: center; +} + +span.eqno { + float: right; +} + +/* -- printout stylesheet --------------------------------------------------- */ + +@media print { + div.document, + div.documentwrapper, + div.bodywrapper { + margin: 0 !important; + width: 100%; + } + + div.sphinxsidebar, + div.related, + div.footer, + #top-link { + display: none; + } +} diff --git a/source/_templates/sourcelink.html b/source/_templates/sourcelink.html new file mode 100644 index 0000000..5250a4e --- /dev/null +++ b/source/_templates/sourcelink.html @@ -0,0 +1,12 @@ +{%- if show_source and has_source and sourcename %} + <h3>{{ _('This Page') }}</h3> + <ul class="this-page-menu"> + <li><a href="{{ pathto('_sources/' + sourcename, true)|e }}" + rel="nofollow">{{ _('Show Source') }}</a></li> + {%- if edit_on_github_url %} + <li><a href="{{ edit_on_github_url }}" + rel="nofollow">{{ _('Edit on GitHub') }}</a></li> + {%- endif %} + </ul> +{%- endif %} + diff --git a/source/community.rst b/source/community.rst new file mode 100644 index 0000000..c6eb083 --- /dev/null +++ b/source/community.rst @@ -0,0 +1,37 @@ +Community Resources +=================== + +You can also browse the following online resources: + +- the `rsyslog wiki <http://wiki.rsyslog.com/>`_, a community resource + which includes `rsyslog configuration + examples <http://wiki.rsyslog.com/index.php/Configuration_Samples>`_ +- `rsyslog discussion forum - use this for technical + support <http://kb.monitorware.com/rsyslog-f40.html>`_ +- `rsyslog video tutorials <http://www.rsyslog.com/Topic8.phtml>`_ +- `rsyslog FAQ <http://www.rsyslog.com/Topic3.phtml>`_ +- `syslog device configuration + guide <http://www.monitorware.com/en/syslog-enabled-products/>`_ + (off-site) +- `deutsches rsyslog + forum <http://kb.monitorware.com/rsyslog-f49.html>`_ (forum in German + language) + +And don't forget about the `rsyslog mailing +list <http://lists.adiscon.net/mailman/listinfo/rsyslog>`_. If you are +interested in the "backstage", you may find +`Rainer <https://rainer.gerhards.net/>`_'s +`blog <https://rainer.gerhards.net/>`_ an interesting read (filter on +syslog and rsyslog tags). Or meet `Rainer Gerhards at +Facebook <http://www.facebook.com/people/Rainer-Gerhards/1349393098>`_. +If you would like to use rsyslog source code inside your open source +project, you can do that without any restriction as long as your license +is GPLv3 compatible. If your license is incompatible to GPLv3, you may +even be still permitted to use rsyslog source code. However, then you +need to look at the way `rsyslog is licensed <licensing.html>`_. + +Feedback is always welcome, but if you have a support question, please +do not mail Rainer directly (`why not? <free_support.html>`_) - use the +`rsyslog mailing +list <http://lists.adiscon.net/mailman/listinfo/rsyslog>`_ or `github issue +tracker <https://github.com/rsyslog/rsyslog/issues>`_ instead. diff --git a/source/compatibility/index.rst b/source/compatibility/index.rst new file mode 100644 index 0000000..073c907 --- /dev/null +++ b/source/compatibility/index.rst @@ -0,0 +1,12 @@ +Compatibility +============= + +.. toctree:: + :glob: + + v8compatibility + v7compatibility + v6compatibility + v5compatibility + v4compatibility + v3compatibility diff --git a/source/compatibility/v3compatibility.rst b/source/compatibility/v3compatibility.rst new file mode 100644 index 0000000..502ca64 --- /dev/null +++ b/source/compatibility/v3compatibility.rst @@ -0,0 +1,260 @@ +Compatibility Notes for rsyslog v3 +================================== + +*Written by* `Rainer Gerhards <http://www.gerhards.net/rainer>`_ +*(2008-03-28)* + +Rsyslog aims to be a drop-in replacement for sysklogd. However, version +3 has some considerable enhancements, which lead to some backward +compatibility issues both in regard to sysklogd and rsyslog v1 and v2. +Most of these issues are avoided by default by not specifying the -c +option on the rsyslog command line. That will enable +backwards-compatibility mode. However, please note that things may be +suboptimal in backward compatibility mode, so the advise is to work +through this document, update your rsyslog.conf, remove the no longer +supported startup options and then add -c3 as the first option to the +rsyslog command line. That will enable native mode. + +Please note that rsyslogd helps you during that process by logging +appropriate messages about compatibility mode and +backwards-compatibility statements automatically generated. You may +want your syslogd log for those. They immediately follow rsyslogd's +startup message. + +Inputs +------ + +With v2 and below, inputs were automatically started together with +rsyslog. In v3, inputs are optional! They come in the form of plug-in +modules. **At least one input module must be loaded to make rsyslog do +any useful work.** The config file directives doc briefly lists which +config statements are available by which modules. + +It is suggested that input modules be loaded in the top part of the +config file. Here is an example, also highlighting the most important +modules: + +:: + + $ModLoad immark # provides --MARK-- message capability + $ModLoad imudp # provides UDP syslog reception + $ModLoad imtcp # provides TCP syslog reception + $ModLoad imgssapi # provides GSSAPI syslog reception + $ModLoad imuxsock # provides support for local system logging (e.g. via logger command) + $ModLoad imklog # provides kernel logging support (previously done by rklogd) + +Command Line Options +-------------------- + +A number of command line options have been removed. New config file +directives have been added for them. The -h and -e option have been +removed even in compatibility mode. They are ignored but an informative +message is logged. Please note that -h was never supported in v2, but +was silently ignored. It disappeared some time ago in the final v1 +builds. It can be replaced by applying proper filtering inside +syslog.conf. + +-c option / Compatibility Mode +------------------------------ + +The -c option is new and tells rsyslogd about the desired backward +compatibility mode. It must always be the first option on the command +line, as it influences processing of the other options. To use the +rsyslog v3 native interface, specify -c3. To use compatibility mode , +either do not use -c at all or use -c<vers> where vers is the rsyslog +version that it shall be compatible to. Use -c0 to be command-line +compatible to sysklogd. + +Please note that rsyslogd issues warning messages if the -c3 command +line option is not given. This is to alert you that your are running in +compatibility mode. Compatibility mode interferes with your rsyslog.conf +commands and may cause some undesired side-effects. It is meant to be +used with a plain old rsyslog.conf - if you use new features, things +become messy. So the best advise is to work through this document, +convert your options and config file and then use rsyslog in native +mode. In order to aid you in this process, rsyslog logs every +compatibility-mode config file directive it has generated. So you can +simply copy them from your logfile and paste them to the config. + +-e Option +--------- + +This option is no longer supported, as the "last message repeated n +times" feature is now turned off by default. We changed this default +because this feature is causing a lot of trouble and we need to make it +either go away or change the way it works. For more information, please +see our dedicated `forum thread on "last message repeated n +times" <http://www.rsyslog.com/PNphpBB2-viewtopic-p-1130.phtml>`_. This +thread also contains information on how to configure rsyslogd so that it +continues to support this feature (as long as it is not totally +removed). + +-m Option +--------- + +The -m command line option is emulated in compatibility mode. To replace +it, use the following config directives (compatibility mode +auto-generates them): + +:: + + $ModLoad immark + $MarkMessagePeriod 1800 # 30 minutes + +-r Option +--------- + +Is no longer available in native mode. However, it is understood in +compatibility mode (if no -c option is given). Use the ``$UDPSeverRun +<port>`` config file directives. You can now also set the local address +the server should listen to via ``$UDPServerAddress <ip>`` config +directive. + +The following example configures an UDP syslog server at the local +address 192.0.2.1 on port 514: + +:: + + $ModLoad imudp + $UDPServerAddress 192.0.2.1 # this MUST be before the $UDPServerRun directive! + $UDPServerRun 514 + +``$UDPServerAddress \*`` means listen on all local interfaces. This is the +default if no directive is specified. + +Please note that now multiple listeners are supported. For example, you +can do the following: + +:: + + $ModLoad imudp + $UDPServerAddress 192.0.2.1 # this MUST be before the $UDPServerRun directive! + $UDPServerRun 514 + $UDPServerAddress \* # all local interfaces + $UDPServerRun 1514 + +These config file settings run two listeners: one at 192.0.2.1:514 and +one on port 1514, which listens on all local interfaces. + +Default port for UDP (and TCP) Servers +-------------------------------------- + +Please note that with pre-v3 rsyslogd, a service database lookup was +made when a UDP server was started and no port was configured. Only if +that failed, the IANA default of 514 was used. For TCP servers, this +lookup was never done and 514 always used if no specific port was +configured. For consistency, both TCP and UDP now use port 514 as +default. If a lookup is desired, you need to specify it in the "Run" +directive, e.g. "*$UDPServerRun syslog*\ ". + +klogd +----- + +klogd has (finally) been replaced by a loadable input module. To enable +klogd functionality, do + +:: + + $ModLoad imklog + +Note that this can not be handled by the compatibility layer, as klogd +was a separate binary. A limited set of klogd command line settings is +now supported via rsyslog.conf. That set of configuration directives is +to be expanded. + +Output File Syncing +------------------- + +Rsyslogd tries to keep as compatible to stock syslogd as possible. As +such, it retained stock syslogd's default of syncing every file write if +not specified otherwise (by placing a dash in front of the output file +name). While this was a useful feature in past days where hardware was +much less reliable and UPS seldom, this no longer is useful in today's +world. Instead, the syncing is a high performance hit. With it, rsyslogd +writes files around 50 **times** slower than without it. It also affects +overall system performance due to the high IO activity. In rsyslog v3, +syncing has been turned off by default. This is done via a specific +configuration directive + +:: + $ActionFileEnableSync on/off + +which is off by +default. So even if rsyslogd finds sync selector lines, it ignores them +by default. In order to enable file syncing, the administrator must +specify ``$ActionFileEnableSync on`` at the top of rsyslog.conf. This +ensures that syncing only happens in some installations where the +administrator actually wanted that (performance-intense) feature. In the +fast majority of cases (if not all), this dramatically increases +rsyslogd performance without any negative effects. + +Output File Format +------------------ + +Rsyslog supports high precision RFC 3339 timestamps and puts these into +local log files by default. This is a departure from previous syslogd +behaviour. We decided to sacrifice some backward-compatibility in an +effort to provide a better logging solution. Rsyslog has been supporting +the high-precision timestamps for over three years as of this writing, +but nobody used them because they were not default (one may also assume +that most people didn't even know about them). Now, we are writing the +great high-precision time stamps, which greatly aid in getting the right +sequence of logging events. If you do not like that, you can easily turn +them off by placing + +:: + + $ActionFileDefaultTemplate RSYSLOG_TraditionalFileFormat + +right at the start of your rsyslog.conf. This will use the previous +format. Please note that the name is case-sensitive and must be +specified exactly as shown above. Please also note that you can of +course use any other format of your liking. To do so, simply specify the +template to use or set a new default template via the +$ActionFileDefaultTemplate directive. Keep in mind, though, that +templates must be defined before they are used. + +Keep in mind that when receiving messages from remote hosts, the +timestamp is just as precise as the remote host provided it. In most +cases, this means you will only a receive a standard timestamp with +second precision. If rsyslog is running at the remote end, you can +configure it to provide high-precision timestamps (see below). + +Forwarding Format +----------------- + +When forwarding messages to remote syslog servers, rsyslogd by default +uses the plain old syslog format with second-level resolution inside the +timestamps. We could have made it emit high precision timestamps. +However, that would have broken almost all receivers, including earlier +versions of rsyslog. To avoid this hassle, high-precision timestamps +need to be explicitly enabled. To make this as painless as possible, +rsyslog comes with a canned template that contains everything necessary. + To enable high-precision timestamps, just use: + +:: + + $ActionForwardDefaultTemplate RSYSLOG_ForwardFormat # for plain TCP and UDP + $ActionGSSForwardDefaultTemplate RSYSLOG_ForwardFormat # for GSS-API + +And, of course, you can always set different forwarding formats by just +specifying the right template. + +If you are running in a system with only rsyslog 3.12.5 and above in the +receiver roles, it is suggested to add one (or both) of the above +statements to the top of your rsyslog.conf (but after the $ModLoad's!) - +that will enable you to use the best in timestamp support available. +Please note that when you use this format with other receivers, they +will probably become pretty confused and not detect the timestamp at +all. In earlier rsyslog versions, for example, that leads to duplication +of timestamp and hostname fields and disables the detection of the +original hostname in a relayed/NATed environment. So use the new format +with care. + +Queue Modes for the Main Message Queue +-------------------------------------- + +Either "FixedArray" or "LinkedList" is recommended. "Direct" is +available, but should not be used except for a very good reason +("Direct" disables queueing and will potentially lead to message loss on +the input side). diff --git a/source/compatibility/v4compatibility.rst b/source/compatibility/v4compatibility.rst new file mode 100644 index 0000000..ddbce3e --- /dev/null +++ b/source/compatibility/v4compatibility.rst @@ -0,0 +1,132 @@ +Compatibility Notes for rsyslog v4 +================================== + +*Written by* `Rainer Gerhards <http://www.gerhards.net/rainer>`_ +*(2009-07-15)* + +The changes introduced in rsyslog v4 are numerous, but not very +intrusive. This document describes things to keep in mind when moving +from v3 to v4. It does not list enhancements nor does it talk about +compatibility concerns introduced by v3 (for this, see the `rsyslog v3 +compatibility notes <v3compatibility.html>`_). + +HUP processing +-------------- + +With v3 and below, rsyslog used the traditional HUP behaviour. That +meant that all output files are closed and the configuration file is +re-read and the new configuration applied. + +With a program as simple and static as sysklogd, this was not much of an +issue. The most important config settings (like udp reception) of a +traditional syslogd can not be modified via the configuration file. So a +config file reload only meant setting up a new set of filters. It also +didn't account as problem that while doing so messages may be lost - +without any threading and queuing model, a traditional syslogd will +potentially always loose messages, so it is irrelevant if this happens, +too, during the short config re-read phase. + +In rsyslog, things are quite different: the program is more or less a +framework into which loadable modules are loaded as needed for a +particular configuration. The software that will actually be running is +tailored via the config file. Thus, a re-read of the config file +requires a full, very heavy restart, because the software actually +running with the new config can be totally different from what ran with +the old config. + +Consequently, the traditional HUP is a very heavy operation and may even +cause some data loss because queues must be shut down, listeners stopped +and so on. Some of these operations (depending on their configuration) +involve intentional message loss. The operation also takes up a lot of +system resources and needs quite some time (maybe seconds) to be +completed. During this restart period, the syslog subsystem is not fully +available. + +From the software developer's point of view, the full restart done by a +HUP is rather complex, especially if user-timeout limits set on action +completion are taken into consideration (for those in the know: at the +extreme ends this means we need to cancel threads as a last resort, but +than we need to make sure that such cancellation does not happen at +points where it would be fatal for a restart). A regular restart, where +the process is actually terminated, is much less complex, because the +operating system does a full cleanup after process termination, so +rsyslogd does not need to take care for exotic cleanup cases and leave +that to the OS. In the end result, restart-type HUPs clutter the code, +increase complexity (read: add bugs) and cost performance. + +On the contrary, a HUP is typically needed for log rotation, and the +real desire is to close files. This is a non-disruptive and very +lightweight operation. + +Many people have said that they are used to HUP the syslogd to apply +configuration changes. This is true, but it is questionable if that +really justifies all the cost that comes with it. After all, it is the +difference between typing + +:: + + $ kill -HUP `cat /var/run/rsyslogd.pid` + +versus + +:: + + $ /etc/init.d/rsyslog restart + +Semantically, both is mostly the same thing. The only difference is that +with the restart command rsyslogd can spit config error message to +stderr, so that the user is able to see any problems and fix them. With +a HUP, we do not have access to stderr and thus can log error messages +only to their configured destinations; experience tells that most users +will never find them there. What, by the way, is another strong argument +against restarting rsyslogd by HUPing it. + +So a restart via HUP is not strictly necessary and most other daemons +require that a restart command is typed in if a restart is required. + +Rsyslog will follow this paradigm in the next versions, resulting in +many benefits. In v4, we provide some support for the old-style +semantics. We introduced a setting $HUPisRestart which may be set to +"on" (traditional, heavy operation) or "off" (new, lightweight "file +close only" operation). The initial versions had the default set to +traditional behavior, but starting with 4.5.1 we are now using the new +behavior as the default. + +Most importantly, **this may break some scripts**, but my sincere belief +is that there are very few scripts that automatically **change** +rsyslog's config and then do a HUP to reload it. Anyhow, if you have +some of these, it may be a good idea to change them now instead of +turning restart-type HUPs on. Other than that, one mainly needs to +change the habit of how to restart rsyslog after a configuration change. + +**Please note that restart-type HUP is deprecated and will go away in +rsyslog v5.** So it is a good idea to become ready for the new version +now and also enjoy some of the benefits of the "real restart", like the +better error-reporting capability. + +Note that code complexity reduction (and thus performance improvement) +needs the restart-type HUP code to be removed, so these changes can (and +will) only happen in version 5. + +outchannels +----------- + +Note: as always documented, outchannels are an experimental feature that +may be removed and/or changed in the future. There is one concrete +change done starting with 4.6.7: let's assume an outchannel "mychannel" +was defined. Then, this channel could be used inside an + +\*.\* $mychannel + +This is still supported and will remain to be +supported in v4. However, there is a new variant which explicitly tells +this is to be handled by omfile. This new syntax is as follows: + +\*.\* :omfile:$mychannel + +Note that future versions, specifically +starting with v6, the older syntax is no longer supported. So users are +strongly advised to switch to the new syntax. As an aid to the +conversion process, rsyslog 4.7.4 and above issue a warning message if +the old-style directive is seen -- but still accept the old syntax +without any problems. diff --git a/source/compatibility/v5compatibility.rst b/source/compatibility/v5compatibility.rst new file mode 100644 index 0000000..c7e1865 --- /dev/null +++ b/source/compatibility/v5compatibility.rst @@ -0,0 +1,49 @@ +Compatibility Notes for rsyslog v5 +================================== + +*Written by* `Rainer Gerhards <http://www.gerhards.net/rainer>`_ +*(2009-07-15)* + +The changes introduced in rsyslog v5 are numerous, but not very +intrusive. This document describes things to keep in mind when moving +from v4 to v5. It does not list enhancements nor does it talk about +compatibility concerns introduced by earlier versions (for this, see +their respective compatibility documents). + +HUP processing +-------------- + +The $HUPisRestart directive is supported by some early v5 versions, but +has been removed in 5.1.3 and above. That means that restart-type HUP +processing is no longer available. This processing was redundant and had +a lot a drawbacks. For details, please see the `rsyslog v4 compatibility +notes <v4compatibility.html>`_ which elaborate on the reasons and the +(few) things you may need to change. + +Please note that starting with 5.8.11 HUP will also requery the local +hostname. + +Queue on-disk format +-------------------- + +The queue information file format has been changed. When upgrading from +v4 to v5, make sure that the queue is emptied and no on-disk structure +present. We did not go great length in understanding the old format, as +there was too little demand for that (and it being quite some effort if +done right). + +Queue Worker Thread Shutdown +---------------------------- + +Previous rsyslog versions had the capability to "run" on zero queue +worker if no work was required. This was done to save a very limited +number of resources. However, it came at the price of great complexity. +In v5, we have decided to let a minimum of one worker run all the time. +The additional resource consumption is probably not noticeable at all, +however, this enabled us to do some important code cleanups, resulting +in faster and more reliable code (complex code is hard to maintain and +error-prone). From the regular user's point of view, this change should +be barely noticeable. I am including the note for expert users, who will +notice it in rsyslog debug output and other analysis tools. So it is no +error if each queue in non-direct mode now always runs at least one +worker thread. diff --git a/source/compatibility/v6compatibility.rst b/source/compatibility/v6compatibility.rst new file mode 100644 index 0000000..1023acc --- /dev/null +++ b/source/compatibility/v6compatibility.rst @@ -0,0 +1,230 @@ +Compatibility Notes for rsyslog v6 +================================== + +This document describes things to keep in mind when moving from v5 to v6. It +does not list enhancements nor does it talk about compatibility concerns introduced +by earlier versions (for this, see their respective compatibility documents). Its focus +is primarily on what you need to know if you used a previous version and want to use the +current one without hassle. + +Version 6 offers a better config language and some other improvements. +As the config system has many ties into the rsyslog engine AND all plugins, +the changes are somewhat intrusive. Note, however, that core processing has +not been changed much in v6 and will not. So once the configuration is loaded, +the stability of v6 is quite comparable to v5. + +Property "pri-text" +------------------- +Traditionally, this property did not only return the textual form +of the pri ("local0.err"), but also appended the numerical value to it +("local0.err<133>"). This sounds odd and was left unnoticed for some years. +In October 2011, this odd behaviour was brought up on the rsyslog mailing list +by Gregory K. Ruiz-Ade. Code review showed that the behaviour was intentional, +but no trace of what the intention was when it was introduced could be found. +The documentation was also unclear, it said no numerical value was present, +but the samples had it. We agreed that the additional numerical value is +of disadvantage. We also guessed that this property is very rarely being used, +otherwise the problem should have been raised much earlier. However, we +didn't want to change behaviour in older builds. So v6 was set to clean up +the situation. In v6, text-pri will always return the textual part only +("local0.err") and the numerical value will not be contained any longer inside +the string. If you actually need that value, it can fairly easily be added +via the template system. +**If you have used this property previously and relied on the numerical +part, you need to update your rsyslog configuration files.** + +Plugin ABI +---------- +The plugin interface has considerably been changed to support the new +config language. All plugins need to be upgraded. This usually does not require +much coding. However, if the new config language shall be supported, more +changes must be made to plugin code. All project-supported plugins have been +upgraded, so this compatibility issue is only of interest for you if you have +custom plugins or use some user-contributed plugins from the rsyslog project +that are not maintained by the project itself (omoracle is an example). Please +expect some further plugin instability during the initial v6 releases. + +RainerScript based rsyslog.conf +------------------------------- +A better config format was the main release target for rsyslog v6. It comes in the +flavor of so-called RainerScript +`(why the name RainerScript?) +<https://rainer.gerhards.net/2008/02/introducing-rainerscript-and-some.html>`_ +RainerScript supports legacy syslog.conf format, much as you know it +from other syslogds (like sysklogd or the BSD syslogd) as well as previous versions +of rsyslog. Initial work on RainerScript began in v4, and the if-construct was already +supported in v4 and v5. Version 6 has now taken this further. After long discussions we +decided to use the legacy format as a basis, and lightly extend it by native RainerScript +constructs. The main goal was to make sure that previous knowledge and config systems +could still be used while offering a much more intuitive and powerful way of configuring +rsyslog. + +RainerScript has been implemented from scratch and with new tools (flex/bison, for those in the +know). Starting with 6.3.3, this new config file processor replaces the legacy one. Note that +the new processor handles all formats, extended RainerScript as well as legacy syslog.conf format. +There are some legacy construct that were especially hard to translate. You'll read about them in +other parts of this document (especially outchannels, which require a format change). + +In v6, all legacy formats are supported. In the long term, we may remove some of the ugly +rsyslog-specific constructs. Good candidates are all configuration commands starting with +a dollar sign, like "$ActionFileDefaultTemplate"). However, this will not be the case before +rsyslog v7 or (much more likely) v8/9. Right now, you also need to use these commands, because +not all have already been converted to the new RainerScript format. + +In 6.3.3, the new parser is used, but almost none of the extended RainerScript capabilities +are available. They will incrementally be introduced with the following releases. Note that for +some features (most importantly if-then-else nested blocks), the v6 core engine is not +capable enough. It is our aim to provide a much better config language to as many rsyslog +users as quickly as possible. As such, we refrain from doing big engine changes in v6. This +in turn means we cannot introduce some features into RainerScript that we really want to see. +These features will come up with rsyslog v7, which will have even better flow control +capabilities inside the core engine. Note that v7 will fully support v6 RainerScript. +Let us also say that the v6 version is not a low-end quick hack: it offers full-fledged +syslog message processing control, capable of doing the best you can find inside the +industry. We just say that v7 will come up with even more advanced capabilities. + +Please note that we tried hard to make the RainerScript parser compatible with +all legacy config files. However, we may have failed in one case or another. So if you +experience problems during config processing, chances are there may be a problem +on the rsyslog side. In that case, please let us know. + +Please see the +`blog post about rsyslog 6.3.3 config format +<https://rainer.gerhards.net/2011/07/rsyslog-633-config-format-improvements.html>`_ +for details of what is currently supported. + +compatibility mode +------------------ +Compatibility mode (specified via -c option) has been removed. This was a migration aid from +sysklogd and very early versions of rsyslog. As all major distros now have rsyslog as their +default, and thus ship rsyslog-compliant config files, there is no longer a need for +compatibility mode. Removing it provides easier to maintain code. Also, practice has shown +that many users were confused by compatibility mode (and even some package maintainers got +it wrong). So this not only cleans up the code but rather removes a frequent source of +error. + +It must be noted, though, that this means rsyslog is no longer a 100% drop-in replacement +for sysklogd. If you convert an extremely old system, you need to checks its config and +probably need to apply some very mild changes to the config file. + +abort on config errors +---------------------- +Previous versions accepted some malformedness inside the config file without aborting. This +could lead to some uncertainty about which configuration was actually running. In v6 there +are some situations where config file errors can not be ignored. In these cases rsyslog +emits error messages to stderr, and then exists with a non-zero exit code. It is important +to check for those cases as this means log data is potentially lost. +Please note that +the root problem is the same for earlier versions as well. With them, it was just harder +to spot why things went wrong (and if at all). + +Default Batch Sizes +------------------- +Due to their positive effect on performance and comparatively low overhead, +default batch sizes have been increased. Starting with 6.3.4, the action queues +have a default batch size of 128 messages. + +Default action queue enqueue timeout +------------------------------------ +This timeout previously was 2 seconds, and has been reduced to 50ms (starting with 6.5.0). This change +was made as a long timeout will caused delays in the associated main queue, something +that was quite unexpected to users. Now, this can still happen, but the effect is much +less harsh (but still considerable on a busy system). Also, 50ms should be fairly enough +for most output sources, except when they are really broken (like network disconnect). If +they are really broken, even a 2second timeout does not help, so we hopefully get the best +of both worlds with the new timeout. A specific timeout can of course still be configured, +it is just the timeout that changed. + +outchannels +----------- +Outchannels are a to-be-removed feature of rsyslog, at least as far as the config +syntax is concerned. Nevertheless, v6 still supports it, but a new syntax is required +for the action. Let's assume your outchannel is named "channel". The previous syntax was + +:: + + *.* $channel + +This was deprecated in v5 and no longer works in v6. Instead, you need to specify + +:: + + *.* :omfile:$channel + +Note that this syntax is available starting with rsyslog v4. It is important to keep on your +mind that future versions of rsyslog will require different syntax and/or drop outchannel support +completely. So if at all possible, avoid using this feature. If you must use it, be prepared for +future changes and watch announcements very carefully. + +ompipe default template +----------------------- +Starting with 6.5.0, ompipe does no longer use the omfile default template. +Instead, the default template must be set via the module load statement. +An example is + +:: + + module(load="builtin:ompipe" template="myDefaultTemplate") + +For obvious reasons, the default template must be defined somewhere in +the config file, otherwise errors will happen during the config load +phase. + +omusrmsg +-------- +The omusrmsg module is used to send messages to users. In legacy-legacy +config format (that is the very old sysklogd style), it was sufficient to use +just the user name to call this action, like in this example: + +:: + + *.* rgerhards + +This format is very ambiguous and causes headache (see +`blog post on omusrmsg <https://rainer.gerhards.net/2011/07/why-omusrmsg-is-evil-and-how-it-is.html>`_ +for details). Thus the format has been superseded by this syntax +(which is legacy format ;-)): + +:: + + *.* :omusrmsg:rgerhards + +That syntax is supported since later subversions of version 4. + +Rsyslog v6 still supports the legacy-legacy format, but in a very strict +sense. For example, if multiple users or templates are given, no spaces +must be included in the action line. For example, this works up to v5, but no +longer in v6: + +:: + + *.* rgerhards, bgerhards + +To fix it in a way that is compatible with pre-v4, use (note the removed space!): + +:: + + *.* rgerhards,bgerhards + +Of course, it probably is better to understand in native v6 format: + +:: + + *.* action(type="omusrmsg" users="rgerhards, bgerhards") + +As you see, here you may include spaces between user names. + +In the long term, legacy-legacy format will most probably totally disappear, +so it is a wise decision to change config files at least to the legacy +format (with ":omusrmsg:" in front of the name). + +Escape Sequences in Script-Based Filters +---------------------------------------- +In v5, escape sequences were very simplistic. Inside a string, "\x" meant +"x" with x being any character. This has been changed so that the usual set of +escapes is supported, must importantly "\n", "\t", "\xhh" (with hh being hex digits) +and "\ooo" with (o being octal digits). So if one of these sequences was used +previously, results are obviously different. However, that should not create any +real problems, because it is hard to envision why someone should have done that +(why write "\n" when you can also write "n"?). + diff --git a/source/compatibility/v7compatibility.rst b/source/compatibility/v7compatibility.rst new file mode 100644 index 0000000..ba6a1de --- /dev/null +++ b/source/compatibility/v7compatibility.rst @@ -0,0 +1,173 @@ +Compatibility Notes for rsyslog v7 +================================== + +This document describes things to keep in mind when moving from v6 to v7. It +does not list enhancements nor does it talk about compatibility concerns +introduced by earlier versions (for this, see their respective compatibility +documents). Its focus is primarily on what you need to know if you used v6 +and want to use v7 without hassle. + +Version 7 builds on the new config language introduced in v6 and extends it. +Other than v6, it not just only extends the config language, but provides +considerable changes to core elements as well. The result is much more power and +ease of use as well (this time that is not contradictionary). + +BSD-Style blocks +---------------- +BSD style blocks are no longer supported (for good reason). See the +`rsyslog BSD blocks info page <http://www.rsyslog.com/g/BSD>`_ +for more information and how to upgrade your config. + +CEE-Properties +-------------- + +In rsyslog v6, CEE properties could not be used across disk-based queues. If this was +done, their content was reset. This was a missing feature in v6. In v7, this feature +has been implemented. Consequently, situations where the previous behaviour were +desired need now to be solved differently. We do not think that this will cause any +problems to anyone, especially as in v6 this was announced as a missing feature. + +omusrmsg: using just a username or "*" is deprecated +---------------------------------------------------- +In legacy config format, the asterisk denotes writing the message to all users. +This is usually used for emergency messages and configured like this: + +:: + + *.emerg * + +Unfortunately, the use of this single character conflicts with other uses, for +example with the multiplication operator. While rsyslog up to versions v7.4 preserves the meaning of +asterisk as an action, it is deprecated and will probably be removed in future versions. +Consequently, a warning message is emitted. To make this warning go away, the action must +be explicitly given, as follows: + +:: + + *.emerg :omusrmsg:* + +The same holds true for user names. For example + +:: + + *.emerg john + +at a minimum should be rewritten as + +:: + + *.emerg :omusrmsg:john + +Of course, for even more clarity the new RainerScript style of action can +also be used: + +:: + + *.emerg action(type="omusrmsg" users="john") + +In Rainer's blog, there is more +`background information on why omusrmsg needed to be changed <https://rainer.gerhards.net/2011/07/why-omusrmsg-is-evil-and-how-it-is.html>`_ +available. + +omruleset and discard (~) action are deprecated +----------------------------------------------- +Both continue to work, but have been replaced by better alternatives. + +The discard action (tilde character) has been replaced by the "stop" +RainerScript directive. It is considered more intuitive and offers slightly +better performance. + +The omruleset module has been replaced by the "call" RainerScript directive. +Call permits to execute a ruleset like a subroutine, and does so with much +higher performance than omruleset did. Note that omruleset could be run off +an async queue. This was more a side than a desired effect and is not supported +by the call statement. If that effect was needed, it can simply be simulated by +running the called rulesets actions asynchronously (what in any case is the right +way to handle this). + +Note that the deprecated modules emit warning messages when being used. +They tell that the construct is deprecated and which statement is to be used +as replacement. This does **not** affect operations: both modules are still +fully operational and will not be removed in the v7 timeframe. + +Retries of output plugins that do not do proper replies +------------------------------------------------------- +Some output plugins may not be able to detect if their target is capable of +accepting data again after an error (technically, they always return OK when +TryResume is called). Previously, the rsyslog core engine suspended such an action +after 1000 successive failures. This lead to potentially a large amount of +errors and error messages. Starting with 7.2.1, this has been reduced to 10 +successive failures. This still gives the plugin a chance to recover. In extreme +cases, a plugin may now enter suspend mode where it previously did not do so. +In practice, we do NOT expect that. + +omfile: file creation time +-------------------------- +Originally, omfile created files immediately during startup, no matter if +they were written to or not. In v7, this has changed. Files are only created +when they are needed for the first time. + +Also, in pre-v7 files were created *before* privileges were dropped. This meant +that files could be written to locations where the actual desired rsyslog +user was *not* permitted to. In v7, this has been fixed. This is fix also +the prime reason that files are now created on demand (which is later in the +process and after the privilege drop). + +Notes for the 7.3/7.4 branch +---------------------------- + +"last message repeated n times" Processing +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +This processing has been optimized and moved to the input side. This results +in usually far better performance and also de-couples different sources +from the same +processing. It is now also integrated in to the more generic rate-limiting +processing. + +User-Noticable Changes +...................... +The code works almost as before, with two exceptions: + +* The suppression amount can be different, as the new algorithm + precisely check's a single source, and while that source is being + read. The previous algorithm worked on a set of mixed messages + from multiple sources. +* The previous algorithm wrote a "last message repeated n times" message + at least every 60 seconds. For performance reasons, we do no longer do + this but write this message only when a new message arrives or rsyslog + is shut down. + +Note that the new algorithms needs support from input modules. If old +modules which do not have the necessary support are used, duplicate +messages will most probably not be detected. Upgrading the module code is +simple, and all rsyslog-provided plugins support the new method, so this +should not be a real problem (crafting a solution would result in rather +complex code - for a case that most probably would never happen). + +Performance Implications +........................ +In general, the new method enables far faster output processing. However, it +needs to be noted that the "last message repeated n" processing needs parsed +messages in order to detect duplicated. Consequently, if it is enabled the +parser step cannot be deferred to the main queue processing thread and +thus must be done during input processing. The changes workload distribution +and may have (good or bad) effect on the overall performance. If you have +a very high performance installation, it is suggested to check the performance +profile before deploying the new version. + +**Note:** for high-performance +environments it is highly recommended NOT to use "last message repeated n times" +processing but rather the other (more efficient) rate-limiting methods. These +also do NOT require the parsing step to be done during input processing. + +Stricter string-template Processing +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ +Previously, no error message for invalid string template parameters +was generated. +Rather a malformed template was generated, and error information emitted +at runtime. However, this could be quite confusing. Note that the new code +changes user experience: formerly, rsyslog and the affected +actions properly started up, but the actions did not produce proper +data. Now, there are startup error messages and the actions are NOT +executed (due to missing template due to template error). diff --git a/source/compatibility/v8compatibility.rst b/source/compatibility/v8compatibility.rst new file mode 100644 index 0000000..e2abc31 --- /dev/null +++ b/source/compatibility/v8compatibility.rst @@ -0,0 +1,200 @@ +Compatibility Notes for rsyslog v8 +================================== + +This document describes things to keep in mind when moving from v7 to +v8. It does not list enhancements nor does it talk about compatibility +concerns introduced by earlier versions (for this, see their respective +compatibility documents). Its focus is primarily on what you need to +know if you used v7 and want to use v8 without hassle. + +Version 8 offers a completely rewritten core rsyslog engine. This +resulted in a number of changes that are visible to users and (plugin) +developers. Most importantly, pre-v8 plugins **do not longer work** and +need to be updated to support the new calling interfaces. If you +developed a plugin, be sure to review the developer section below. + +Mark Messages +------------- + +In previous versions, mark messages were by default only processed if an +action was not executed for some time. The default has now changed, and +mark messages are now always processed. Note that this enables faster +processing inside rsyslog. To change to previous behaviour, you need to +add action.writeAllMarkMessages="off" to the actions in question. + +Untested Modules +---------------- + +The following modules have been updated and successfully build, but no +"real" test were conducted. Users of these modules should use extra +care. + +- mmsequence +- plugins/omgssapi +- omsnmp +- mmfields +- mmpstrucdata +- plugins/mmaudit +- ommongodb - larger changes still outstanding +- ompgsql +- plugins/omrabbitmq - not project supported +- plugins/omzmq3 - not project supported +- plugins/omhdfs (transaction support should be improved, requires sponsor) +- omuxsock + +In addition to bug reports, success reports are also appreciated for +these modules (this may save us testing). + +What Developers need to Know +---------------------------- + +output plugin interface +~~~~~~~~~~~~~~~~~~~~~~~ + +To support the new core engine, the output interface has been +considerably changed. It is suggested to review some of the +project-provided plugins for full details. In this doc, we describe the +most important changes from a high level perspective. + +**Multi-thread awareness required** + +The new engine activates one **worker**\ instance of output actions on +each worker thread. This means an action has now three types of data: + +- global +- action-instance - previously known pData, one for each action inside + the config +- worker-action-instance - one for each worker thread (called + pWrkrData), note that this is specific to exactly one pData + +The plugin **must** now by multi-threading aware. It may be called by +multiple threads concurrently, but it is guaranteed that each call is +for a unique pWrkrData structure. This still permits to write plugins +easily, but enables the engine to work with much higher performance. +Note that plugin developers should assume it is the norm that multiple +concurrent worker action instances are active a the some time. + +**New required entry points** + +In order to support the new threading model, new entry points are +required. Most importantly, only the plugin knows which data must be +present in pData and pWrkrData, so it must created and destroy these +data structures on request of the engine. Note that pWrkrData may be +destroyed at any time and new ones re-created later. Depending on +workload structure and configuration, this can happen frequently. + +New entry points are: + +- createWrkrInstance +- freeWrkrInstance + +The calling interface for these entry points has changed. Basically, +they now receive a pWrkrData object instead pData. It is assumed that +createWrkrInstance populates pWrkrData->pData appropriately. + +- beginTransaction +- doAction +- endTransaction + +**Changed entry points** + +Some of the existing entry points have been changed. + +The **doAction** entry point formerly got a variable ``iMsgOpts`` which +is no longer provided. This variable was introduced in early days and +exposed some internal message state information to the output module. +Review of all known existing plugins showed that none except omfile ever +used that variable. And omfile only did so to do some no longer required +legacy handling. + +In essence, it is highly unlikely that you ever accessed this variable. +So we expect that nobody actually notices that the variable has gone +away. + +Removal of the variable provides a slight performance gain, as we do no +longer need to maintain it inside the output system (which leads to less +CPU instructions and better cache hits). + +**RS\_RET\_SUSPENDED is no longer supported when creating an action +instance** + +This means a plugin must not try to establish any connections or the +like before any of its processing entry points (like beginTransaction or +doAction) is called. This was generally also the case with v7, but was +not enforced in all cases. In v8, creating action fails if +anything but RS\_RET\_OK is returned. + +string generator interface +~~~~~~~~~~~~~~~~~~~~~~~~~~ + +Bottom line: string generators need to be changed or will abort. + +The BEGINstrgen() entry point has greatly changed. Instead of two +parameters for the output buffers, they now receive a single ``iparam`` +pointer, which contains all data items needed. Also, the message pointer +is now const to "prevent" (accidental) changes to the message via the +strgen interface. + +Note that strgen modules must now maintain the iparam->lenStr field, +which must hold the length of the generated string on exit. This is +necessary as we cache the string sizes in order to reduced strlen() +calls. Also, the numerical parameters are now unsigned and no longer +size\_t. This permits us to store them directly into optimized heap +structures. + +Specifics for Version 8.3 and 8.4 +--------------------------------- + +Unsupported Command Line Options Removed +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +The command line options a, h, m, o, p, g, r, t and c were not +supported since many versions. However, they spit out an error +message that they were unsupported. This error message now no +longer appears, instead the regular usage() display happens. +This should not have any effect to users. + + +Specifics for Version 8.5 and 8.6 +--------------------------------- + +imfile changes +~~~~~~~~~~~~~~ + +Starting with 8.5.0, imfile supports wildcards in file names, but +does do so only in inotify mode. In order to support wildcards, the +handling of statefile needed to be changed. Most importantly, the +*statefile* input parameter has been deprecated. See +:doc:`imfile module documentation <../../configuration/modules/imfile>` +for more details. + +Command Line Options +~~~~~~~~~~~~~~~~~~~~ +There is a small set of configuration command line options available dating back +to the dark ages of syslog technology. Setting command-line options is +distro specific and a hassle for most users. As such, we are phasing out +these options, and will do so rather quickly. + +Some of them (most notably -l, -s) will completely be removed, as +feedback so far indicated they are no longer in use. Others will be +replaced by proper configuration objects. + +**Expect future rsyslog versions to no longer accept those configuration +command line options.** + +Please see this table to see what to use as a replacement for the +current options: + +========== =========================================================================== +**Option** **replacement** +-4 global(net.ipprotocol="ipv4-only") +-6 global(net.ipprotocol="ipv6-only") +-A omfwd input parameter "udp.sendToAll" +-l dropped, currently no replacement +-q global(net.aclAddHostnameOnFail="on") +-Q global(net.aclResolveHostname="off") +-s dropped, currently no replacement +-S omrelp action parameter "localclientip" +-w global(net.permitACLWarning="off") +-x global(net.enableDNS="off") +========== =========================================================================== + diff --git a/source/concepts/index.rst b/source/concepts/index.rst new file mode 100644 index 0000000..2119e40 --- /dev/null +++ b/source/concepts/index.rst @@ -0,0 +1,16 @@ +Concepts +======== + +This chapter describes important rsyslog concepts and objects. Where +appropriate, it also refers to configurations settings to affect +the respective objects. + +.. toctree:: + :maxdepth: 2 + + queues + janitor + messageparser + multi_ruleset + netstrm_drvr + diff --git a/source/concepts/janitor.rst b/source/concepts/janitor.rst new file mode 100644 index 0000000..52765ed --- /dev/null +++ b/source/concepts/janitor.rst @@ -0,0 +1,41 @@ +The Janitor Process +=================== +The janitor process carries out periodic cleanup tasks. For example, +it is used by +:doc:`omfile <../configuration/modules/omfile>` +to close files after a timeout has expired. + +The janitor runs periodically. As such, all tasks carried out via the +janitor will be activated based on the interval at which it runs. This +means that all janitor-related times set are approximate and should be +considered as "no earlier than" (NET). If, for example, you set a timeout +to 5 minutes and the janitor is run in 10-minute intervals, the timeout +may actually happen after 5 minutes, but it may also take up to 20 +minutes for it to be detected. + +In general (see note about HUP below), janitor based activities scheduled +to occur after *n* minutes will occur after *n* and *(n + 2\*janitorInterval)* +minutes. + +To reduce the potential delay caused by janitor invocation, +:ref:`the interval at which the janitor runs can be be adjusted <global_janitorInterval>`\ . +If high precision is +required, it should be set to one minute. Janitor-based activities will +still be NET times, but the time frame will be much smaller. In the +example with the file timeout, it would be between 5 and 6 minutes if the +janitor is run at a one-minute interval. + +Note that the more frequent the janitor is run, the more frequent the +system needs to wakeup from potential low power state. This is no issue +for data center machines (which usually always run at full speed), but it +may be an issue for power-constrained environments like notebooks. For +such systems, a higher janitor interval may make sense. + +As a special case, sending a HUP signal to rsyslog also activate the +janitor process. This can lead to too-frequent wakeups of janitor-related +services. However, we don't expect this to cause any issues. If it does, +it could be solved by creating a separate thread for the janitor. But as +this takes up some system resources and is not not considered useful, we +have not implemented it that way. If the HUP/janitor interaction causes +problems, let the rsyslog team know and we can change the implementation. + diff --git a/source/concepts/messageparser.rst b/source/concepts/messageparser.rst new file mode 100644 index 0000000..f9886be --- /dev/null +++ b/source/concepts/messageparser.rst @@ -0,0 +1,304 @@ +Message parsers in rsyslog +========================== + +Written by `Rainer Gerhards <http://www.gerhards.net/rainer>`_ +(2009-11-06) + +Intro +----- + +Message parsers are a feature of rsyslog 5.3.4 and above. In this +article, I describe what message parsers are, what they can do and how +they relate to the relevant standards. I will also describe what you can +not do with time. Finally, I give some advice on implementing your own +custom parser. + +What are message parsers? +------------------------- + +Well, the quick answer is that message parsers are the component of +rsyslog that parses the syslog message after it is being received. Prior +to rsyslog 5.3.4, message parsers where built in into the rsyslog core +itself and could not be modified (other than by modifying the rsyslog +code). + +In 5.3.4, we changed that: message parsers are now loadable modules +(just like input and output modules). That means that new message +parsers can be added without modifying the rsyslog core, even without +contributing something back to the project. + +But that doesn't answer what a message parser really is. What does it +mean to "parse a message" and, maybe more importantly, what is a +message? To answer these questions correctly, we need to dig down into +the relevant standards. `RFC5424 <http://tools.ietf.org/html/rfc5424>`_ +specifies a layered architecture for the syslog protocol: + +.. figure:: rfc5424layers.png + :align: center + :alt: RFC5424 syslog protocol layers + + RFC5424 syslog protocol layers + +For us important is the distinction between the syslog transport and the +upper layers. The transport layer specifies how a stream of messages is +assembled at the sender side and how this stream of messages is +disassembled into the individual messages at the receiver side. In +networking terminology, this is called "framing". The core idea is that +each message is put into a so-called "frame", which then is transmitted +over the communications link. + +The framing used is depending on the protocol. For example, in UDP the +"frame"-equivalent is a packet that is being sent (this also means that +no two messages can travel within a single UDP packet). In "plain tcp +syslog", the industry standard, LF is used as a frame delimiter (which +also means that no multi-line message can properly be transmitted, a +"design" flaw in plain tcp syslog). In +`RFC5425 <http://tools.ietf.org/html/rfc5425>`_ there is a header in +front of each frame that contains the size of the message. With this +framing, any message content can properly be transferred. + +And now comes the important part: **message parsers do NOT operate at +the transport layer**, they operate, as their name implies, on messages. +So we can not use message parsers to change the underlying framing. For +example, if a sender splits (for whatever reason) a single message into +two and encapsulates these into two frames, there is no way a message +parser could undo that. + +A typical example may be a multi-line message: let's assume some +originator has generated a message for the format "A\\nB" (where \\n +means LF). If that message is being transmitted via plain tcp syslog, +the frame delimiter is LF. So the sender will delimit the frame with LF, +but otherwise send the message unmodified onto the wire (because that is +how things are -unfortunately- done in plain tcp syslog...). So wire +will see "A\\nB\\n". When this arrives at the receiver, the transport +layer will undo the framing. When it sees the LF after A, it thinks it +finds a valid frame delimiter (in fact, this is the correct view!). So +the receive will extract one complete message A and one complete message +B, not knowing that they once were both part of a large multi-line +message. These two messages are then passed to the upper layers, where +the message parsers receive them and extract information. However, the +message parsers never know (or even have a chance to see) that A and B +belonged together. Even further, in rsyslog there is no guarantee that A +will be parsed before B - concurrent operations may cause the reverse +order (and do so very validly). + +The important lesson is: **message parsers can not be used to fix a +broken framing**. You need a full protocol implementation to do that, +what is the domain of input and output modules. + +I have now told you what you can not do with message parsers. But what +they are good for? Thankfully, broken framing is not the primary problem +of the syslog world. A wealth of different formats is. Unfortunately, +many real-world implementations violate the relevant standards in one +way or another. That makes it often very hard to extract meaningful +information from a message or to process messages from different sources +by the same rules. In my article `syslog parsing in +rsyslog <syslog_parsing.html>`_ I have elaborated on all the real-world +evil that you can usually see. So I won't repeat that here. But in +short, the real problem is not the framing, but how to make malformed +messages well-looking. + +**This is what message parsers permit you to do: take a (well-known) +malformed message, parse it according to its semantics and generate +perfectly valid internal message representations from it.** So as long +as messages are consistently in the same wrong format (and they usually +are!), a message parser can look at that format, parse it, and make the +message processable just like it were well formed in the first place. +Plus, one can abuse the interface to do some other "interesting" tricks, +but that would take us to far. + +While this functionality may not sound exciting, it actually solves a +very big issue (that you only really understand if you have managed a +system with various different syslog sources). Note that we were often +able to process malformed messages in the past with the help of the +property replacer and regular expressions. While this is nice, it has a +performance hit. A message parser is a C code, compiled to native +language, and thus typically much faster than any regular expression +based method (depending, of course, on the quality of the +implementation...). + +How are message parsers used? +----------------------------- + +In a simplified view, rsyslog + +#. first receives messages (via the input module), +#. *then parses them (at the message level!)* and +#. then processes them (operating on the internal message + representation). + +Message parsers are utilized in the second step (written in italics). +Thus, they take the raw message (NOT frame!) received from the remote +system and create the internal structure out of it that the other parts +of rsyslog need in order to perform their processing. Parsing is vital, +because an unparsed message can not be processed in the third stage, the +actual application-level processing (like forwarding or writing to +files). + +Parser Chains and how they Operate +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +Rsyslog chains parsers together to provide flexibility. A **parser +chain** contains all parsers that can potentially be used to parse a +message. It is assumed that there is some way a parser can detect if the +message it is being presented is supported by it. If so, the parser will +tell the rsyslog engine and parse the message. The rsyslog engine now +calls each parser inside the chain (in sequence!) until the first parser +is able to parse the message. After one parser has been found, the +message is considered parsed and no others parsers are called on that +message. + +Side-note: this method implies there are some "not-so-dirty" tricks +available to modify the message by a parser module that declares itself +as "unable to parse" but still does some message modification. This was +not a primary design goal, but may be utilized, and the interface +probably extended, to support generic filter modules. These would need +to go to the root of the parser chain. As mentioned, the current system +already supports this. + +The position inside the parser chain can be thought of as a priority: +parser sitting earlier in the chain take precedence over those sitting +later in it. So more specific parser should go earlier in the chain. A +good example of how this works is the default parser set provided by +rsyslog: rsyslog.rfc5424 and rsyslog.rfc3164, each one parses according +to the rfc that has named it. RFC5424 was designed to be distinguishable +from RFC3164 message by the sequence "1 " immediately after the +so-called PRI-part (don't worry about these words, it is sufficient if +you understand there is a well-defined sequence used to identify RFC5424 +messages). In contrary, RFC3164 actually permits everything as a valid +message. Thus the RFC3164 parser will always parse a message, sometimes +with quite unexpected outcome (there is a lot of guesswork involved in +that parser, which unfortunately is unavoidable due to existing +technology limits). So the default parser chain is to try the RFC5424 +parser first and after it the RFC3164 parser. If we have a +5424-formatted message, that parser will identify and parse it and the +rsyslog engine will stop processing. But if we receive a legacy syslog +message, the RFC5424 will detect that it can not parse it, return this +status to the engine which then calls the next parser inside the chain. +That usually happens to be the RFC3164 parser, which will always process +the message. But there could also be any other parser inside the chain, +and then each one would be called unless one that is able to parse can +be found. + +If we reversed the parser order, RFC5424 messages would incorrectly +parsed. Why? Because the RFC3164 parser will always parse every message, +so if it were asked first, it would parse (and misinterpret) the +5424-formatted message, return it did so and the rsyslog engine would +never call the 5424 parser. So order of sequence is very important. + +What happens if no parser in the chain could parse a message? Well, then +we could not obtain the in-memory representation that is needed to +further process the message. In that case, rsyslog has no other choice +than to discard the message. If it does so, it will emit a warning +message, but only in the first 1,000 incidents. This limit is a safety +measure against message-loops, which otherwise could quickly result from +a parser chain misconfiguration. **If you do not tolerate loss of +unparsable messages, you must ensure that each message can be parsed.** +You can easily achieve this by always using the "rsyslog-rfc3164" parser +as the *last* parser inside parser chains. That may result in invalid +parsing, but you will have a chance to see the invalid message (in debug +mode, a warning message will be written to the debug log each time a +message is dropped due to inability to parse it). + +Where are parser chains used? +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +We now know what parser chains are and how they operate. The question is +now how many parser chains can be active and how it is decided which +parser chain is used on which message. This is controlled via +:doc:`rsyslog's rulesets <multi_ruleset>`. In short, multiple rulesets can be +defined and there always exist at least one ruleset. +A parser chain is bound to a +specific ruleset. This is done by virtue of defining parsers via the +:doc:`$RulesetParser <../configuration/ruleset/rsconf1_rulesetparser>` +configuration directive +(for specifics, see there). If no such directive is specified, the +default parser chain is used. As of this writing, the default parser +chain always consists of "rsyslog.rfc5424", "rsyslog.rfc3164", in that +order. As soon as a parser is configured, the default list is cleared +and the new parser is added to the end of the (initially empty) +ruleset's parser chain. + +The important point to know is that parser chains are defined on a +per-ruleset basis. + +Can I use different parser chains for different devices? +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +The correct answer is: generally yes, but it depends. First of all, +remember that input modules (and specific listeners) may be bound to +specific rulesets. As parser chains "reside" in rulesets, binding to a +ruleset also binds to the parser chain that is bound to that ruleset. As +a number one prerequisite, the input module must support binding to +different rulesets. Not all do, but their number is growing. For +example, the important `imudp <imudp.html>`_ and `imtcp <imtcp.html>`_ +input modules support that functionality. Those that do not (for example +`im3195 <im3195>`_) can only utilize the default ruleset and thus the +parser chain defined in that ruleset. + +If you do not know if the input module in question supports ruleset +binding, check its documentation page. Those that support it have the +required directives. + +Note that it is currently under evaluation if rsyslog will support +binding parser chains to specific inputs directly, without depending on +the ruleset. There are some concerns that this may not be necessary but +adds considerable complexity to the configuration. So this may or may +not be possible in the future. In any case, if we decide to add it, +input modules need to support it, so this functionality would require +some time to implement. + +The cookbook recipe for using different parsers for different devices +is given as an actual in-depth example in the +`$RulesetParser` configuration directive +doc page. In short, it is accomplished by defining specific rulesets for +the required parser chains, defining different listener ports for each +of the devices with different format and binding these listeners to the +correct ruleset (and thus parser chains). Using that approach, a variety +of different message formats can be supported via a single rsyslog +instance. + +Which message parsers are available +----------------------------------- + +As of this writing, there exist only two message parsers, one for +RFC5424 format and one for legacy syslog (loosely described in +`RFC3164 <http://tools.ietf.org/html/rfc3164>`_). These parsers are +built-in and must not be explicitly loaded. However, message parsers can +be added with relative ease by anyone knowing to code in C. Then, they +can be loaded via $ModLoad just like any other loadable module. It is +expected that the rsyslog project will be contributed additional message +parsers over time, so that at some point there hopefully is a rich +choice of them (I intend to add a browsable repository as soon as new +parsers pop up). + +How to write a message parser? +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +As a prerequisite, you need to know the exact format that the device is +sending. Then, you need moderate C coding skills, and a little bit of +rsyslog internals. I guess the rsyslog specific part should not be that +hard, as almost all information can be gained from the existing parsers. +They are rather simple in structure and can be found under the "./tools" +directory. They are named pmrfc3164.c and pmrfc5424.c. You need to +follow the usual loadable module guidelines. It is my expectation that +writing a parser should typically not take longer than a single day, +with maybe a day more to get acquainted with rsyslog. Of course, I am +not sure if the number is actually right. + +If you can not program or have no time to do it, Adiscon can also write +a message parser for you as part of the `rsyslog professional services +offering <http://www.rsyslog.com/professional-services>`_. + +Conclusion +---------- + +Malformed syslog messages are a pain and unfortunately often seen in +practice. Message parsers provide a fast and efficient solution for this +problem. Different parsers can be defined for different devices, and +they all convert message information into rsyslog's well-defined +internal format. Message parsers were first introduced in rsyslog 5.3.4 +and also offer some interesting ideas that may be explored in the future +- up to full message normalization capabilities. It is strongly +recommended that anyone with a heterogeneous environment take a look at +message parser capabilities. diff --git a/source/concepts/multi_ruleset.rst b/source/concepts/multi_ruleset.rst new file mode 100644 index 0000000..512558e --- /dev/null +++ b/source/concepts/multi_ruleset.rst @@ -0,0 +1,320 @@ +Multiple Rulesets in rsyslog +============================ + +Starting with version 4.5.0 and 5.1.1, +`rsyslog <http://www.rsyslog.com>`_ supports multiple rulesets within a +single configuration. This is especially useful for routing the +reception of remote messages to a set of specific rules. Note that the +input module must support binding to non-standard rulesets, so the +functionality may not be available with all inputs. + +In this document, I am using :doc:`imtcp <../configuration/modules/imtcp>`, an input module that +supports binding to non-standard rulesets since rsyslog started to +support them. + +What is a Ruleset? +------------------ + +If you have worked with (r)syslog.conf, you know that it is made up of +what I call rules (others tend to call them selectors, a sysklogd term). +Each rule consist of a filter and one or more actions to be carried out +when the filter evaluates to true. A filter may be as simple as a +traditional syslog priority based filter (like "\*.\*" or "mail.info" or +a as complex as a script-like expression. Details on that are covered in +the config file documentation. After the filter come action specifiers, +and an action is something that does something to a message, e.g. write +it to a file or forward it to a remote logging server. + +A traditional configuration file is made up of one or more of these +rules. When a new message arrives, its processing starts with the first +rule (in order of appearance in rsyslog.conf) and continues for each +rule until either all rules have been processed or a so-called "discard" +action happens, in which case processing stops and the message is thrown +away (what also happens after the last rule has been processed). + +The **multi-ruleset** support now permits to specify more than one such +rule sequence. You can think of a traditional config file just as a +single default rule set, which is automatically bound to each of the +inputs. This is even what actually happens. When rsyslog.conf is +processed, the config file parser looks for the directive + +:: + + ruleset(name="rulesetname") + +Where name is any name the user likes (but must not start with +"RSYSLOG\_", which is the name space reserved for rsyslog use). If it +finds this directive, it begins a new rule set (if the name was not yet +know) or switches to an already-existing one (if the name was known). +All rules defined between this $RuleSet directive and the next one are +appended to the named ruleset. Note that the reserved name +"RSYSLOG\_DefaultRuleset" is used to specify rsyslogd's default ruleset. +You can use that name wherever you can use a ruleset name, including +when binding an input to it. + +Inside a ruleset, messages are processed as described above: they start +with the first rule and rules are processed in the order of appearance +of the configuration file until either there are no more rules or the +discard action is executed. Note that with multiple rulesets no longer +**all** rsyslog.conf rules are executed but **only** those that are +contained within the specific ruleset. + +Inputs must explicitly bind to rulesets. If they don't, the default +ruleset is bound. + +This brings up the next question: + +What does "To bind to a Ruleset" mean? +-------------------------------------- + +This term is used in the same sense as "to bind an IP address to an +interface": it means that a specific input, or part of an input (like a +tcp listener) will use a specific ruleset to "pass its messages to". So +when a new message arrives, it will be processed via the bound ruleset. +Rules from all other rulesets are irrelevant and will never be processed. + +This makes multiple rulesets very handy to process local and remote +message via separate means: bind the respective receivers to different +rule sets, and you do not need to separate the messages by any other +method. + +Binding to rulesets is input-specific. For imtcp, this is done via the + +:: + + input(type="imptcp" port="514" ruleset="rulesetname") + +directive. Note that "rulesetname" must be the name of a ruleset that is +already defined at the time the bind directive is given. There are many +ways to make sure this happens, but I personally think that it is best +to define all rule sets at the top of rsyslog.conf and define the inputs +at the bottom. This kind of reverses the traditional recommended +ordering, but seems to be a really useful and straightforward way of +doing things. + +Why are rulesets important for different parser configurations? +--------------------------------------------------------------- + +Custom message parsers, used to handle different (and potentially +otherwise-invalid) message formats, can be bound to rulesets. So +multiple rulesets can be a very useful way to handle devices sending +messages in different malformed formats in a consistent way. +Unfortunately, this is not uncommon in the syslog world. An in-depth +explanation with configuration sample can be found at the +:doc:`$RulesetParser <../configuration/ruleset/rsconf1_rulesetparser>` configuration directive. + +Can I use a different Ruleset as the default? +--------------------------------------------- + +This is possible by using the + +:: + + $DefaultRuleset <name> + +Directive. Please note, however, that this directive is actually global: +that is, it does not modify the ruleset to which the next input is bound +but rather provides a system-wide default rule set for those inputs that +did not explicitly bind to one. As such, the directive can not be used +as a work-around to bind inputs to non-default rulesets that do not +support ruleset binding. + +Rulesets and Queues +------------------- + +By default, rulesets do not have their own queue. It must be activated +via the $RulesetCreateMainQueue directive, or if using rainerscript +format, by specifying queue parameters on the ruleset directive, e.g. + +:: + + ruleset(name="whatever" queue.type="fixedArray" queue. ...) + +See :doc:`http://www.rsyslog.com/doc/master/rainerscript/queue\_parameters.html <../rainerscript/queue_parameters>` +for more details. + +Please note that when a ruleset uses its own queue, processing of the ruleset +happens **asynchronously** to the rest of processing. As such, any modifications +made to the message object (e.g. message or local variables that are set) or +discarding of the message object **have no effect outside that ruleset**. So +if you want to modify the message object inside the ruleset, you **cannot** +define a queue for it. Most importantly, you cannot call it and expect the +modified properties to be present when the call returns. Even more so, the +call will most probably return before the message is even begun to be processed +by the ruleset in question. + +Note that in RainerScript format specifying any "queue.\*" can cause the +creation of a dedicated queue and as such asynchronous processing. This is +because queue parameters cannot be specified without a queue. Note, though, +that the actual creation is **guaranteed** only if "queue.type" is specified +as above. So if you intentionally want to assign a separate queue to the +ruleset, do so as shown above. + +Examples +-------- + +Split local and remote logging +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +Let's say you have a pretty standard system that logs its local messages +to the usual bunch of files that are specified in the default +rsyslog.conf. As an example, your rsyslog.conf might look like this: + +:: + + # ... module loading ... + # The authpriv file has restricted access. + authpriv.* /var/log/secure + # Log all the mail messages in one place. + mail.* /var/log/maillog + # Log cron stuff + cron.* /var/log/cron + # Everybody gets emergency messages + *.emerg * + ... more ... + +Now, you want to add receive messages from a remote system and log these +to a special file, but you do not want to have these messages written to +the files specified above. The traditional approach is to add a rule in +front of all others that filters on the message, processes it and then +discards it: + +:: + + # ... module loading ... + # process remote messages + if $fromhost-ip == '192.0.2.1' then { + action(type="omfile" file="/var/log/remotefile02") + stop + } + + + # only messages not from 192.0.2.1 make it past this point + + # The authpriv file has restricted access. + authpriv.* /var/log/secure + # Log all the mail messages in one place. + mail.* /var/log/maillog + # Log cron stuff + cron.* /var/log/cron + # Everybody gets emergency messages + *.emerg * + ... more ... + +Note that "stop" is the discard action!. Also note that we assume that +192.0.2.1 is the sole remote sender (to keep it simple). + +With multiple rulesets, we can simply define a dedicated ruleset for the +remote reception case and bind it to the receiver. This may be written +as follows: + +:: + + # ... module loading ... + # process remote messages + # define new ruleset and add rules to it: + ruleset(name="remote"){ + action(type="omfile" file="/var/log/remotefile") + } + # only messages not from 192.0.2.1 make it past this point + + # bind ruleset to tcp listener and activate it: + input(type="imptcp" port="10514" ruleset="remote") + +Split local and remote logging for three different ports +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +This example is almost like the first one, but it extends it a little +bit. While it is very similar, I hope it is different enough to provide +a useful example why you may want to have more than two rulesets. + +Again, we would like to use the "regular" log files for local logging, +only. But this time we set up three syslog/tcp listeners, each one +listening to a different port (in this example 10514, 10515, and 10516). +Logs received from these receivers shall go into different files. Also, +logs received from 10516 (and only from that port!) with "mail.\*" +priority, shall be written into a specific file and **not** be written to +10516's general log file. + +This is the config: + +:: + + # ... module loading ... + # process remote messages + + ruleset(name="remote10514"){ + action(type="omfile" file="/var/log/remote10514") + } + + ruleset(name="remote10515"){ + action(type="omfile" file="/var/log/remote10515") + } + + ruleset(name="remote10516"){ + if prifilt("mail.*") then { + /var/log/mail10516 + stop + # note that the stop-command will prevent this message from + # being written to the remote10516 file - as usual... + } + /var/log/remote10516 + } + + + # and now define listeners bound to the relevant ruleset + input(type="imptcp" port="10514" ruleset="remote10514") + input(type="imptcp" port="10515" ruleset="remote10515") + input(type="imptcp" port="10516" ruleset="remote10516") + +Performance +----------- + +Fewer Filters +~~~~~~~~~~~~~ + +No rule processing can be faster than not processing a rule at all. As +such, it is useful for a high performance system to identify disjunct +actions and try to split these off to different rule sets. In the +example section, we had a case where three different tcp listeners need +to write to three different files. This is a perfect example of where +multiple rule sets are easier to use and offer more performance. The +performance is better simply because there is no need to check the +reception service - instead messages are automatically pushed to the +right rule set and can be processed by very simple rules (maybe even +with "\*.\*"-filters, the fastest ones available). + +Partitioning of Input Data +~~~~~~~~~~~~~~~~~~~~~~~~~~ + +Starting with rsyslog 5.3.4, rulesets permit higher concurrency. They +offer the ability to run on their own "main" queue. What that means is +that a own queue is associated with a specific rule set. That means that +inputs bound to that ruleset do no longer need to compete with each +other when they enqueue a data element into the queue. Instead, enqueue +operations can be completed in parallel. + +An example: let us assume we have three TCP listeners. Without rulesets, +each of them needs to insert messages into the main message queue. So if +each of them wants to submit a newly arrived message into the queue at +the same time, only one can do so while the others need to wait. With +multiple rulesets, its own queue can be created for each ruleset. If now +each listener is bound to its own ruleset, concurrent message submission +is possible. On a machine with a sufficiently large number of cores, +this can result in dramatic performance improvement. + +It is highly advised that high-performance systems define a dedicated +ruleset, with a dedicated queue for each of the inputs. + +By default, rulesets do **not** have their own queue. It must be +activated via the +:doc:`$RulesetCreateMainQueue <../configuration/ruleset/rsconf1_rulesetcreatemainqueue>` +directive. + +See Also +-------- +.. toctree:: + :maxdepth: 1 + + ../historical/multi_ruleset_legacy_format_samples + diff --git a/source/concepts/netstrm_drvr.rst b/source/concepts/netstrm_drvr.rst new file mode 100644 index 0000000..182fcdf --- /dev/null +++ b/source/concepts/netstrm_drvr.rst @@ -0,0 +1,21 @@ +NetStream Drivers +================= + +Network stream drivers are a layer between various parts of rsyslogd +(e.g. the imtcp module) and the transport layer. They provide sequenced +delivery, authentication and confidentiality to the upper layers. +Drivers implement different capabilities. + +Users need to know about netstream drivers because they need to +configure the proper driver, and proper driver properties, to achieve +desired results (e.g. a :doc:`../tutorials/tls`). + +Current Network Stream Drivers +------------------------------ + +.. toctree:: + :maxdepth: 2 + + ns_ptcp + ns_gtls + ns_ossl diff --git a/source/concepts/ns_gtls.rst b/source/concepts/ns_gtls.rst new file mode 100644 index 0000000..17fe29c --- /dev/null +++ b/source/concepts/ns_gtls.rst @@ -0,0 +1,91 @@ +gtls Network Stream Driver +========================== + +This network stream driver implements a TLS +protected transport via the `GnuTLS +library <http://www.gnu.org/software/gnutls/>`_. + +**Available since:** 3.19.0 (suggested minimum 3.19.8 and above) + +Supported Driver Modes +====================== + +- **0** - unencrypted transmission (just like `ptcp <ns_ptcp.html>`_ driver) +- **1** - TLS-protected operation + +.. note:: + + Mode 0 does not provide any benefit over the ptcp driver. This + mode exists for technical reasons, but should not be used. It may be + removed in the future. + +Supported Authentication Modes +============================== + +- **anon** - anonymous authentication as described in IETF's + draft-ietf-syslog-transport-tls-12 Internet draft + +- **x509/fingerprint** - certificate fingerprint authentication as + described in IETF's draft-ietf-syslog-transport-tls-12 Internet draft. + The fingerprint must be provided as the SHA1 or the SHA256 hex string of + the certificate. Multiple values must be separated by comma (,). + A valid configuration would be e.G. + :: + + StreamDriverPermittedPeers="SHA256:10:C4:26:1D:CB:3C:AB:12:DB:1A:F0:47:37:AE:6D:D2:DE:66:B5:71:B7:2E:5B:BB:AE:0C:7E:7F:5F:0D:E9:64,SHA1:DD:23:E3:E7:70:F5:B4:13:44:16:78:A5:5A:8C:39:48:53:A6:DD:25" + +- **x509/certvalid** - certificate validation only + +- **x509/name** - certificate validation and subject name authentication as + described in IETF's draft-ietf-syslog-transport-tls-12 Internet draft + +.. note:: + + "anon" does not permit to authenticate the remote peer. As such, + this mode is vulnerable to man in the middle attacks as well as + unauthorized access. It is recommended NOT to use this mode. + A certificate/key does not need to be configured in this authmode. + +.. note:: + + **Anon mode changes in:** v8.190 (or above) + + - Anonymous Ciphers (DH and ECDH) are available in ANON mode. + Note: ECDH is not available on GnuTLS Version below 3.x. + - Server does not require a certificate anymore in anon mode. + - If Server has a certificate and the Client does not, the highest possible + ciphers will be selected. + - If both Server and Client do not have a certificate, the highest available + anon cipher will be used. + +x509/certvalid is a nonstandard mode. It validates the remote peers +certificate, but does not check the subject name. This is weak +authentication that may be useful in scenarios where multiple devices +are deployed and it is sufficient proof of authenticity when their +certificates are signed by the CA the server trusts. This is better than +anon authentication, but still not recommended. **Known Problems** + + +CheckExtendedKeyPurpose +======================= + +- **off** - by default this binary argument is turned off, which means + that Extended Key Usage extension of GNUTls certificates is ignored + in cert validation. + +- **on** - if you turn this option on, it will check that peer's certificate + contains the value for GNUTLS_KP_TLS_WWW_SERVER or GNUTLS_KP_TLS_WWW_CLIENT + respectively, depending whether we are on sending or receiving end of a + connection. + +PrioritizeSAN +============= + +- **off** - by default this binary argument is turned off, which means + that validation of names in certificates goes per older RFC 5280 and either + Subject Alternative Name or Common Name match is good and connection is + allowed. + +- **on** - if you turn this option on, it will perform stricter name checking + as per newer RFC 6125, where, if any SAN is found, contents of CN are + completely ignored and name validity is decided based on SAN only. diff --git a/source/concepts/ns_ossl.rst b/source/concepts/ns_ossl.rst new file mode 100644 index 0000000..cbd002e --- /dev/null +++ b/source/concepts/ns_ossl.rst @@ -0,0 +1,76 @@ +***************************** +openssl Network Stream Driver +***************************** + +=========================== =========================================================================== +**Driver Name:** **ossl** +**Author:** Andre Lorbach <alorbach@adiscon.com> +**Available since:** 8.36.0 +=========================== =========================================================================== + + +Purpose +======= + +This network stream driver implements a TLS protected transport +via the `OpenSSL library <https://www.openssl.org/>`_. + + +Supported Driver Modes +====================== + +- **0** - unencrypted transmission (just like `ptcp <ns_ptcp.html>`_ driver) +- **1** - TLS-protected operation + +.. note:: + + Mode 0 does not provide any benefit over the ptcp driver. This + mode exists for technical reasons, but should not be used. It may be + removed in the future. + + +Supported Authentication Modes +============================== + +- **anon** - anonymous authentication as described in IETF's + draft-ietf-syslog-transport-tls-12 Internet draft + +- **x509/fingerprint** - certificate fingerprint authentication as + described in IETF's draft-ietf-syslog-transport-tls-12 Internet draft. + The fingerprint must be provided as the SHA1 or the SHA256 hex string of + the certificate. Multiple values must be separated by comma (,). + A valid configuration would be e.G. + :: + + StreamDriverPermittedPeers="SHA256:10:C4:26:1D:CB:3C:AB:12:DB:1A:F0:47:37:AE:6D:D2:DE:66:B5:71:B7:2E:5B:BB:AE:0C:7E:7F:5F:0D:E9:64,SHA1:DD:23:E3:E7:70:F5:B4:13:44:16:78:A5:5A:8C:39:48:53:A6:DD:25" + +- **x509/certvalid** - certificate validation only. x509/certvalid is + a nonstandard mode. It validates the remote peers certificate, but + does not check the subject name. This is weak authentication that may + be useful in scenarios where multiple devices are deployed and it is + sufficient proof of authenticity when their certificates are signed by + the CA the server trusts. This is better than anon authentication, but + still not recommended. **Known Problems** + +- **x509/name** - certificate validation and subject name authentication as + described in IETF's draft-ietf-syslog-transport-tls-12 Internet draft + +.. note:: + + "anon" does not permit to authenticate the remote peer. As such, + this mode is vulnerable to man in the middle attacks as well as + unauthorized access. It is recommended NOT to use this mode. + A certificate / key does not need to be configured in this authmode. + +.. note:: + + **Anon mode changes in:** v8.190 (or above) + + - Anonymous Ciphers (DH and ECDH) are available in ANON mode. + - Server does not require a certificate anymore in anon mode. + - If Server has a certificate and the Client does not, the highest possible + ciphers will be selected. + - If both Server and Client do not have a certificate, the highest available + anon cipher will be used. + + diff --git a/source/concepts/ns_ptcp.rst b/source/concepts/ns_ptcp.rst new file mode 100644 index 0000000..66d7062 --- /dev/null +++ b/source/concepts/ns_ptcp.rst @@ -0,0 +1,13 @@ +ptcp Network Stream Driver +========================== + +This network stream driver implement a plain tcp +transport without security properties. + +Supported Driver Modes + +- 0 - unencrypted transmission + +Supported Authentication Modes + +- "anon" - no authentication diff --git a/source/concepts/queues.rst b/source/concepts/queues.rst new file mode 100644 index 0000000..bb5647c --- /dev/null +++ b/source/concepts/queues.rst @@ -0,0 +1,524 @@ +Understanding rsyslog Queues +============================ + +Rsyslog uses queues whenever two activities need to be loosely coupled. +With a queue, one part of the system "produces" something while another +part "consumes" this something. The "something" is most often syslog +messages, but queues may also be used for other purposes. + +This document provides a good insight into technical details, operation +modes and implications. In addition to it, an :doc:`rsyslog queue concepts +overview <../whitepapers/queues_analogy>` document exists which tries to explain +queues with the help of some analogies. This may probably be a better +place to start reading about queues. I assume that once you have +understood that document, the material here will be much easier to grasp +and look much more natural. + +The most prominent example is the main message queue. Whenever rsyslog +receives a message (e.g. locally, via UDP, TCP or in whatever else way), +it places these messages into the main message queue. Later, it is +dequeued by the rule processor, which then evaluates which actions are +to be carried out. In front of each action, there is also a queue, which +potentially de-couples the filter processing from the actual action +(e.g. writing to file, database or forwarding to another host). + +Where are Queues Used? +---------------------- + +Currently, queues are used for the main message queue and for the +actions. + +There is a single main message queue inside rsyslog. Each input module +delivers messages to it. The main message queue worker filters messages +based on rules specified in rsyslog.conf and dispatches them to the +individual action queues. Once a message is in an action queue, it is +deleted from the main message queue. + +There are multiple action queues, one for each configured action. By +default, these queues operate in direct (non-queueing) mode. Action +queues are fully configurable and thus can be changed to whatever is +best for the given use case. + +Future versions of rsyslog will most probably utilize queues at other +places, too. + +Wherever "*<object>*\ " is used in the config file statements, +substitute "*<object>*\ " with either "MainMsg" or "Action". The former +will set main message queue parameters, the later parameters for the +next action that will be created. Action queue parameters can not be +modified once the action has been specified. For example, to tell the +main message queue to save its content on shutdown, use +*$MainMsgQueueSaveOnShutdown on*". + +If the same parameter is specified multiple times before a queue is +created, the last one specified takes precedence. The main message queue +is created after parsing the config file and all of its potential +includes. An action queue is created each time an action selector is +specified. Action queue parameters are reset to default after an action +queue has been created (to provide a clean environment for the next +action). + +Not all queues necessarily support the full set of queue configuration +parameters, because not all are applicable. For example, disk queues +always have exactly one worker thread. This cannot be overridden by +configuration parameters. Tries to do so are ignored. + +Queue Modes +----------- + +Rsyslog supports different queue modes, some with submodes. Each of them +has specific advantages and disadvantages. Selecting the right queue +mode is quite important when tuning rsyslogd. The queue mode (aka +"type") is set via the "*$<object>QueueType*\ " config directive. + +Direct Queues +~~~~~~~~~~~~~ + +Direct queues are **non**-queuing queues. A queue in direct mode does +neither queue nor buffer any of the queue elements but rather passes the +element directly (and immediately) from the producer to the consumer. +This sounds strange, but there is a good reason for this queue type. + +Direct mode queues allow to use queues generically, even in places where +queuing is not always desired. A good example is the queue in front of +output actions. While it makes perfect sense to buffer forwarding +actions or database writes, it makes only limited sense to build up a +queue in front of simple local file writes. Yet, rsyslog still has a +queue in front of every action. So for file writes, the queue mode can +simply be set to "direct", in which case no queuing happens. + +Please note that a direct queue also is the only queue type that passes +back the execution return code (success/failure) from the consumer to +the producer. This, for example, is needed for the backup action logic. +Consequently, backup actions require the to-be-checked action to use a +"direct" mode queue. + +To create a direct queue, use the "*$<object>QueueType Direct*\ " config +directive. + +Disk Queues +~~~~~~~~~~~ + +Disk queues use disk drives for buffering. The important fact is that +they always use the disk and do not buffer anything in memory. Thus, the +queue is ultra-reliable, but by far the slowest mode. For regular use +cases, this queue mode is not recommended. It is useful if log data is +so important that it must not be lost, even in extreme cases. + +When a disk queue is written, it is done in chunks. Each chunk receives +its individual file. Files are named with a prefix (set via the +"*$<object>QueueFilename*\ " config directive) and followed by a 7-digit +number (starting at one and incremented for each file). Chunks are 10mb +by default, a different size can be set via +the"*$<object>QueueMaxFileSize*\ " config directive. Note that the size +limit is not a sharp one: rsyslog always writes one complete queue +entry, even if it violates the size limit. So chunks are actually a +little bit (usually less than 1k) larger then the configured size. Each +chunk also has a different size for the same reason. If you observe +different chunk sizes, you can relax: this is not a problem. + +Writing in chunks is used so that processed data can quickly be deleted +and is free for other uses - while at the same time keeping no +artificial upper limit on disk space used. If a disk quota is set +(instructions further below), be sure that the quota/chunk size allows +at least two chunks to be written. Rsyslog currently does not check that +and will fail miserably if a single chunk is over the quota. + +Creating new chunks costs performance but provides quicker ability to +free disk space. The 10mb default is considered a good compromise +between these two. However, it may make sense to adapt these settings to +local policies. For example, if a disk queue is written on a dedicated +200gb disk, it may make sense to use a 2gb (or even larger) chunk size. + +Please note, however, that the disk queue by default does not update its +housekeeping structures every time it writes to disk. This is for +performance reasons. In the event of failure, data will still be lost +(except when manually is mangled with the file structures). However, +disk queues can be set to write bookkeeping information on checkpoints +(every n records), so that this can be made ultra-reliable, too. If the +checkpoint interval is set to one, no data can be lost, but the queue is +exceptionally slow. + +Each queue can be placed on a different disk for best performance and/or +isolation. This is currently selected by specifying different +*$WorkDirectory* config directives before the queue creation statement. + +To create a disk queue, use the "*$<object>QueueType Disk*\ " config +directive. Checkpoint intervals can be specified via +"*$<object>QueueCheckpointInterval*\ ", with 0 meaning no checkpoints. +Note that disk-based queues can be made very reliable by issuing a +(f)sync after each write operation. Starting with version 4.3.2, this +can be requested via "*<object>QueueSyncQueueFiles on/off* with the +default being off. Activating this option has a performance penalty, so +it should not be turned on without reason. + +If you happen to lose or otherwise need the housekeeping structures and +have all yours queue chunks you can use perl script included in rsyslog +package to generate it. +Usage: recover_qi.pl -w *$WorkDirectory* -f QueueFileName -d 8 > QueueFileName.qi + + +In-Memory Queues +~~~~~~~~~~~~~~~~ + +In-memory queue mode is what most people have on their mind when they +think about computing queues. Here, the enqueued data elements are held +in memory. Consequently, in-memory queues are very fast. But of course, +they do not survive any program or operating system abort (what usually +is tolerable and unlikely). Be sure to use an UPS if you use in-memory +mode and your log data is important to you. Note that even in-memory +queues may hold data for an infinite amount of time when e.g. an output +destination system is down and there is no reason to move the data out +of memory (lying around in memory for an extended period of time is NOT +a reason). Pure in-memory queues can't even store queue elements +anywhere else than in core memory. + +There exist two different in-memory queue modes: LinkedList and +FixedArray. Both are quite similar from the user's point of view, but +utilize different algorithms. + +A FixedArray queue uses a fixed, pre-allocated array that holds pointers +to queue elements. The majority of space is taken up by the actual user +data elements, to which the pointers in the array point. The pointer +array itself is comparatively small. However, it has a certain memory +footprint even if the queue is empty. As there is no need to dynamically +allocate any housekeeping structures, FixedArray offers the best run +time performance (uses the least CPU cycle). FixedArray is best if there +is a relatively low number of queue elements expected and performance is +desired. It is the default mode for the main message queue (with a limit +of 10,000 elements). + +A LinkedList queue is quite the opposite. All housekeeping structures +are dynamically allocated (in a linked list, as its name implies). This +requires somewhat more runtime processing overhead, but ensures that +memory is only allocated in cases where it is needed. LinkedList queues +are especially well-suited for queues where only occasionally a +than-high number of elements need to be queued. A use case may be +occasional message burst. Memory permitting, it could be limited to e.g. +200,000 elements which would take up only memory if in use. A FixedArray +queue may have a too large static memory footprint in such cases. + +**In general, it is advised to use LinkedList mode if in doubt**. The +processing overhead compared to FixedArray is low and may be outweighed by +the reduction in memory use. Paging in most-often-unused pointer array +pages can be much slower than dynamically allocating them. + +To create an in-memory queue, use the "*$<object>QueueType +LinkedList*\ " or "*$<object>QueueType FixedArray*\ " config directive. + +Disk-Assisted Memory Queues +^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +If a disk queue name is defined for in-memory queues (via +*$<object>QueueFileName*), they automatically become "disk-assisted" +(DA). In that mode, data is written to disk (and read back) on an +as-needed basis. + +Actually, the regular memory queue (called the "primary queue") and a +disk queue (called the "DA queue") work in tandem in this mode. Most +importantly, the disk queue is activated if the primary queue is full or +needs to be persisted on shutdown. Disk-assisted queues combine the +advantages of pure memory queues with those of pure disk queues. Under +normal operations, they are very fast and messages will never touch the +disk. But if there is need to, an unlimited amount of messages can be +buffered (actually limited by free disk space only) and data can be +persisted between rsyslogd runs. + +With a DA-queue, both disk-specific and in-memory specific configuration +parameters can be set. From the user's point of view, think of a DA +queue like a "super-queue" which does all within a single queue [from +the code perspective, there is some specific handling for this case, so +it is actually much like a single object]. + +DA queues are typically used to de-couple potentially long-running and +unreliable actions (to make them reliable). For example, it is +recommended to use a disk-assisted linked list in-memory queue in front +of each database and "send via tcp" action. Doing so makes these actions +reliable and de-couples their potential low execution speed from the +rest of your rules (e.g. the local file writes). There is a howto on +`massive database inserts <rsyslog_high_database_rate.html>`_ which +nicely describes this use case. It may even be a good read if you do not +intend to use databases. + +With DA queues, we do not simply write out everything to disk and then +run as a disk queue once the in-memory queue is full. A much smarter +algorithm is used, which involves a "high watermark" and a "low +watermark". Both specify numbers of queued items. If the queue size +reaches high watermark elements, the queue begins to write data elements +to disk. It does so until it reaches the low water mark elements. At +this point, it stops writing until either high water mark is reached +again or the on-disk queue becomes empty, in which case the queue +reverts back to in-memory mode, only. While holding at the low +watermark, new elements are actually enqueued in memory. They are +eventually written to disk, but only if the high water mark is ever +reached again. If it isn't, these items never touch the disk. So even +when a queue runs disk-assisted, there is in-memory data present (this +is a big difference to pure disk queues!). + +This algorithm prevents unnecessary disk writes, but also leaves some +additional buffer space for message bursts. Remember that creating disk +files and writing to them is a lengthy operation. It is too lengthy to +e.g. block receiving UDP messages. Doing so would result in message +loss. Thus, the queue initiates DA mode, but still is able to receive +messages and enqueue them - as long as the maximum queue size is not +reached. The number of elements between the high water mark and the +maximum queue size serves as this "emergency buffer". Size it according +to your needs, if traffic is very bursty you will probably need a large +buffer here. Keep in mind, though, that under normal operations these +queue elements will probably never be used. Setting the high water mark +too low will cause disk-assistance to be turned on more often than +actually needed. + +The water marks can be set via the "*$<object>QueueHighWatermark*\ " +and "*$<object>QueueLowWatermark*\ " configuration file directives. +Note that these are actual numbers, not percentages. Be sure they make +sense (also in respect to "*$<object>QueueSize*\ "). Rsyslogd does +perform some checks on the numbers provided, and issues warning when +numbers are "suspicious". + +Limiting the Queue Size +----------------------- + +All queues, including disk queues, have a limit of the number of +elements they can enqueue. This is set via the "*$<object>QueueSize*\ " +config parameter. Note that the size is specified in number of enqueued +elements, not their actual memory size. Memory size limits can not be +set. A conservative assumption is that a single syslog messages takes up +512 bytes on average (in-memory, NOT on the wire, this \*is\* a +difference). + +Disk assisted queues are special in that they do **not** have any size +limit. The enqueue an unlimited amount of elements. To prevent running +out of space, disk and disk-assisted queues can be size-limited via the +"*$<object>QueueMaxDiskSpace*\ " configuration parameter. If it is not +set, the limit is only available free space (and reaching this limit is +currently not very gracefully handled, so avoid running into it!). If a +limit is set, the queue can not grow larger than it. Note, however, that +the limit is approximate. The engine always writes complete records. As +such, it is possible that slightly more than the set limit is used +(usually less than 1k, given the average message size). Keeping strictly +on the limit would be a performance hurt, and thus the design decision +was to favour performance. If you don't like that policy, simply specify +a slightly lower limit (e.g. 999,999K instead of 1G). + +In general, it is a good idea to limit the physical disk space even if +you dedicate a whole disk to rsyslog. That way, you prevent it from +running out of space (future version will have an auto-size-limit logic, +that then kicks in in such situations). + +Worker Thread Pools +------------------- + +Each queue (except in "direct" mode) has an associated pool of worker +threads. Worker threads carry out the action to be performed on the data +elements enqueued. As an actual sample, the main message queue's worker +task is to apply filter logic to each incoming message and enqueue them +to the relevant output queues (actions). + +Worker threads are started and stopped on an as-needed basis. On a +system without activity, there may be no worker at all running. One is +automatically started when a message comes in. Similarly, additional +workers are started if the queue grows above a specific size. The +"*$<object>QueueWorkerThreadMinimumMessages*\ " config parameter +controls worker startup. If it is set to the minimum number of elements +that must be enqueued in order to justify a new worker startup. For +example, let's assume it is set to 100. As long as no more than 100 +messages are in the queue, a single worker will be used. When more than +100 messages arrive, a new worker thread is automatically started. +Similarly, a third worker will be started when there are at least 300 +messages, a forth when reaching 400 and so on. + +It, however, does not make sense to have too many worker threads running +in parallel. Thus, the upper limit can be set via +"*$<object>QueueWorkerThreads*\ ". If it, for example, is set to four, +no more than four workers will ever be started, no matter how many +elements are enqueued. + +Worker threads that have been started are kept running until an +inactivity timeout happens. The timeout can be set via +"*$<object>QueueWorkerTimeoutThreadShutdown*\ " and is specified in +milliseconds. If you do not like to keep the workers running, simply set +it to 0, which means immediate timeout and thus immediate shutdown. But +consider that creating threads involves some overhead, and this is why +we keep them running. If you would like to never shutdown any worker +threads, specify -1 for this parameter. + +Discarding Messages +~~~~~~~~~~~~~~~~~~~ + +If the queue reaches the so called "discard watermark" (a number of +queued elements), less important messages can automatically be +discarded. This is in an effort to save queue space for more important +messages, which you even less like to lose. Please note that whenever +there are more than "discard watermark" messages, both newly incoming as +well as already enqueued low-priority messages are discarded. The +algorithm discards messages newly coming in and those at the front of +the queue. + +The discard watermark is a last resort setting. It should be set +sufficiently high, but low enough to allow for large message burst. +Please note that it take effect immediately and thus shows effect +promptly - but that doesn't help if the burst mainly consist of +high-priority messages... + +The discard watermark is set via the "*$<object>QueueDiscardMark*\ " +directive. The priority of messages to be discarded is set via +"*$<object>QueueDiscardSeverity*\ ". This directive accepts both the +usual textual severity as well as a numerical one. To understand it, you +must be aware of the numerical severity values. They are defined in RFC +3164: + + ==== ======== + Code Severity + ==== ======== + 0 Emergency: system is unusable + 1 Alert: action must be taken immediately + 2 Critical: critical conditions + 3 Error: error conditions + 4 Warning: warning conditions + 5 Notice: normal but significant condition + 6 Informational: informational messages + 7 Debug: debug-level messages + ==== ======== + +Anything of the specified severity and (numerically) above it is +discarded. To turn message discarding off, simply specify the discard +watermark to be higher than the queue size. An alternative is to specify +the numerical value 8 as DiscardSeverity. This is also the default +setting to prevent unintentional message loss. So if you would like to +use message discarding, you need to set" +*$<object>QueueDiscardSeverity*" to an actual value. + +An interesting application is with disk-assisted queues: if the discard +watermark is set lower than the high watermark, message discarding will +start before the queue becomes disk-assisted. This may be a good thing +if you would like to switch to disk-assisted mode only in cases where it +is absolutely unavoidable and you prefer to discard less important +messages first. + +Filled-Up Queues +---------------- + +If the queue has either reached its configured maximum number of entries +or disk space, it is finally full. If so, rsyslogd throttles the data +element submitter. If that, for example, is a reliable input (TCP, local +log socket), that will slow down the message originator which is a good +resolution for this scenario. + +During throttling, a disk-assisted queue continues to write to disk and +messages are also discarded based on severity as well as regular +dequeuing and processing continues. So chances are good the situation +will be resolved by simply throttling. Note, though, that throttling is +highly undesirable for unreliable sources, like UDP message reception. +So it is not a good thing to run into throttling mode at all. + +We can not hold processing infinitely, not even when throttling. For +example, throttling the local log socket too long would cause the +system at whole come to a standstill. To prevent this, rsyslogd times +out after a configured period ("*$<object>QueueTimeoutEnqueue*\ ", +specified in milliseconds) if no space becomes available. As a last +resort, it then discards the newly arrived message. + +If you do not like throttling, set the timeout to 0 - the message will +then immediately be discarded. If you use a high timeout, be sure you +know what you do. If a high main message queue enqueue timeout is set, +it can lead to something like a complete hang of the system. The same +problem does not apply to action queues. + +Rate Limiting +~~~~~~~~~~~~~ + +Rate limiting provides a way to prevent rsyslogd from processing things +too fast. It can, for example, prevent overrunning a receiver system. + +Currently, there are only limited rate-limiting features available. The +"*$<object>QueueDequeueSlowdown*\ " directive allows to specify how +long (in microseconds) dequeueing should be delayed. While simple, it +still is powerful. For example, using a DequeueSlowdown delay of 1,000 +microseconds on a UDP send action ensures that no more than 1,000 +messages can be sent within a second (actually less, as there is also +some time needed for the processing itself). + +Processing Timeframes +~~~~~~~~~~~~~~~~~~~~~ + +Queues can be set to dequeue (process) messages only during certain +timeframes. This is useful if you, for example, would like to transfer +the bulk of messages only during off-peak hours, e.g. when you have only +limited bandwidth on the network path to the central server. + +Currently, only a single timeframe is supported and, even worse, it can +only be specified by the hour. It is not hard to extend rsyslog's +capabilities in this regard - it was just not requested so far. So if +you need more fine-grained control, let us know and we'll probably +implement it. There are two configuration directives, both should be +used together or results are unpredictable:" +*$<object>QueueDequeueTimeBegin <hour>*" +and "*$<object>QueueDequeueTimeEnd <hour>*\ ". The hour parameter must +be specified in 24-hour format (so 10pm is 22). A use case for this +parameter can be found in the `rsyslog +wiki <http://wiki.rsyslog.com/index.php/OffPeakHours>`_. + +Performance +~~~~~~~~~~~ + +The locking involved with maintaining the queue has a potentially large +performance impact. How large this is, and if it exists at all, depends +much on the configuration and actual use case. However, the queue is +able to work on so-called "batches" when dequeueing data elements. With +batches, multiple data elements are dequeued at once (with a single +locking call). The queue dequeues all available elements up to a +configured upper limit (*<object>DequeueBatchSize <number>*). It is +important to note that the actual upper limit is dictated by +availability. The queue engine will never wait for a batch to fill. So +even if a high upper limit is configured, batches may consist of fewer +elements, even just one, if there are no more elements waiting in the +queue. + +Batching can improve performance considerably. Note, however, that it +affects the order in which messages are passed to the queue worker +threads, as each worker now receive as batch of messages. Also, the +larger the batch size and the higher the maximum number of permitted +worker threads, the more main memory is needed. For a busy server, large +batch sizes (around 1,000 or even more elements) may be useful. Please +note that with batching, the main memory must hold BatchSize \* +NumOfWorkers objects in memory (worst-case scenario), even if running in +disk-only mode. So if you use the default 5 workers at the main message +queue and set the batch size to 1,000, you need to be prepared that the +main message queue holds up to 5,000 messages in main memory **in +addition** to the configured queue size limits! + +The queue object's default maximum batch size is eight, but there exists +different defaults for the actual parts of rsyslog processing that +utilize queues. So you need to check these object's defaults. + +Terminating Queues +~~~~~~~~~~~~~~~~~~ + +Terminating a process sounds easy, but can be complex. Terminating a +running queue is in fact the most complex operation a queue object can +perform. You don't see that from a user's point of view, but its quite +hard work for the developer to do everything in the right order. + +The complexity arises when the queue has still data enqueued when it +finishes. Rsyslog tries to preserve as much of it as possible. As a +first measure, there is a regular queue time out +("*$<object>QueueTimeoutShutdown*\ ", specified in milliseconds): the +queue workers are given that time period to finish processing the queue. + +If after that period there is still data in the queue, workers are +instructed to finish the current data element and then terminate. This +essentially means any other data is lost. There is another timeout +("*$<object>QueueTimeoutActionCompletion*\ ", also specified in +milliseconds) that specifies how long the workers have to finish the +current element. If that timeout expires, any remaining workers are +cancelled and the queue is brought down. + +If you do not like to lose data on shutdown, the +"*$<object>QueueSaveOnShutdown*\ " parameter can be set to "on". This +requires either a disk or disk-assisted queue. If set, rsyslogd ensures +that any queue elements are saved to disk before it terminates. This +includes data elements there were begun being processed by workers that +needed to be cancelled due to too-long processing. For a large queue, +this operation may be lengthy. No timeout applies to a required shutdown +save. diff --git a/source/concepts/rfc5424layers.png b/source/concepts/rfc5424layers.png Binary files differnew file mode 100644 index 0000000..70192cc --- /dev/null +++ b/source/concepts/rfc5424layers.png diff --git a/source/conf.py b/source/conf.py new file mode 100644 index 0000000..38a8d47 --- /dev/null +++ b/source/conf.py @@ -0,0 +1,423 @@ +# -*- coding: utf-8 -*- +# +# Rsyslog Doc documentation build configuration file, created by +# sphinx-quickstart on Sun Apr 28 07:10:10 2013. +# +# This file is execfile()d with the current directory set to its containing dir. +# +# Note that not all possible configuration values are present in this +# autogenerated file. +# +# All configuration values have a default; values that are commented out +# serve to show the default. + +import os +import sys + +# Module for our custom functions. Used with automating build info. +sys.path.append(os.getcwd()) +import conf_helpers + + +# If extensions (or modules to document with autodoc) are in another directory, +# add these directories to sys.path here. If the directory is relative to the +# documentation root, use os.path.abspath to make it absolute, like shown here. +#sys.path.insert(0, os.path.abspath('.')) +sys.path.insert(0, os.path.abspath('_ext')) + +# -- General configuration ----------------------------------------------------- + +# If your documentation needs a minimal Sphinx version, state it here. +needs_sphinx = '1.5.1' + +# Add any Sphinx extension module names here, as strings. They can be extensions +# coming with Sphinx (named 'sphinx.ext.*') or your custom ones. +extensions = ['edit_on_github', 'sphinx.ext.todo'] +edit_on_github_project = 'rsyslog/rsyslog-doc' +edit_on_github_branch = 'master' + +# Add any paths that contain templates here, relative to this directory. +templates_path = ['_templates'] + +# The suffix of source filenames. +source_suffix = '.rst' + +# The encoding of source files. +#source_encoding = 'utf-8-sig' + +# The master toctree document. +master_doc = 'index' + +# General information about the project. +project = u'rsyslog' +copyright = u'2008-2022, Rainer Gerhards and Others' +author = u'Rainer Gerhards and Others' + + +# https://stackoverflow.com/questions/26242919/sphinx-documentation-system-multiple-substitutions-with-rst-prolog +# http://www.sphinx-doc.org/en/stable/config.html#confval-rst_prolog +# +# This will be included at the beginning of every source file that is read. +# +# Note: We intentionally include a few substitution definitions directly +# so that the placeholders used here can be replaced by Python's +# string format method. +rst_prolog = """ + +.. |DOC_BUILD| replace:: ``{doc_build}`` +.. |DOC_COMMIT| replace:: ``{doc_commit}`` +.. |DOC_BRANCH| replace:: ``{doc_branch}`` + +.. include:: /includes/substitution_definitions.inc.rst + +""" + +# http://www.sphinx-doc.org/en/stable/config.html#confval-rst_epilog +# This will be included at the end of every source file that is read. +rst_epilog = """ + +.. include:: /includes/footer.inc.rst + +""" + + + + + +############################################################################### +# Placeholder/template values to be filled in by the release_build.sh script +# +# These values are filled in as part of preparing the official docs +# distribution tarball. If the placeholder values are left intact then +# real values will be generated dynamically from info in the repo. If the +# user builds the docs from "bare" sources not yet processed +############################################################################### +version = '8.2402' +release = '8.2402.0' +#release = version + ' daily stable' + +# For this to be true, it means that we are not attempting to build from +# a release tarball, as otherwise the values above would have been replaced +# with official stable release values. +if version == '8': + + # Confirm that a .git folder is available. If not, skip all + # following steps intended to generate daily stable build values for + # 'version' and 'release' build configuration variables. In that + # case, keep the placeholder values already set. + + # The directory where this conf.py file is located + source_conf_dir = os.getcwd() + + # If building from a Git repo, then this directory should be present + # in the parent directory. + git_dir = \ + os.path.abspath(os.path.join(os.getcwd(), os.pardir)) \ + + os.sep + '.git' + + if os.path.isdir(git_dir): + + # If the 'version' variable is left with a placeholder it means + # that this build configuration is being called from a Git repo + # and that we should pull info from the repo to dynamically + # fill in values that were not specified by a build script. + release_type = 'dev' + + # Valid options are "simple" and "detailed". "Simple" contains a short + # dev build string intended for space constrained display. "Detailed" + # contains a much longer dev build string intended for output that is + # used for for copyediting/proofreading, where the generated docs may + # hang around a while before being disposed of. In that situation, + # having detailed build details in the doc are useful to help + # differentiate multiple document builds (even from different branches) + # from each other. + #release_string_detail = 'detailed' + release_string_detail = 'simple' + + # Some items in the source are wrapped with the ".. only:: TAG_NAME_HERE" + # Sphinx directive. This directive prevents the wrapped block of markup + # from being processed unless the specified tag is set. Using this approach + # helps to specific content from being included in stable release docs + # that is only intended for dev/review copies of the documentation. + tags.add(release_type) + + # The version info for the project you're documenting, acts as replacement for + # |version| and |release|, also used in various other places throughout the + # built documents. + # + # The short X.Y version. + version = conf_helpers.get_next_stable_version() + + # This is displayed in multiple prominent locations in the docs + # where it is useful to be able to tell at a glance when the files + # were generated and from what commit. + # + # The full version, including alpha/beta/rc tags. + release = conf_helpers.get_release_string( + release_type, + release_string_detail, + version) + + + # Additions that are used by dev builds + rst_prolog = rst_prolog.format( + doc_build=release, + doc_commit=conf_helpers.get_current_commit_hash(), + doc_branch=conf_helpers.get_current_branch() + ) + +# Disable use of dev build logic, fall back to standard release string values. +else: + release_type = 'stable' + + +# The language for content autogenerated by Sphinx. Refer to documentation +# for a list of supported languages. +#language = None + +# There are two options for replacing |today|: either, you set today to some +# non-false value, then it is used: +#today = '' +# Else, today_fmt is used as the format for a strftime call. +#today_fmt = '%B %d, %Y' + +# List of patterns, relative to source directory, that match files and +# directories to ignore when looking for source files. +# +# Note: We list the *.inc.rst filename pattern here so that matching +# files will not be parsed as separate files to include directly into +# the documentation structure in addition to them being pulled in via +# include statements. Even with include files having been moved to the +# 'source/includes' directory the wildcard pattern has been kept to +# help rule out any issues should an include file be purposely moved +# to the root of the 'source' directory (seen a '/' by Sphinx). +exclude_patterns = ['*.inc.rst', 'includes'] + + +# The reST default role (used for this markup: `text`) to use for all documents. +#default_role = None + +# If true, '()' will be appended to :func: etc. cross-reference text. +#add_function_parentheses = True + +# If true, the current module name will be prepended to all description +# unit titles (such as .. function::). +#add_module_names = True + +# If true, sectionauthor and moduleauthor directives will be shown in the +# output. They are ignored by default. +#show_authors = False + +# The name of the Pygments (syntax highlighting) style to use. +pygments_style = 'sphinx' + +# A list of ignored prefixes for module index sorting. +#modindex_common_prefix = [] + +# Warn about all references where the target cannot be found. Default is False. +nitpicky = True + +# If true, `todo` and `todoList` produce output, else they produce nothing. +todo_include_todos = True + +# If this is True, todo emits a warning for each TODO entries. The default +# is False. +todo_emit_warnings = True + +# Supress "unknown mimetype for ..." warnings +suppress_warnings = ['epub.unknown_project_files'] + +# -- Options for HTML output --------------------------------------------------- + +# The theme to use for HTML and HTML Help pages. See the documentation for +# a list of builtin themes. +html_theme = 'default' +#html_theme = 'basic' +#html_style = 'rsyslog.css' + +# Theme options are theme-specific and customize the look and feel of a theme +# further. For a list of options available for each theme, see the +# documentation. +#html_theme_options = {} + +# Add any paths that contain custom themes here, relative to this directory. +#html_theme_path = [] + +# The name for this set of Sphinx documents. If None, it defaults to +# "<project> v<release> documentation". +if release_type == 'dev': + + html_title = "{} {} docs".format( + project, + conf_helpers.get_release_string( + release_type, release_string_detail, version) + ) + +# A shorter title for the navigation bar. Default is the same as html_title. +#html_short_title = None + +# The name of an image file (relative to this directory) to place at the top +# of the sidebar. +#html_logo = None + +# The name of an image file (within the static path) to use as favicon of the +# docs. This file should be a Windows icon file (.ico) being 16x16 or 32x32 +# pixels large. +#html_favicon = None + +# Add any paths that contain custom static files (such as style sheets) here, +# relative to this directory. They are copied after the builtin static files, +# so a file named "default.css" will overwrite the builtin "default.css". +html_static_path = ['_static'] + +# If not '', a 'Last updated on:' timestamp is inserted at every page bottom, +# using the given strftime format. +#html_last_updated_fmt = '%b %d, %Y' + +# If true, SmartyPants will be used to convert quotes and dashes to +# typographically correct entities. +#html_use_smartypants = True + +# Custom sidebar templates, maps document names to template names. +#html_sidebars = {} + +# Additional templates that should be rendered to pages, maps page names to +# template names. +#html_additional_pages = {} + +# If false, no module index is generated. +#html_domain_indices = True + +# If false, no index is generated. +#html_use_index = True + +# If true, the index is split into individual pages for each letter. +#html_split_index = False + +# If true, links to the reST sources are added to the pages. +#html_show_sourcelink = True + +# If true, "Created using Sphinx" is shown in the HTML footer. Default is True. +html_show_sphinx = False + +# If true, "(C) Copyright ..." is shown in the HTML footer. Default is True. +html_show_copyright = False + +# If true, an OpenSearch description file will be output, and all pages will +# contain a <link> tag referring to it. The value of this option must be the +# base URL from which the finished HTML is served. +#html_use_opensearch = '' + +# This is the file name suffix for HTML files (e.g. ".xhtml"). +#html_file_suffix = None + +# Output file base name for HTML help builder. +htmlhelp_basename = 'rsyslogdoc' + + +# -- Options for LaTeX output -------------------------------------------------- + +latex_elements = { +# The paper size ('letterpaper' or 'a4paper'). +#'papersize': 'letterpaper', + +# The font size ('10pt', '11pt' or '12pt'). +#'pointsize': '10pt', + +# Additional stuff for the LaTeX preamble. +#'preamble': '', +} + +# Grouping the document tree into LaTeX files. List of tuples +# (source start file, target name, title, author, documentclass [howto/manual]). +latex_documents = [ + ('index', 'RsyslogDoc.tex', u'Rsyslog Doc Documentation', + u'foo bar', 'manual'), +] + +# The name of an image file (relative to this directory) to place at the top of +# the title page. +#latex_logo = None + +# For "manual" documents, if this is true, then toplevel headings are parts, +# not chapters. +#latex_use_parts = False + +# If true, show page references after internal links. +#latex_show_pagerefs = False + +# If true, show URL addresses after external links. +#latex_show_urls = False + +# Documents to append as an appendix to all manuals. +#latex_appendices = [] + +# If false, no module index is generated. +#latex_domain_indices = True + + +# -- Options for manual page output -------------------------------------------- + +# One entry per manual page. List of tuples +# (source start file, name, description, authors, manual section). +man_pages = [ + ('queues', 'rsyslog-queues', u'Rsyslog Documentation: Queues', + [u'Rainer Gerhards'], 1), + ('configuration/actions', 'rsyslog-actions', u'Rsyslog Documentation: Actions', + [u'Rainer Gerhards'], 1), +] + +# If true, show URL addresses after external links. +#man_show_urls = False + + +# -- Options for Texinfo output ------------------------------------------------ + +# Grouping the document tree into Texinfo files. List of tuples +# (source start file, target name, title, author, +# dir menu entry, description, category) +texinfo_documents = [ + ('index', 'RsyslogDoc', u'Rsyslog Doc Documentation', + u'foo bar', 'RsyslogDoc', 'One line description of project.', + 'Miscellaneous'), +] + +# Documents to append as an appendix to all manuals. +#texinfo_appendices = [] + +# If false, no module index is generated. +#texinfo_domain_indices = True + +# How to display URL addresses: 'footnote', 'no', or 'inline'. +# texinfo_show_urls = 'footnote' + + +# -- Options for epub output --------------------------------------------------- + +# Use detailed build strings for epub format IF this is a dev build +# and NOT a stable build (which does not use detailed release strings) +if release_type == 'dev': + + # Override "simple" dev build string for epub format + release_string_detail = 'detailed' + + epub_title = "{} {} docs".format( + project, + conf_helpers.get_release_string( + release_type, + release_string_detail, version + ) + ) + +epub_theme = 'epub' +epub_basename = project +epub_author = author +epub_contributor = u'Rsyslog Community' +epub_publisher = 'http://www.rsyslog.com/' +epub_description = u'Documentation for the rsyslog project' + + +# http://www.sphinx-doc.org/en/stable/extdev/appapi.html#sphinx.application.Sphinx.add_stylesheet +# Include our custom stylesheet in addition to specified theme +def setup(app): + app.add_css_file('rsyslog.css') diff --git a/source/conf_helpers.py b/source/conf_helpers.py new file mode 100644 index 0000000..202c0bf --- /dev/null +++ b/source/conf_helpers.py @@ -0,0 +1,129 @@ +# Helper functions for main conf.py Sphinx build configuration + +import datetime +import re +import subprocess + +def get_current_branch(): + """Return the current branch we are on or the branch that the detached head + is pointed to""" + + current_branch = subprocess.check_output( + ['git', 'rev-parse', '--abbrev-ref', "HEAD"] + ).decode("utf-8").strip() + + if current_branch == 'HEAD': + # This means we are operating in a detached head state, will need to + # parse out the branch that the commit is from. + + # Decode "bytes" type to UTF-8 sting to avoid Python 3 error: + # "TypeError: a bytes-like object is required, not 'str'"" + # https://docs.python.org/3/library/stdtypes.html#bytes.decode + branches = subprocess.check_output(['git', 'branch']).decode('utf-8').split('\n') + for branch in branches: + + # Git marks the current branch, or in this case the branch + # we are currently detached from with an asterisk + if '*' in branch: + # Split on the remote/branch separator, grab the + # last entry in the list and then strip off the trailing + # parentheis + detached_from_branch = branch.split('/')[-1].replace(')', '') + + return detached_from_branch + + else: + # The assumption is that we are on a branch at this point. Return that. + return current_branch + + +def get_current_stable_version(): + """Return the current X.Y stable version number from the latest git tag""" + + def get_latest_tag(): + """"Helper function: Return the latest git tag""" + + git_tag_output = subprocess.check_output( + ['git', 'tag', '--list', "v*"] + ).decode("utf-8").strip() + + git_tag_list = re.sub('[A-Za-z]', '', git_tag_output).split('\n') + git_tag_list.sort(key=lambda s: [int(u) for u in s.split('.')]) + + # The latest tag is the last in the list + git_tag_latest = git_tag_list[-1] + + return git_tag_latest + + latest_tag = get_latest_tag() + + # Return 'X.Y' from 'X.Y.Z' + return latest_tag[:-2] + + +def get_next_stable_version(): + """Return the next stable version""" + + current_version = get_current_stable_version() + + # Break apart 'x.y' value, increment y and then concatenate into 'x.y' again + next_version = "{}.{}".format( + int(current_version[:1]), + int(current_version[-2:]) + 1 + ) + + return next_version + + +def get_current_commit_hash(): + """Return commit hash string""" + + commit_hash = subprocess.check_output(['git', 'log', '--pretty=format:%h', 'HEAD', '-n1']).decode("utf-8") + + return commit_hash + + +def get_release_string(release_type, release_string_detail, version): + """Return a release string representing the type of build. Verbose for + dev builds and with sparse version info for release builds""" + + if release_type == "dev": + + # Used in dev builds + DATE = datetime.date.today() + TODAY = DATE.strftime('%Y%m%d') + + # The detailed release string is too long for the rsyslog.com 'better' + # theme and perhaps too long for other themes as well, so we set the + # level to 'simple' by default (to be explicit) and + # allow overriding by command-line if desired. + if release_string_detail == "simple": + + # 'rsyslog' prefix is already set via 'project' variable in conf.py + # HASH + # 'docs' string suffix is already ... + release_string = "{}".format( + get_current_commit_hash() + ) + elif release_string_detail == "detailed": + + # The verbose variation of the release string. This was previously + # the default when using the 'classic' theme, but proves to be + # too long when viewed using alternate themes. If requested + # via command-line override this format is used. + release_string = "{}-{}-{}-{}".format( + get_next_stable_version(), + get_current_branch(), + TODAY, + get_current_commit_hash() + ) + else: + # This means that someone set a value that we do not + # have a format defined for. Return an error string instead + # to help make it clear what happened. + release_string = "invalid value for release_string_detail" + + else: + release_string = "{}".format(version) + + return release_string diff --git a/source/conf_helpers.pyc b/source/conf_helpers.pyc Binary files differnew file mode 100644 index 0000000..6987d10 --- /dev/null +++ b/source/conf_helpers.pyc diff --git a/source/configuration/.conf_formats.rst.swp b/source/configuration/.conf_formats.rst.swp Binary files differnew file mode 100644 index 0000000..3e9e0cf --- /dev/null +++ b/source/configuration/.conf_formats.rst.swp diff --git a/source/configuration/.templates.rst.swp b/source/configuration/.templates.rst.swp Binary files differnew file mode 100644 index 0000000..3b3805b --- /dev/null +++ b/source/configuration/.templates.rst.swp diff --git a/source/configuration/action/index.rst b/source/configuration/action/index.rst new file mode 100644 index 0000000..e71b7f6 --- /dev/null +++ b/source/configuration/action/index.rst @@ -0,0 +1,193 @@ +Legacy Action-Specific Configuration Statements +=============================================== + +Statements modify the next action(s) that is/are defined **via legacy syntax** +after the respective statement. +Actions defined via the action() object are **not** affected by the +legacy statements listed here. Use the action() object properties +instead. + +Generic action configuration Statements +--------------------------------------- +These statements can be used with all types of actions. + +.. toctree:: + :glob: + + *action* + *rsconf1_repeatedmsgreduction* + +- **$ActionName** <a\_single\_word> - used primarily for documentation, + e.g. when generating a configuration graph. Available since 4.3.1. +- **$ActionExecOnlyOnceEveryInterval** <seconds> - execute action only if + the last execute is at last <seconds> seconds in the past (more info + in `ommail <ommail.html>`_, but may be used with any action). To + disable this setting, use value 0. +- **$ActionExecOnlyEveryNthTime** <number> - If configured, the next + action will only be executed every n-th time. For example, if + configured to 3, the first two messages that go into the action will + be dropped, the 3rd will actually cause the action to execute, the + 4th and 5th will be dropped, the 6th executed under the action, ... + and so on. Note: this setting is automatically re-set when the actual + action is defined. +- **$ActionExecOnlyEveryNthTimeTimeout** <number-of-seconds> - has a + meaning only if $ActionExecOnlyEveryNthTime is also configured for + the same action. If so, the timeout setting specifies after which + period the counting of "previous actions" expires and a new action + count is begun. Specify 0 (the default) to disable timeouts. + *Why is this option needed?* Consider this case: a message comes in + at, eg., 10am. That's count 1. Then, nothing happens for the next 10 + hours. At 8pm, the next one occurs. That's count 2. Another 5 hours + later, the next message occurs, bringing the total count to 3. Thus, + this message now triggers the rule. + The question is if this is desired behavior? Or should the rule only + be triggered if the messages occur within an e.g. 20 minute window? + If the later is the case, you need a + $ActionExecOnlyEveryNthTimeTimeout 1200 + This directive will timeout previous messages seen if they are older + than 20 minutes. In the example above, the count would now be always + 1 and consequently no rule would ever be triggered. +- **$ActionResumeRetryCount** <number> [default 0, -1 means eternal] +- **$ActionWriteAllMarkMessages** [on/**off**]- [available since 5.1.5] + - normally, mark messages are written to actions only if the action + was not recently executed (by default, recently means within the past + 20 minutes). If this setting is switched to "on", mark messages are + always sent to actions, no matter how recently they have been + executed. In this mode, mark messages can be used as a kind of + heartbeat. Note that this option auto-resets to "off", so if you + intend to use it with multiple actions, it must be specified in front + off **all** selector lines that should provide this functionality. + +omfile-specific Configuration Statements +---------------------------------------- +These statements are specific to omfile-based actions. + +.. toctree:: + :glob: + + *omfile* + *dir* + *file* + +- **$CreateDirs** [**on**/off] - create directories on an as-needed + basis +- **$ActionFileDefaultTemplate** [templateName] - sets a new default + template for file actions +- **$ActionFileEnableSync [on/off]** - enables file syncing capability of + omfile +- **$OMFileAsyncWriting** [on/**off**], if turned on, the files will be + written in asynchronous mode via a separate thread. In that case, + double buffers will be used so that one buffer can be filled while + the other buffer is being written. Note that in order to enable + $OMFileFlushInterval, $OMFileAsyncWriting must be set to "on". + Otherwise, the flush interval will be ignored. Also note that when + $OMFileFlushOnTXEnd is "on" but $OMFileAsyncWriting is off, output + will only be written when the buffer is full. This may take several + hours, or even require a rsyslog shutdown. However, a buffer flush + can be forced in that case by sending rsyslogd a HUP signal. +- **$OMFileZipLevel** 0..9 [default 0] - if greater 0, turns on gzip + compression of the output file. The higher the number, the better the + compression, but also the more CPU is required for zipping. +- **$OMFileIOBufferSize** <size\_nbr>, default 4k, size of the buffer + used to writing output data. The larger the buffer, the potentially + better performance is. The default of 4k is quite conservative, it is + useful to go up to 64k, and 128K if you used gzip compression (then, + even higher sizes may make sense) +- **$OMFileFlushOnTXEnd** <[**on**/off]>, default on. Omfile has the + capability to write output using a buffered writer. Disk writes are + only done when the buffer is full. So if an error happens during that + write, data is potentially lost. In cases where this is unacceptable, + set $OMFileFlushOnTXEnd to on. Then, data is written at the end of + each transaction (for pre-v5 this means after **each** log message) + and the usual error recovery thus can handle write errors without + data loss. Note that this option severely reduces the effect of zip + compression and should be switched to off for that use case. Note + that the default -on- is primarily an aid to preserve the traditional + syslogd behaviour. + +omfwd-specific Configuration Statements +--------------------------------------- +These statements are specific to omfwd-based actions. + +- **$ActionForwardDefaultTemplate** [templateName] - sets a new default + template for UDP and plain TCP forwarding action +- **$ActionSendResendLastMsgOnReconnect** <[on/**off**]> specifies if the + last message is to be resend when a connection breaks and has been + reconnected. May increase reliability, but comes at the risk of + message duplication. +- **$ActionSendStreamDriver** <driver basename> just like + $DefaultNetstreamDriver, but for the specific action +- **$ActionSendStreamDriverMode** <mode>, default 0, mode to use with the + stream driver (driver-specific) +- **$ActionSendStreamDriverAuthMode** <mode>, authentication mode to use + with the stream driver. Note that this directive requires TLS + netstream drivers. For all others, it will be ignored. + (driver-specific) +- **$ActionSendStreamDriverPermittedPeer** <ID>, accepted fingerprint + (SHA1) or name of remote peer. Note that this directive requires TLS + netstream drivers. For all others, it will be ignored. + (driver-specific) - directive may go away! +- **$ActionSendTCPRebindInterval** nbr- [available since 4.5.1] - + instructs the TCP send action to close and re-open the connection to + the remote host every nbr of messages sent. Zero, the default, means + that no such processing is done. This directive is useful for use + with load-balancers. Note that there is some performance overhead + associated with it, so it is advisable to not too often "rebind" the + connection (what "too often" actually means depends on your + configuration, a rule of thumb is that it should be not be much more + often than once per second). +- **$ActionSendUDPRebindInterval** nbr- [available since 4.3.2] - + instructs the UDP send action to rebind the send socket every nbr of + messages sent. Zero, the default, means that no rebind is done. This + directive is useful for use with load-balancers. + +omgssapi-specific Configuration Statements +------------------------------------------ +These statements are specific to omgssapi actions. + +.. toctree:: + :glob: + + *gss* + +action-queue specific Configuration Statements +---------------------------------------------- +The following statements specify parameters for the action queue. +To understand queue parameters, read +:doc:`queues in rsyslog <../../concepts/queues>`. + +Action queue parameters usually affect the next action and auto-reset +to defaults thereafter. Most importantly, this means that when a +"real" (non-direct) queue type is defined, this affects the immediately +following action, only. The next and all other actions will be +in "direct" mode (no real queue) if not explicitly specified otherwise. + +- **$ActionQueueCheckpointInterval** <number> +- **$ActionQueueDequeueBatchSize** <number> [default 128] +- **$ActionQueueDequeueSlowdown** <number> [number is timeout in + *micro*\ seconds (1000000us is 1sec!), default 0 (no delay). Simple + rate-limiting!] +- **$ActionQueueDiscardMark** <number> [default 80% of queue size] +- **$ActionQueueDiscardSeverity** <number> [\*numerical\* severity! default + 8 (nothing discarded)] +- **$ActionQueueFileName** <name> +- **$ActionQueueHighWaterMark** <number> [default 90% of queue size] +- **$ActionQueueImmediateShutdown** [on/**off**] +- **$ActionQueueSize** <number> +- **$ActionQueueLowWaterMark** <number> [default 70% of queue size] +- **$ActionQueueMaxFileSize** <size\_nbr>, default 1m +- **$ActionQueueTimeoutActionCompletion** <number> [number is timeout in ms + (1000ms is 1sec!), default 1000, 0 means immediate!] +- **$ActionQueueTimeoutEnqueue** <number> [number is timeout in ms (1000ms + is 1sec!), default 2000, 0 means discard immediately] +- **$ActionQueueTimeoutShutdown** <number> [number is timeout in ms (1000ms + is 1sec!), default 0 (indefinite)] +- **$ActionQueueWorkerTimeoutThreadShutdown** <number> [number is timeout + in ms (1000ms is 1sec!), default 60000 (1 minute)] +- **$ActionQueueType** [FixedArray/LinkedList/**Direct**/Disk] +- **$ActionQueueSaveOnShutdown** [on/**off**] +- **$ActionQueueWorkerThreads** <number>, num worker threads, default 1, + recommended 1 +- $ActionQueueWorkerThreadMinumumMessages <number>, default 100 +- **$ActionGSSForwardDefaultTemplate** [templateName] - sets a new default + template for GSS-API forwarding action diff --git a/source/configuration/action/rsconf1_actionexeconlywhenpreviousissuspended.rst b/source/configuration/action/rsconf1_actionexeconlywhenpreviousissuspended.rst new file mode 100644 index 0000000..11251fe --- /dev/null +++ b/source/configuration/action/rsconf1_actionexeconlywhenpreviousissuspended.rst @@ -0,0 +1,41 @@ +$ActionExecOnlyWhenPreviousIsSuspended +-------------------------------------- + +**Type:** action configuration parameter + +**Default:** off + +**Description:** + +This parameter allows to specify if actions should always be executed +("off," the default) or only if the previous action is suspended ("on"). +This parameter works hand-in-hand with the multiple actions per selector +feature. It can be used, for example, to create rules that automatically +switch destination servers or databases to a (set of) backup(s), if the +primary server fails. Note that this feature depends on proper +implementation of the suspend feature in the output module. All built-in +output modules properly support it (most importantly the database write +and the syslog message forwarder). + +This selector processes all messages it receives (\*.\*). It tries to +forward every message to primary-syslog.example.com (via tcp). If it can +not reach that server, it tries secondary-1-syslog.example.com, if that +fails too, it tries secondary-2-syslog.example.com. If neither of these +servers can be connected, the data is stored in /var/log/localbuffer. +Please note that the secondaries and the local log buffer are only used +if the one before them does not work. So ideally, /var/log/localbuffer +will never receive a message. If one of the servers resumes operation, +it automatically takes over processing again. + +We strongly advise not to use repeated line reduction together with +ActionExecOnlyWhenPreviousIsSuspended. It may lead to "interesting" and +undesired results (but you can try it if you like). + +Example:: + + *.* @@primary-syslog.example.com + $ActionExecOnlyWhenPreviousIsSuspended on + & @@secondary-1-syslog.example.com # & is used to have more than one action for + & @@secondary-2-syslog.example.com # the same selector - the multi-action feature + & /var/log/localbuffer + $ActionExecOnlyWhenPreviousIsSuspended off # to re-set it for the next selector diff --git a/source/configuration/action/rsconf1_actionresumeinterval.rst b/source/configuration/action/rsconf1_actionresumeinterval.rst new file mode 100644 index 0000000..69d2114 --- /dev/null +++ b/source/configuration/action/rsconf1_actionresumeinterval.rst @@ -0,0 +1,26 @@ +$ActionResumeInterval +--------------------- + +**Type:** action configuration parameter + +**Default:** 30 + +**Description:** + +Sets the ActionResumeInterval for all following actions. The interval +provided is always in seconds. Thus, multiply by 60 if you need minutes +and 3,600 if you need hours (not recommended). + +When an action is suspended (e.g. destination can not be connected), the +action is resumed for the configured interval. Thereafter, it is +retried. If multiple retries fail, the interval is automatically +extended. This is to prevent excessive resource use for retries. After +each 10 retries, the interval is extended by itself. To be precise, the +actual interval is (numRetries / 10 + 1) \* $ActionResumeInterval. so +after the 10th try, it by default is 60 and after the 100th try it is +330. + +**Sample:** + +$ActionResumeInterval 30 + diff --git a/source/configuration/action/rsconf1_dirgroup.rst b/source/configuration/action/rsconf1_dirgroup.rst new file mode 100644 index 0000000..c965a43 --- /dev/null +++ b/source/configuration/action/rsconf1_dirgroup.rst @@ -0,0 +1,19 @@ +$DirGroup +--------- + +**Type:** global configuration parameter + +**Default:** + +**Description:** + +Set the group for directories newly created. Please note that this +setting does not affect the group of directories already existing. The +parameter is a group name, for which the groupid is obtained by rsyslogd +on during startup processing. Interim changes to the user mapping are +not detected. + +**Sample:** + +``$DirGroup loggroup`` + diff --git a/source/configuration/action/rsconf1_dirowner.rst b/source/configuration/action/rsconf1_dirowner.rst new file mode 100644 index 0000000..4bb2701 --- /dev/null +++ b/source/configuration/action/rsconf1_dirowner.rst @@ -0,0 +1,19 @@ +$DirOwner +--------- + +**Type:** global configuration parameter + +**Default:** + +**Description:** + +Set the file owner for directories newly created. Please note that this +setting does not affect the owner of directories already existing. The +parameter is a user name, for which the userid is obtained by rsyslogd +during startup processing. Interim changes to the user mapping are not +detected. + +**Sample:** + +``$DirOwner loguser`` + diff --git a/source/configuration/action/rsconf1_dynafilecachesize.rst b/source/configuration/action/rsconf1_dynafilecachesize.rst new file mode 100644 index 0000000..71ddc53 --- /dev/null +++ b/source/configuration/action/rsconf1_dynafilecachesize.rst @@ -0,0 +1,4 @@ +$DynaFileCacheSize +------------------ + +This is an :doc:`omfile <../modules/omfile>` parameter. See there for details. diff --git a/source/configuration/action/rsconf1_filecreatemode.rst b/source/configuration/action/rsconf1_filecreatemode.rst new file mode 100644 index 0000000..63f1ad7 --- /dev/null +++ b/source/configuration/action/rsconf1_filecreatemode.rst @@ -0,0 +1,43 @@ +$FileCreateMode +--------------- + +**Type:** global configuration parameter + +**Default:** 0644 + +**Description:** + +The $FileCreateMode parameter allows to specify the creation mode with +which rsyslogd creates new files. If not specified, the value 0644 is +used (which retains backward-compatibility with earlier releases). The +value given must always be a 4-digit octal number, with the initial +digit being zero. + +Please note that the actual permission depend on rsyslogd's process +umask. If in doubt, use "$umask 0000" right at the beginning of the +configuration file to remove any restrictions. + +$FileCreateMode may be specified multiple times. If so, it specifies the +creation mode for all selector lines that follow until the next +$FileCreateMode parameter. Order of lines is vitally important. + +**Sample:** + +``$FileCreateMode 0600`` + +This sample lets rsyslog create files with read and write access only +for the users it runs under. + +The following sample is deemed to be a complete rsyslog.conf:: + + $umask 0000 # make sure nothing interferes with the following definitions + *.* /var/log/file-with-0644-default + $FileCreateMode 0600 + *.* /var/log/file-with-0600 + $FileCreateMode 0644 + *.* /var/log/file-with-0644 + +As you can see, open modes depend on position in the config file. Note +the first line, which is created with the hardcoded default creation +mode. + diff --git a/source/configuration/action/rsconf1_filegroup.rst b/source/configuration/action/rsconf1_filegroup.rst new file mode 100644 index 0000000..7b33381 --- /dev/null +++ b/source/configuration/action/rsconf1_filegroup.rst @@ -0,0 +1,18 @@ +$FileGroup +---------- + +**Type:** global configuration parameter + +**Default:** + +**Description:** + +Set the group for dynaFiles newly created. Please note that this setting +does not affect the group of files already existing. The parameter is a +group name, for which the groupid is obtained by rsyslogd during startup +processing. Interim changes to the user mapping are not detected. + +**Sample:** + +``$FileGroup loggroup`` + diff --git a/source/configuration/action/rsconf1_fileowner.rst b/source/configuration/action/rsconf1_fileowner.rst new file mode 100644 index 0000000..1ad6a6e --- /dev/null +++ b/source/configuration/action/rsconf1_fileowner.rst @@ -0,0 +1,19 @@ +$FileOwner +---------- + +**Type:** global configuration parameter + +**Default:** + +**Description:** + +Set the file owner for dynaFiles newly created. Please note that this +setting does not affect the owner of files already existing. The +parameter is a user name, for which the userid is obtained by rsyslogd +during startup processing. Interim changes to the user mapping are not +detected. + +**Sample:** + +``$FileOwner loguser`` + diff --git a/source/configuration/action/rsconf1_gssforwardservicename.rst b/source/configuration/action/rsconf1_gssforwardservicename.rst new file mode 100644 index 0000000..c2e2fa1 --- /dev/null +++ b/source/configuration/action/rsconf1_gssforwardservicename.rst @@ -0,0 +1,21 @@ +$GssForwardServiceName +---------------------- + +**Type:** global configuration parameter + +**Default:** host + +**Provided by:** *omgssapi* + +**Description:** + +Specifies the service name used by the client when forwarding GSS-API +wrapped messages. + +The GSS-API service names are constructed by appending '@' and a +hostname following "@@" in each selector. + +**Sample:** + +``$GssForwardServiceName rsyslog`` + diff --git a/source/configuration/action/rsconf1_gssmode.rst b/source/configuration/action/rsconf1_gssmode.rst new file mode 100644 index 0000000..8e3b8b6 --- /dev/null +++ b/source/configuration/action/rsconf1_gssmode.rst @@ -0,0 +1,20 @@ +$GssMode +-------- + +**Type:** global configuration parameter + +**Default:** encryption + +**Provided by:** *omgssapi* + +**Description:** + +Specifies GSS-API mode to use, which can be "**integrity**\ " - clients +are authenticated and messages are checked for integrity, +"**encryption**\ " - same as "integrity", but messages are also +encrypted if both sides support it. + +**Sample:** + +``$GssMode Encryption`` + diff --git a/source/configuration/action/rsconf1_omfileforcechown.rst b/source/configuration/action/rsconf1_omfileforcechown.rst new file mode 100644 index 0000000..5eba119 --- /dev/null +++ b/source/configuration/action/rsconf1_omfileforcechown.rst @@ -0,0 +1,67 @@ +$omfileForceChown +----------------- + +**Type:** action configuration parameter + +**Parameter Values:** boolean (on/off, yes/no) + +**Available:** 4.7.0+, 5.3.0-5.8.x, **NOT** available in 5.9.x or higher + +**Note: this parameter has been removed and is no longer available. The +documentation is currently being retained for historical reaons.** +Expect it to go away at some later stage as well. + +**Default:** off + +**Description:** + +Forces rsyslogd to change the ownership for output files that already +exist. Please note that this tries to fix a potential problem that +exists outside the scope of rsyslog. Actually, it tries to fix invalid +ownership/permission settings set by the original file creator. + +Rsyslog changes the ownership during initial execution with root +privileges. When a privilege drop is configured, privileges are dropped +after the file owner ship is changed. Not that this currently is a +limitation in rsyslog's privilege drop code, which is on the TODO list +to be removed. See Caveats section below for the important implications. + +**Caveats:** + +This parameter tries to fix a problem that actually is outside the scope +of rsyslog. As such, there are a couple of restrictions and situations +in which it will not work. **Users are strongly encouraged to fix their +system instead of turning this parameter on** - it should only be used +as a last resort. + +At least in the following scenario, this parameter will fail expectedly: + +It does not address the situation that someone changes the ownership +\*after\* rsyslogd has started. Let's, for example, consider a log +rotation script. + +- rsyslog is started +- ownership is changed +- privileges dropped +- log rotation (lr) script starts +- lr removes files +- lr creates new files with root:adm (or whatever else) +- lr HUPs rsyslogd +- rsyslogd closes files +- rsyslogd tries to open files +- rsyslogd tries to change ownership --> fail as we are non-root now +- file open fails + +Please note that once the privilege drop code is refactored, this +parameter will no longer work, because then privileges will be dropped +before any action is performed, and thus we will no longer be able to +chown files that do not belong to the user rsyslogd is configured to run +under. + +So **expect the parameter to go away**. It will not be removed in +version 4, but may disappear at any time for any version greater than 4. + +**Sample:** + +``$FileOwner loguser $omfileForceChown on`` + diff --git a/source/configuration/action/rsconf1_repeatedmsgreduction.rst b/source/configuration/action/rsconf1_repeatedmsgreduction.rst new file mode 100644 index 0000000..33ddeb9 --- /dev/null +++ b/source/configuration/action/rsconf1_repeatedmsgreduction.rst @@ -0,0 +1,70 @@ +$RepeatedMsgReduction +--------------------- + +**Type:** global configuration parameter + +**Default:** off + +Description +^^^^^^^^^^^ + +This parameter models old sysklogd legacy. **Note that many people, +including the rsyslog authors, consider this to be a misfeature.** See +*Discussion* below to learn why. + +This parameter specifies whether or not repeated messages should be +reduced (this is the "Last line repeated n times" feature). If set to +*on*, repeated messages are reduced. If kept at *off*, every message is +logged. In very early versions of rsyslog, this was controlled by the +*-e* command line option. + +What is a repeated message +^^^^^^^^^^^^^^^^^^^^^^^^^^ + +For a message to be classified as repeated, the following properties +must be **identical**: + +* msg +* hostname +* procid +* appname + +Note that rate-limiters are usually applied to specific input sources +or processes. So first and foremost the input source must be the same +to classify a messages as a duplicated. + +You may want to check out +`testing rsyslog ratelimiting <http://www.rsyslog.com/first-try-to-test-rate-limiting/>`_ +for some extra information on the per-process ratelimiting. + +Discussion +^^^^^^^^^^ + +* Very old versions of rsyslog did not have the ability to include the + repeated message itself within the repeat message. + +* Versions before 7.3.2 applied repeat message reduction to the output + side. This had some implications: + + - they did not account for the actual message origin, so two processes + emitting an equally-looking message triggered the repeated message + reduction code + + - repeat message processing could be set on a per-action basis, which + has switched to per-input basis for 7.3.2 and above + +* While turning this feature on can save some space in logs, most log analysis + tools need to see the repeated messages, they can't handle the + "last message repeated" format. +* This is a feature that worked decades ago when logs were small and reviewed + by a human, it fails badly on high volume logs processed by tools. + +Sample +^^^^^^ + +This turns on repeated message reduction (**not** recommended): + +:: + + $RepeatedMsgReduction on # do not log repeated messages + diff --git a/source/configuration/actions.rst b/source/configuration/actions.rst new file mode 100644 index 0000000..31dbce7 --- /dev/null +++ b/source/configuration/actions.rst @@ -0,0 +1,621 @@ +Actions +======= + +.. index:: ! action +.. _cfgobj_input: + +The Action object describe what is to be done with a message. They are +implemented via :doc:`output modules <modules/idx_output>`. + +The action object has different parameters: + +- those that apply to all actions and are action specific. These are + documented below. + +- parameters for the action queue. While they also apply to all + parameters, they are queue-specific, not action-specific (they are + the same that are used in rulesets, for example). The are documented + separately under :doc:`queue parameters <../rainerscript/queue_parameters>`. + +- action-specific parameters. These are specific to a certain type of + actions. They are documented by the :doc:`output modules<modules/idx_output>` + in question. + +General Action Parameters +------------------------- + +Note: parameter names are case-insensitive. + +- **name** word + + This names the action. The name is used for statistics gathering + and documentation. If no name is given, one is dynamically generated + based on the occurrence of this action inside the rsyslog configuration. + Actions are sequentially numbered from 1 to n. + +- **type** string + + Mandatory parameter for every action. The name of the module that + should be used. + +- **action.writeAllMarkMessages** *on*/off + + This setting tells if mark messages are always written ("on", the + default) or only if the action was not recently executed ("off"). By + default, recently means within the past 20 minutes. If this setting + is "on", mark messages are always sent to actions, no matter how + recently they have been executed. In this mode, mark messages can be + used as a kind of heartbeat. This mode also enables faster processing + inside the rule engine. So it should be set to "off" only when there + is a good reason to do so. + +- **action.execOnlyEveryNthTime** integer + + If configured, the next action will only be executed every n-th time. + For example, if configured to 3, the first two messages that go into + the action will be dropped, the 3rd will actually cause the action to + execute, the 4th and 5th will be dropped, the 6th executed under the + action, ... and so on. + +- **action.execOnlyEveryNthTimeout** integer + + Has a meaning only if Action.ExecOnlyEveryNthTime is also configured + for the same action. If so, the timeout setting specifies after which + period the counting of "previous actions" expires and a new action + count is begun. Specify 0 (the default) to disable timeouts. Why is + this option needed? Consider this case: a message comes in at, eg., + 10am. That's count 1. Then, nothing happens for the next 10 hours. At + 8pm, the next one occurs. That's count 2. Another 5 hours later, the + next message occurs, bringing the total count to 3. Thus, this + message now triggers the rule. The question is if this is desired + behavior? Or should the rule only be triggered if the messages occur + within an e.g. 20 minute window? If the later is the case, you need a + Action.ExecOnlyEveryNthTimeTimeout="1200" + This directive will timeout previous messages seen if they are older + than 20 minutes. In the example above, the count would now be always + 1 and consequently no rule would ever be triggered. + +- **action.errorfile** string + + .. versionadded:: 8.32.0 + + When an action is executed, some messages may permanently fail. + Depending on configuration, this could for example be caused by an + offline target or exceptionally non-numerical data inside a + numerical database field. If action.errorfile is specified, those + messages are written to the specified file. If it is not specified + (the default), messages are silently discarded. + + The error file format is JSON. It contains the failed messages as + provided to the action in question, the action name as well as + the rsyslog status code roughly explaining why it failed. + +- **action.errorfile.maxsize** integer + + In some cases, error file needs to be limited in size. + This option allows specifying a maximum size, in bytes, for the error file. + When error file reaches that size, no more errors are written to it. + +- **action.execOnlyOnceEveryInterval** integer + + Execute action only if the last execute is at last seconds in the + past (more info in ommail, but may be used with any action) + +- **action.execOnlyWhenPreviousIsSuspended** on/off + + This directive allows to specify if actions should always be executed + ("off," the default) or only if the previous action is suspended + ("on"). This directive works hand-in-hand with the multiple actions + per selector feature. It can be used, for example, to create rules + that automatically switch destination servers or databases to a (set + of) backup(s), if the primary server fails. Note that this feature + depends on proper implementation of the suspend feature in the output + module. All built-in output modules properly support it (most + importantly the database write and the syslog message forwarder). + Note, however, that a failed action may not immediately be detected. + For more information, see the `rsyslog + execOnlyWhenPreviousIsSuspended + preciseness <https://www.rsyslog.com/action-execonlywhenpreviousissuspended-preciseness/>`_ + FAQ article. + +- **action.repeatedmsgcontainsoriginalmsg** on/off + + "last message repeated n times" messages, if generated, have a + different format that contains the message that is being repeated. + Note that only the first "n" characters are included, with n to be at + least 80 characters, most probably more (this may change from version + to version, thus no specific limit is given). The bottom line is that + n is large enough to get a good idea which message was repeated but + it is not necessarily large enough for the whole message. (Introduced + with 4.1.5). + +- **action.resumeRetryCount** integer + + [default 0, -1 means eternal] + + Sets how often an action is retried before it is considered to have + failed. Failed actions discard messages. + +- **action.resumeInterval** integer + + Sets the action's resume interval. The interval provided + is always in seconds. Thus, multiply by 60 if you need minutes and + 3,600 if you need hours (not recommended). When an action is + suspended (e.g. destination can not be connected), the action is + resumed for the configured interval. Thereafter, it is retried. If + multiple retries fail, the interval is automatically extended. This + is to prevent excessive resource use for retries. After each 10 + retries, the interval is extended by itself. To be precise, the + actual interval is `(numRetries / 10 + 1) * action.resumeInterval`. + Using the default value of 30, this means that on the 10th try the + suspension interval will be 60 (seconds) and after the 100th try + it will be 330 (seconds). + +- **action.resumeIntervalMax** integer + + Default: 1800 (30 minutes) + + This sets an upper limit on the growth of action.resumeInterval. + No wait will be larger than the value configured here. Going higher + than the default is only recommended if you know that a system may + be offline for an extended period of time **and** if it is acceptable + that it may take quite long to detect it came online again. + +- **action.reportSuspension** on/off + + Configures rsyslog to report suspension and reactivation + of the action. This is useful to note which actions have + problems (e.g. connecting to a remote system) and when. + The default for this setting is the equally-named global + parameter. + +- **action.reportSuspensionContinuation** on/off + + Configures rsyslog to report continuation of action suspension. + This emits new messages whenever an action is to be retried, but + continues to fail. If set to "on", *action.reportSuspension* is + also automatically set to "on". + The default for this setting is the equally-named global + parameter. + +- **action.copyMsg** on/*off* + + Configures action to *copy* the message if *on*. Defaults to + *off* (which is how actions have worked traditionally), which + causes queue to refer to the original message object, with + reference-counting. (Introduced with 8.10.0). + +Useful Links +------------ + +- Rainer's blog posting on the performance of `main and action queue + worker + threads <https://rainer.gerhards.net/2013/06/rsyslog-performance-main-and-action.html>`_ + +Legacy Format +------------- + +.. _legacy-action-order: + +**Be warned that legacy action format is hard to get right. It is +recommended to use RainerScript-Style action format whenever possible!** +A key problem with legacy format is that a single action is defined via +multiple configurations lines, which may be spread all across +rsyslog.conf. Even the definition of multiple actions may be intermixed +(often not intentional!). If legacy actions format needs to be used +(e.g. some modules may not yet implement the RainerScript format), it is +strongly recommended to place all configuration statements pertaining to +a single action closely together. + +Please also note that legacy action parameters **do not** affect +RainerScript action objects. So if you define for example: + +:: + + $actionResumeRetryCount 10 + action(type="omfwd" target="server1.example.net") + @@server2.example.net + +server1's "action.resumeRetryCount" parameter is **not** set, instead +server2's is! + +A goal of the new RainerScript action format was to avoid confusion +which parameters are actually used. As such, it would be +counter-productive to honor legacy action parameters inside a +RainerScript definition. As result, both types of action definitions are +strictly (and nicely) separated from each other. The bottom line is that +if RainerScript actions are used, one does not need to care about which +legacy action parameters may (still...) be in effect. + +Note that not all modules necessarily support legacy action format. +Especially newer modules are recommended to NOT support it. + +Legacy Description +~~~~~~~~~~~~~~~~~~ + +Templates can be used with many actions. If used, the specified template +is used to generate the message content (instead of the default +template). To specify a template, write a semicolon after the action +value immediately followed by the template name. +Beware: templates MUST be defined BEFORE they are used. It is OK to +define some templates, then use them in selector lines, define more +templates and use use them in the following selector lines. But it is +NOT permitted to use a template in a selector line that is above its +definition. If you do this, the action will be ignored. + +**You can have multiple actions for a single selector** (or more +precisely a single filter of such a selector line). Each action must be +on its own line and the line must start with an ampersand ('&') +character and have no filters. An example would be + +:: + + *.=crit :omusrmsg:rger + & root + & /var/log/critmsgs + +These three lines send critical messages to the user rger and root and +also store them in /var/log/critmsgs. **Using multiple actions per +selector is** convenient and also **offers a performance benefit**. As +the filter needs to be evaluated only once, there is less computation +required to process the directive compared to the otherwise-equal config +directives below: + +:: + + *.=crit :omusrmsg:rger + *.=crit root + *.=crit /var/log/critmsgs + +Regular File +~~~~~~~~~~~~ + +Typically messages are logged to real files. The file usually is +specified by full pathname, beginning with a slash "/". Starting with +version 4.6.2 and 5.4.1 (previous v5 version do NOT support this) +relative file names can also be specified. To do so, these must begin +with a dot. For example, use "./file-in-current-dir.log" to specify a +file in the current directory. Please note that rsyslogd usually changes +its working directory to the root, so relative file names must be tested +with care (they were introduced primarily as a debugging vehicle, but +may have useful other applications as well). +You may prefix each entry with the minus "-'' sign to omit syncing the +file after every logging. Note that you might lose information if the +system crashes right behind a write attempt. Nevertheless this might +give you back some performance, especially if you run programs that use +logging in a very verbose manner. + +If your system is connected to a reliable UPS and you receive lots of +log data (e.g. firewall logs), it might be a very good idea to turn of +syncing by specifying the "-" in front of the file name. + +**The filename can be either static**\ (always the same) or **dynamic** +(different based on message received). The later is useful if you would +automatically split messages into different files based on some message +criteria. For example, dynamic file name selectors allow you to split +messages into different files based on the host that sent them. With +dynamic file names, everything is automatic and you do not need any +filters. + +It works via the template system. First, you define a template for the +file name. An example can be seen above in the description of template. +We will use the "DynFile" template defined there. Dynamic filenames are +indicated by specifying a questions mark "?" instead of a slash, +followed by the template name. Thus, the selector line for our dynamic +file name would look as follows: + + ``*.* ?DynFile`` + +That's all you need to do. Rsyslog will now automatically generate file +names for you and store the right messages into the right files. Please +note that the minus sign also works with dynamic file name selectors. +Thus, to avoid syncing, you may use + + ``*.* -?DynFile`` + +And of course you can use templates to specify the output format: + + ``*.* ?DynFile;MyTemplate`` + +**A word of caution:** rsyslog creates files as needed. So if a new host +is using your syslog server, rsyslog will automatically create a new +file for it. + +**Creating directories is also supported**. For example you can use the +hostname as directory and the program name as file name: + + ``$template DynFile,"/var/log/%HOSTNAME%/%programname%.log"`` + +Named Pipes +~~~~~~~~~~~ + +This version of rsyslogd(8) has support for logging output to named +pipes (fifos). A fifo or named pipe can be used as a destination for log +messages by prepending a pipe symbol ("\|'') to the name of the file. +This is handy for debugging. Note that the fifo must be created with the +mkfifo(1) command before rsyslogd(8) is started. + +Terminal and Console +~~~~~~~~~~~~~~~~~~~~ + +If the file you specified is a tty, special tty-handling is done, same +with /dev/console. + +Remote Machine +~~~~~~~~~~~~~~ + +Rsyslogd provides full remote logging, i.e. is able to send messages to +a remote host running rsyslogd(8) and to receive messages from remote +hosts. Using this feature you're able to control all syslog messages on +one host, if all other machines will log remotely to that. This tears +down administration needs. + +To forward messages to another host, prepend the hostname with the at +sign ("@"). A single at sign means that messages will be forwarded via +UDP protocol (the standard for syslog). If you prepend two at signs +("@@"), the messages will be transmitted via TCP. Please note that plain +TCP based syslog is not officially standardized, but most major syslogds +support it (e.g. syslog-ng or `WinSyslog <https://www.winsyslog.com/>`_). +The forwarding action indicator (at-sign) can be followed by one or more +options. If they are given, they must be immediately (without a space) +following the final at sign and be enclosed in parenthesis. The +individual options must be separated by commas. The following options +are right now defined: + +**z<number>** + +Enable zlib-compression for the message. The <number> is the compression +level. It can be 1 (lowest gain, lowest CPU overhead) to 9 (maximum +compression, highest CPU overhead). The level can also be 0, which means +"no compression". If given, the "z" option is ignored. So this does not +make an awful lot of sense. There is hardly a difference between level 1 +and 9 for typical syslog messages. You can expect a compression gain +between 0% and 30% for typical messages. Very chatty messages may +compress up to 50%, but this is seldom seen with typically traffic. +Please note that rsyslogd checks the compression gain. Messages with 60 +bytes or less will never be compressed. This is because compression gain +is pretty unlikely and we prefer to save CPU cycles. Messages over that +size are always compressed. However, it is checked if there is a gain in +compression and only if there is, the compressed message is transmitted. +Otherwise, the uncompressed messages is transmitted. This saves the +receiver CPU cycles for decompression. It also prevents small message to +actually become larger in compressed form. + +**Please note that when a TCP transport is used, compression will also +turn on syslog-transport-tls framing. See the "o" option for important +information on the implications.** + +Compressed messages are automatically detected and decompressed by the +receiver. There is nothing that needs to be configured on the receiver +side. + +**o** + +**This option is experimental. Use at your own risk and only if you know +why you need it! If in doubt, do NOT turn it on.** + +This option is only valid for plain TCP based transports. It selects a +different framing based on IETF internet draft syslog-transport-tls-06. +This framing offers some benefits over traditional LF-based framing. +However, the standardization effort is not yet complete. There may be +changes in upcoming versions of this standard. Rsyslog will be kept in +line with the standard. There is some chance that upcoming changes will +be incompatible to the current specification. In this case, all systems +using -transport-tls framing must be upgraded. There will be no effort +made to retain compatibility between different versions of rsyslog. The +primary reason for that is that it seems technically impossible to +provide compatibility between some of those changes. So you should take +this note very serious. It is not something we do not \*like\* to do +(and may change our mind if enough people beg...), it is something we +most probably \*can not\* do for technical reasons (aka: you can beg as +much as you like, it won't change anything...). + +The most important implication is that compressed syslog messages via +TCP must be considered with care. Unfortunately, it is technically +impossible to transfer compressed records over traditional syslog plain +tcp transports, so you are left with two evil choices... + + The hostname may be followed by a colon and the destination port. + +The following is an example selector line with forwarding: + +\*.\* @@(o,z9)192.168.0.1:1470 + +In this example, messages are forwarded via plain TCP with experimental +framing and maximum compression to the host 192.168.0.1 at port 1470. + +\*.\* @192.168.0.1 + +In the example above, messages are forwarded via UDP to the machine +192.168.0.1, the destination port defaults to 514. Messages will not be +compressed. + +Note that IPv6 addresses contain colons. So if an IPv6 address is +specified in the hostname part, rsyslogd could not detect where the IP +address ends and where the port starts. There is a syntax extension to +support this: put square brackets around the address (e.g. "[2001::1]"). +Square brackets also work with real host names and IPv4 addresses, too. + +A valid sample to send messages to the IPv6 host 2001::1 at port 515 is +as follows: + +\*.\* @[2001::1]:515 + +This works with TCP, too. + +**Note to sysklogd users:** sysklogd does **not** support RFC 3164 +format, which is the default forwarding template in rsyslog. As such, +you will experience duplicate hostnames if rsyslog is the sender and +sysklogd is the receiver. The fix is simple: you need to use a different +template. Use that one: + +$template sysklogd,"<%PRI%>%TIMESTAMP% %syslogtag%%msg%\\"" + \*.\* @192.168.0.1;sysklogd + +List of Users +~~~~~~~~~~~~~ + +Usually critical messages are also directed to "root'' on that machine. +You can specify a list of users that shall get the message by simply +writing ":omusrmsg: followed by the login name. For example, the send +messages to root, use ":omusrmsg:root". You may specify more than one +user by separating them with commas (",''). Do not repeat the +":omusrmsg:" prefix in this case. For example, to send data to users +root and rger, use ":omusrmsg:root,rger" (do not use +":omusrmsg:root,:omusrmsg:rger", this is invalid). If they're logged in +they get the message. + +Everyone logged on +~~~~~~~~~~~~~~~~~~ + +Emergency messages often go to all users currently online to notify them +that something strange is happening with the system. To specify this +wall(1)-feature use an asterisk as the user message +destination(":omusrmsg:\*''). + +Call Plugin +~~~~~~~~~~~ + +This is a generic way to call an output plugin. The plugin must support +this functionality. Actual parameters depend on the module, so see the +module's doc on what to supply. The general syntax is as follows: + +:modname:params;template + +Currently, the ommysql database output module supports this syntax (in +addition to the ">" syntax it traditionally supported). For ommysql, the +module name is "ommysql" and the params are the traditional ones. The +;template part is not module specific, it is generic rsyslog +functionality available to all modules. + +As an example, the ommysql module may be called as follows: + +:ommysql:dbhost,dbname,dbuser,dbpassword;dbtemplate + +For details, please see the "Database Table" section of this +documentation. + +Note: as of this writing, the ":modname:" part is hardcoded into the +module. So the name to use is not necessarily the name the module's +plugin file is called. + +Database Table +~~~~~~~~~~~~~~ + +This allows logging of the message to a database table. Currently, only +MySQL databases are supported. However, other database drivers will most +probably be developed as plugins. By default, a +`MonitorWare <https://www.mwagent.com/>`_-compatible schema is +required for this to work. You can create that schema with the +createDB.SQL file that came with the rsyslog package. You can also +use any other schema of your liking - you just need to define a proper +template and assign this template to the action. +The database writer is called by specifying a greater-then sign (">") +in front of the database connect information. Immediately after that +sign the database host name must be given, a comma, the database name, +another comma, the database user, a comma and then the user's password. +If a specific template is to be used, a semicolon followed by the +template name can follow the connect information. This is as follows: +>dbhost,dbname,dbuser,dbpassword;dbtemplate + +**Important: to use the database functionality, the MySQL output module +must be loaded in the config file** BEFORE the first database table +action is used. This is done by placing the + +:: + + $ModLoad ommysql + +directive some place above the first use of the database write (we +recommend doing at the beginning of the config file). + +Discard / Stop +~~~~~~~~~~~~~~ + +If the discard action is carried out, the received message is +immediately discarded. No further processing of it occurs. Discard has +primarily been added to filter out messages before carrying on any +further processing. For obvious reasons, the results of "discard" are +depending on where in the configuration file it is being used. Please +note that once a message has been discarded there is no way to retrieve +it in later configuration file lines. + +Discard can be highly effective if you want to filter out some annoying +messages that otherwise would fill your log files. To do that, place the +discard actions early in your log files. This often plays well with +property-based filters, giving you great freedom in specifying what you +do not want. + +Discard is just the word "stop" with no further parameters: + +stop + +For example, + +\*.\* stop + +discards everything (ok, you can achieve the same by not running rsyslogd +at all...). + +Note that in legacy configuration the tilde character "~" can also be +used instead of the word "stop". + +Output Channel +~~~~~~~~~~~~~~ + +Binds an output channel definition (see there for details) to this +action. Output channel actions must start with a $-sign, e.g. if you +would like to bind your output channel definition "mychannel" to the +action, use "$mychannel". Output channels support template definitions +like all all other actions. + +Shell Execute +~~~~~~~~~~~~~ + +**NOTE: This action is only supported for backwards compatibility. +For new configs, use** :doc:`omprog <modules/omprog>` **instead. +It provides a more solid +and secure solution with higher performance.** + +This executes a program in a subshell. The program is passed the +template-generated message as the only command line parameter. Rsyslog +waits until the program terminates and only then continues to run. + +^program-to-execute;template + +The program-to-execute can be any valid executable. It receives the +template string as a single parameter (argv[1]). + +**WARNING:** The Shell Execute action was added to serve an urgent need. +While it is considered reasonable save when used with some thinking, its +implications must be considered. The current implementation uses a +system() call to execute the command. This is not the best way to do it +(and will hopefully changed in further releases). Also, proper escaping +of special characters is done to prevent command injection. However, +attackers always find smart ways to circumvent escaping, so we can not +say if the escaping applied will really safe you from all hassles. +Lastly, rsyslog will wait until the shell command terminates. Thus, a +program error in it (e.g. an infinite loop) can actually disable +rsyslog. Even without that, during the programs run-time no messages are +processed by rsyslog. As the IP stacks buffers are quickly overflowed, +this bears an increased risk of message loss. You must be aware of these +implications. Even though they are severe, there are several cases where +the "shell execute" action is very useful. This is the reason why we +have included it in its current form. To mitigate its risks, always a) +test your program thoroughly, b) make sure its runtime is as short as +possible (if it requires a longer run-time, you might want to spawn your +own sub-shell asynchronously), c) apply proper firewalling so that only +known senders can send syslog messages to rsyslog. Point c) is +especially important: if rsyslog is accepting message from any hosts, +chances are much higher that an attacker might try to exploit the "shell +execute" action. + +Template Name +~~~~~~~~~~~~~ + +Every ACTION can be followed by a template name. If so, that template is +used for message formatting. If no name is given, a hard-coded default +template is used for the action. There can only be one template name for +each given action. The default template is specific to each action. For +a description of what a template is and what you can do with it, see the +:doc:`template<templates>` documentation. diff --git a/source/configuration/basic_structure.rst b/source/configuration/basic_structure.rst new file mode 100644 index 0000000..133da44 --- /dev/null +++ b/source/configuration/basic_structure.rst @@ -0,0 +1,233 @@ +Basic Structure +=============== + +This section describes how rsyslog configuration basically works. Think +of rsyslog as a big logging and event processing toolset. It can be considered +a framework with some basic processing that is fixed in the way data flows, +but is highly customizable in the details of this message flow. During +configuration, this customization is done by defining and customizing +the rsyslog objects. + +Quick overview of message flow and objects +------------------------------------------ +Messages enter rsyslog with the help of input modules. Then, they are +passed to a ruleset, where rules are conditionally applied. When a rule +matches, the message is transferred to an action, which then does +something to the message, e.g. writes it to a file, database or +forwards it to a remote host. + +Processing Principles +--------------------- + +- inputs submit received messages to rulesets + + * if the ruleset is not specifically bound, the default ruleset is used + +- by default, there is one ruleset (RSYSLOG_DefaultRuleset) + +- additional rulesets can be user-defined + +- each ruleset contains zero or more rules + + * while it is permitted to have zero rules inside a ruleset, + this obviously makes no sense + +- a rule consists of a filter and an action list + +- filters provide yes/no decisions and thus control-of-flow capability + +- if a filter "matches" (filter says "yes"), the corresponding + action list is executed. If it does not match, nothing special + happens + +- rules are evaluated in sequence from the first to the last rule + **inside** the given ruleset. No rules from unrelated rulesets are + ever executed. + +- all rules are **always** fully evaluated, no matter if a filter matches + or not (so we do **not** stop at the first match). If message processing + shall stop, the "discard" action (represented by the tilde character or the + stop command) must explicitly be executed. If discard is executed, + message processing immediately stops, without evaluating any further rules. + +- an action list contains one or many actions + +- inside an action list no further filters are possible + +- to have more than one action inside a list, the ampersand character + must be placed in the position of the filter, and this must immediately + follow the previous action + +- actions consist of the action call itself (e.g. ":omusrmsg:") as + well as all action-defining configuration statements ($Action... directives) + +- if legacy format is used (see below), $Action... directives **must** be + specified in front of the action they are intended to configure + +- some config directives automatically refer to their previous values + after being applied, others not. See the respective doc for details. Be + warned that this is currently not always properly documented. + +- in general, rsyslog v5 is heavily outdated and its native config language + is a pain. The rsyslog project strongly recommends using at least version 7, + where these problems are solved and configuration is much easier. + +- legacy configuration statements (those starting with $) do **not** affect + RainerScript objects (e.g. actions). + + +Configuration File +------------------ +Upon startup, rsyslog reads its configuration from the ``rsyslog.conf`` +file by default. This file may contain references to include other +config files. + +A different "root" configuration file can be specified via the ``-f <file>`` +rsyslogd command line option. This is usually done within some init +script or similar facility. + +Statement Types +--------------- +Rsyslog supports three different types of configuration statements +concurrently: + +- **sysklogd** - this is the plain old format, taught everywhere and + still pretty useful for simple use cases. Note that some + constructs are no longer supported because they are incompatible with + newer features. These are mentioned in the compatibility docs. +- **legacy rsyslog** - these are statements that begin with a dollar + sign. They set some (case-insensitive) configuration parameters and + modify e.g. the way actions operate. This is the only format supported + in pre-v6 versions of rsyslog. It is still fully supported in v6 and + above. Note that some plugins and features may still only be available + through legacy format (because plugins need to be explicitly upgraded + to use the new style format, and this hasn't happened to all plugins). +- **RainerScript** - the new style format. This is the best and most + precise format to be used for more complex cases. As with the legacy + format, RainerScript parameters are also case-insensitive. + The rest of this page assumes RainerScript based rsyslog.conf. + + +The rsyslog.conf files consists of statements. For old style (sysklogd & +legacy rsyslog), lines do matter. For new style (RainerScript) line +spacing is irrelevant. Most importantly, this means with new style +actions and all other objects can split across lines as users want to. + +Recommended use of Statement Types +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +In general it is recommended to use RainerScript type statements, as +these provide clean and easy to read control-of-flow as well as +no doubt about which parameters are active. They also have no +side-effects with include files, which can be a major obstacle with +legacy rsyslog statements. + +For very simple things sysklogd statement types are still suggested, +especially if the full config consists of such simple things. The +classical sample is writing to files (or forwarding) via priority. +In sysklogd, this looks like: + +:: + + mail.info /var/log/mail.log + mail.err @server.example.net + +This is hard to beat in simplicity, still being taught in courses +and a lot of people know this syntax. It is perfectly fine to use +these constructs even in newly written config files. + +**As a rule of thumb, RainerScript config statements should be used +when** + +- configuration parameters are required (e.g. the ``Action...`` + type of legacy statements) +- more elaborate control-of-flow is required (e.g. when multiple + actions must be nested under the same condition) + +It is usually **not** recommended to use rsyslog legacy config format +(those directives starting with a dollar sign). However, a few +settings and modules have not yet been converted to RainerScript. In +those cases, the legacy syntax must be used. + +Comments +-------- + +There are two types of comments: + +- **#-Comments** - start with a hash sign (#) and run to the end of the + line +- **C-style Comments** - start with /\* and end with \*/, just like in + the C programming language. They can be used to comment out multiple + lines at once. Comment nesting is not supported, but #-Comments can be + contained inside a C-style comment. + +Processing Order +---------------- + +Directives are processed from the top of rsyslog.conf to the bottom. +Order matters. For example, if you stop processing of a message, +obviously all statements after the stop statement are never evaluated. + +Flow Control Statements +~~~~~~~~~~~~~~~~~~~~~~~ + +Flow control is provided by: + +- :doc:`Control Structures <../rainerscript/control_structures>` + +- :doc:`Filter Conditions <filters>` + + +Data Manipulation Statements +~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +Data manipulation is achieved by **set**, **unset** and **reset** statements +which are :doc:`documented here in detail <../rainerscript/variable_property_types>`. + +Inputs +------ + +Every input requires an input module to be loaded and a listener defined +for it. Full details can be found inside the :doc:`rsyslog +modules <modules/index>` documentation. Once loaded, inputs +are defined via the **input()** object. + +Outputs +------- + +Outputs are also called "actions". A small set of actions is pre-loaded +(like the output file writer, which is used in almost every +rsyslog.conf), others must be loaded just like inputs. + +An action is invoked via the **action(type="type" ...)** object. Type is +mandatory and must contain the name of the plugin to be called (e.g. +"omfile" or "ommongodb"). Other parameters may be present. Their type and +use depends on the output plugin in question. + +Rulesets and Rules +------------------ + +Rulesets and rules form the basis of rsyslog processing. In short, a +rule is a way how rsyslog shall process a specific message. Usually, +there is a type of filter (if-statement) in front of the rule. Complex +nesting of rules is possible, much like in a programming language. + +Rulesets are containers for rules. A single ruleset can contain many +rules. In the programming language analogy, one may think of a ruleset +like being a program. A ruleset can be "bound" (assigned) to a specific +input. In the analogy, this means that when a message comes in via that +input, the "program" (ruleset) bound to it will be executed (but not any +other!). + +There is detailed documentation available for +:doc:`rsyslog rulesets <../concepts/multi_ruleset>`. + +For quick reference, rulesets are defined as follows: + +:: + + ruleset(name="rulesetname") { + action(type="omfile" file="/path/to/file") + action(type="..." ...) + /* and so on... */ + } diff --git a/source/configuration/conf_formats.rst b/source/configuration/conf_formats.rst new file mode 100644 index 0000000..c85af8b --- /dev/null +++ b/source/configuration/conf_formats.rst @@ -0,0 +1,94 @@ +Configuration Formats +===================== + +Rsyslog has evolved over several decades. For this reason it supports three +different configuration formats ("languages"): + +- |FmtBasicName| - previously known as the :doc:`sysklogd <sysklogd_format>` + format, this is the format best used to express basic things, such as where + the statement fits on a single line. It stems back to the original + syslog.conf format, in use now for several decades. + + The most common use case is matching on facility/severity and writing + matching messages to a log file. + +- |FmtAdvancedName| - previously known as the ``RainerScript`` format, this + format was first available in rsyslog v6 and is the current, best and most + precise format for non-trivial use cases where more than one line is needed. + + Prior to v7, there was a performance impact when using this format that + encouraged use of the |FmtBasicName| format for best results. Current + versions of rsyslog do not suffer from this (historical) performance impact. + + This new style format is specifically targeted towards more advanced use + cases like forwarding to remote hosts that might be partially offline. + +- |FmtObsoleteName| - previously known simply as the ``legacy`` format, this + format is exactly what its name implies: it is obsolete and should not + be used when writing new configurations. It was created in the early + days (up to rsyslog version 5) where we expected that rsyslog would extend + sysklogd just mildly. Consequently, it was primarily aimed at small + additions to the original sysklogd format. Practice has shown that it + was notoriously hard to use for more advanced use cases, and thus we + replaced it with the |FmtAdvancedName| format. + + In essence, everything that needs to be written on a single line that + starts with a dollar sign is legacy format. Users of this format are + encouraged to migrate to the |FmtBasicName| or |FmtAdvancedName| formats. + +Which Format should I Use? +~~~~~~~~~~~~~~~~~~~~~~~~~~ + +While rsyslog supports all three formats concurrently, you are **strongly** +encouraged to avoid using the |FmtObsoleteName| format. Instead, you should +use the |FmtBasicName| format for basic configurations and the |FmtAdvancedName| +format for anything else. + +While it is an older format, the |FmtBasicName| format is still suggested for +configurations that mostly consist of simple statements. The classic +example is writing to files (or forwarding) via priority. In |FmtBasicName| +format, this looks like: + +:: + + mail.info /var/log/mail.log + mail.err @@server.example.net + +This is hard to beat in simplicity, still being taught in courses +and a lot of people know this syntax. It is perfectly fine to use +these constructs even in newly written config files. Note that many +distributions use this format in their default rsyslog.conf, so you will +likely find it in existing configurations. + +**For anything more advanced, use** the |FmtAdvancedName| format. Advantages are: + +- fine control over rsyslog operations via advanced parameters +- easy to follow block structure +- easy to write +- safe for use with include files + +To continue with the above example, the |FmtAdvancedName| format is preferable +if you want to make sure that an offline remote destination will not slow down +local log file writing. In that case, forwarding is done via: + +:: + + mail.err action(type="omfwd" protocol="tcp" queue.type="linkedList") + +As can be seen by this example, the |FmtAdvancedName| format permits specifying +additional parameters to fine tune the behavior, whereas the |FmtBasicName| +format does not provide this level of control. + +**Do not use** |FmtObsoleteName| **format. It will make your life +miserable.** It is primarily supported in order to not break existing +configurations. + +Whatever you can do with the |FmtObsoleteName| format, you can also do +with the |FmtAdvancedName| format. The opposite is not true: Many newer features +cannot be turned on via the |FmtObsoleteName| format. The |FmtObsoleteName| +format is hard to understand and hard to get right. As you may inherit a rsyslog +configuration that makes use of it, this documentation gives you some clues +of what the obsolete statements do. For full details, obtain a +`v5 version of the rsyslog +documentation <http://www.rsyslog.com/doc/v5-stable/index.html>`_ (yes, this +format is dead since 2010!). diff --git a/source/configuration/config_param_types.rst b/source/configuration/config_param_types.rst new file mode 100644 index 0000000..36cc37c --- /dev/null +++ b/source/configuration/config_param_types.rst @@ -0,0 +1,48 @@ +Configuration Parameter Types +============================= +Configuration parameter values have different data types. +Unfortunately, the type currently must be guessed from the description +(consider contributing to the doc to help improve it). In general, the +following types are used: + +- **numbers** + + The traditional integer format. Numbers may include '.' and ',' + for readability. So you can for example specify either "1000" or + "1,000" with the same result. Please note that rsyslogd simply + *ignores* the punctuation. From it's point of view, "1,,0.0.,.,0" + also has the value 1000. + +- **sizes** + + Used for things like file size, main message queue sizes and the like. + These are integers, but support modifier after the number part. + For example, 1k means 1024. Supported are + k(ilo), m(ega), g(iga), t(era), p(eta) and e(xa). Lower case letters + refer to the traditional binary definition (e.g. 1m equals 1,048,576) + whereas upper case letters refer to their new 1000-based definition (e.g + 1M equals 1,000,000). + +- **complete line** + + A string consisting of multiple characters. This is relatively + seldom used and sometimes looks confusing (rsyslog v7+ has a much better + approach at these types of values). + +- **single word** + + This is used when only a single word can be provided. A "single + word" is a string without spaces in it. **No** quoting is necessary + nor permitted (the quotes would become part of the word). + +- **character** + + A single (printable) character. Must **not** be quoted. + +- **boolean** + + The traditional boolean type, specified as "on" (1) or "off" (0). + +Note that some other value types are occasionally used. However, the +majority of types is one of those listed above. The list is updated +as need arises and time permits. diff --git a/source/configuration/converting_to_new_format.rst b/source/configuration/converting_to_new_format.rst new file mode 100644 index 0000000..fcff061 --- /dev/null +++ b/source/configuration/converting_to_new_format.rst @@ -0,0 +1,196 @@ +Converting older formats to |FmtAdvancedName| +============================================= + +First of all, converting of older formats is not strictly necessary. All +formats can be mixed and matched and play well together. + +There are stil a number of reasons to convert older formats: + +* existing simple constructs need to be enhanced and become more complex +* aid future extensions +* ensure no side-effects accidentally occur +* unify rsyslog.conf language + +Do not overdo conversion +~~~~~~~~~~~~~~~~~~~~~~~~ + +Note: simple facility and severity based filters which trigger writing to +files can actually be very well expressd in |FmtBasicName|. So if you have +something like:: + + mail.info /var/log/maillog + +We suggest you leave it as-is without conversion. Equally, in our opinion it is +also fine to add new rules like the above. If you still want to convert, the +line may look as follows (completely in new format):: + + if prifilt("mail.info") then { + action(type="omfile" file="/var/log/maillog") + } + +More compact, this can also be written like:: + + if prifilt("mail.info") then action(type="omfile" file="/var/log/maillog") + +The older-selector-style filter is well-known, so this may also write it as:: + + mail.info action(type="omfile" file="/var/log/maillog") + +There are ample additional possibilities. We suggest to keep things consistent. + +Converting Module Load +~~~~~~~~~~~~~~~~~~~~~~ +This is very straight-forward. In |FmtObsoleteName| format we use:: + + $ModLoad module-name + +This is very simply converted to:: + + module(load="module-name") + +Sometimes modules provide global settings. In |FmtObsoleteName| format these are given in +individual lines **after** the \$ModLoad. In |FmtAdvancedName| format they are given inside +the module object. This makes it much clearer which module they belong to and +that they actually are global parameters (in contrast to per-action or per-listener +parameters). A typical example is `imtcp`:: + + $ModLoad imtcp + $InputTCPMaxSession 500 + +This is converted to:: + + module(load="imtcp" maxSessions="500") + +Note: in |FmtObsoleteName| format it is possible to provide global parameters more than once. +In this case it is unclear which one actually applies. For example:: + + $ModLoad imtcp + $InputTCPMaxSession 500 + ... + *.* /var/log/messages + ... + $InputTCPMaxSession 200 + +This is especially problematic if module-global parameters are used multiple times +in include files. + +In |FmtAdvancedName| format this is no longer possible. Module-global parameters can only +be applied once when the module is loaded. Any attempt to change them afterwards +results in an error message and will be ignored. The error messages will help you +find and fix multiple settings. Let us assume "200" is the setting actually intended +in above config snippet. So it would be converted to:: + + module(load="imtcp" maxSessions="200") + ... + *.* /var/log/messages + ... + + +Converting Actions +~~~~~~~~~~~~~~~~~~ +In general, you have lines like:: + + filter action + +where *filter* is any of the filters and *action* is ... the action to be +carried out. As could be seen above, the filter does **not** necessarily +need to be changed in order to convert the action. All filters also work +with all config formats. It often is best to keep existing filters, at +least while working on the conversion (do not change too many things at once). + +The following table lists traditional action syntax and how it can be +converted to new-style ``action()`` objects. The link will bring you to +detail documentation. In these detail documentations all parameters are given. +It is also specified which |FmtObsoleteName| directives map to |FmtAdvancedName| +properties. +This table is not conclusive but covers the most commonly used actions. + +.. csv-table:: + :header: "|FmtBasicName|", "|FmtAdvancedName|" + :widths: auto + :class: parameter-table + + "file path (`/var/log/...`)", "action(type="":doc:`omfile <modules/omfile>`"" file=""/var/log.../"" ...)" + "UDP forwarding (`@remote`)", "action(type="":doc:`omfwd <modules/omfwd>`"" target=""remote"" protocol=""udp"" ...)" + "TCP forwarding (`@@remote`)", "action(type="":doc:`omfwd <modules/omfwd>`"" target=""remote"" protocol=""tcp"" ...)" + "user notify (``:omusrmsg:user``)", "action(type="":doc:`omusrmsg <modules/omusrmsg>`"" users=""user"" ...)" + "module name (``:omxxx:..``)", "action(type="":doc:`omxxx <modules/idx_output>`"" ...)" + +Some concrete examples:: + + OLD: :hostname, contains, "remote-sender" @@central + NEW: :hostname, contains, "remote-sender" action(type="omfwd" target="central" protocol="tcp") + + OLD: if $msg contains "error" then @central + NEW: if $msg contains "error" then action(type="omfwd" target="central" protocol="udp") + + OLD: *.emerg :omusrmsg:* + NEW: *.emerg action(type="omusrmsg" users="*") + +**NOTE:** Some actions do not have a |FmtBasicName| format configuration line. They may +only be called via the ``action()`` syntax. Similarly, some very few actions, +mostly contributed, do not support ``action()`` syntax and thus can only be +configured via |FmtBasicName| and |FmtObsoleteName|. See module doc for details. + + +Action with Multiple Parameters +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +In many cases, actions have additional parameters, which also need to be converted. In +|FmtObsoleteName| format the action parameters are given before the actual action call. +To convert such constructs, you need to map all |FmtObsoleteName| parameters to |FmtAdvancedName| +ones. To look these up, you need to turn to three different documentation pages: + +* the :doc:`action object <actions>` itself +* the :doc:`output module <modules/idx_output>` that is called in the action (e.g. omfwd) +* the :doc:`queue documentation <../rainerscript/queue_parameters>` (if an action queue is used) + +To find the parameter in question, you can other do an on-page search via the browser on these +pages. Often it is very convenient to just use the +`rsyslog doc search engine <https://www.rsyslog.com/doc/master/search.html?q=>`_: +Type the |FmtObsoleteName| format statement into the search box. Most often, one of the first +search results is the matching object description doc page. + +Converting Action Chains +~~~~~~~~~~~~~~~~~~~~~~~~ + +Actions can be chained via the ampersand character ('``&``'). In |FmtAdvancedName| +format this has been replaced by blocks. For example:: + + *.error /var/log/errorlog + & @remote + +becomes:: + + *.error { + action(type="omfile" file="/var/log/errorlog") + action(type="omfwd" target="remote" protocol="udp") + } + +The latter is much easier to understand and less error-prone when extended. + +A common construct is to send messages to a remote host based on some message +content and then not further process it. This involves the ``stop`` statement +(or it's very old-time equivalent tilde ('``~``'). It may be specfied as such:: + + :msg, contains, "error" @remote + & ~ + +which is equavalent to:: + + :msg, contains, "error" @remote + & stop + +This format is often found in more modern distro's rsyslog.conf. It again is +fully equivalent to:: + + :msg, contains, "error" { + action(type="omfwd" target="remote" protocol="udp") + stop + } + +And, just to prove the point, this is also exactly the same like:: + + if $msg contains "error" then { + action(type="omfwd" target="remote" protocol="udp") + stop + } diff --git a/source/configuration/cryprov_gcry.rst b/source/configuration/cryprov_gcry.rst new file mode 100644 index 0000000..7dc32aa --- /dev/null +++ b/source/configuration/cryprov_gcry.rst @@ -0,0 +1,104 @@ +libgcrypt Log Crypto Provider (gcry) +==================================== + +**Crypto Provider Name:** gcry + +**Author:** Rainer Gerhards <rgerhards@adiscon.com> + +**Supported Since:** since 7.3.10 + +**Description**: + +Provides encryption support to rsyslog. + +**Configuration Parameters**: + +Crypto providers are loaded by omfile, when the provider is selected in +its "cry.providerName" parameter. Parameters for the provider are given +in the omfile action instance line. + +This provider creates an encryption information file with the same base +name but the extension ".encinfo" for each log file (both for fixed-name +files as well as dynafiles). Both files together form a set. So you need +to archive both in order to prove integrity. + +- **cry.algo** <Encryption Algorithm> + The algorithm (cipher) to be used for encryption. The default algorithm is "AES128". + Currently, the following Algorithms are supported: + + - 3DES + - CAST5 + - BLOWFISH + - AES128 + - AES192 + - AES256 + - TWOFISH + - TWOFISH128 + - ARCFOUR + - DES + - SERPENT128 + - SERPENT192 + - SERPENT256 + - RFC2268\_40 + - SEED + - CAMELLIA128 + - CAMELLIA192 + - CAMELLIA256 + + The actual availability of an algorithms depends on which ones are + compiled into libgcrypt. Note that some versions of libgcrypt simply + abort the process (rsyslogd in this case!) if a supported algorithm + is select but not available due to libgcrypt build settings. There is + nothing rsyslog can do against this. So in order to avoid production + downtime, always check carefully when you change the algorithm. + +- **cry.mode** <Algorithm Mode> + The encryption mode to be used. Default ist Cipher Block Chaining + (CBC). Note that not all encryption modes can be used together with + all algorithms. + Currently, the following modes are supported: + + - ECB + - CFB + - CBC + - STREAM + - OFB + - CTR + - AESWRAP + + +- **cry.key** <encryption key> + TESTING AID, NOT FOR PRODUCTION USE. This uses the KEY specified + inside rsyslog.conf. This is the actual key, and as such this mode is + highly insecure. However, it can be useful for initial testing steps. + This option may be removed in the future. + +- **cry.keyfile** <filename> + Reads the key from the specified file. The file must contain the + key, only, no headers or other meta information. Keyfiles can be + generated via the rscrytool utility. + +- **cry.keyprogram** <path to program> + If given, the key is provided by a so-called "key program". This + program is executed and must return the key (as well as some meta + information) via stdout. The core idea of key programs is that using + this interface the user can implement as complex (and secure) method + to obtain keys as desired, all without the need to make modifications + to rsyslog. + +**Caveats/Known Bugs:** + +- currently none known + +**Samples:** + +This encrypts a log file. Default parameters are used, they key is +provided via a keyfile. + +:: + + action(type="omfile" file="/var/log/somelog" cry.provider="gcry" + cry.keyfile="/secured/path/to/keyfile") + +Note that the keyfile can be generated via the rscrytool utility (see its +documentation for how to actually do that). diff --git a/source/configuration/droppriv.rst b/source/configuration/droppriv.rst new file mode 100644 index 0000000..8dc55a6 --- /dev/null +++ b/source/configuration/droppriv.rst @@ -0,0 +1,31 @@ +Dropping privileges in rsyslog +============================== + +**Available since**: 4.1.1 + +**Description**: + +Rsyslogd provides the ability to drop privileges by impersonating as +another user and/or group after startup. + +Please note that due to POSIX standards, rsyslogd always needs to start +up as root if there is a listener who must bind to a network port below +1024. For example, the UDP listener usually needs to listen to 514 and +therefore rsyslogd needs to start up as root. + +If you do not need this functionality, you can start rsyslog directly as +an ordinary user. That is probably the safest way of operations. +However, if a startup as root is required, you can use the +$PrivDropToGroup and $PrivDropToUser config directives to specify a +group and/or user that rsyslogd should drop to after initialization. +Once this happens, the daemon runs without high privileges (depending, +of course, on the permissions of the user account you specified). + +A special note for Docker and other container system users: user and +group names are usually not fully mirrored into containers. As such, +we strongly advise to use numerical IDs instead of user or group +names when configuring privilege drop. + +Privilege drop is configured via the +:doc:`global configuraton object<../rainerscript/global>` under the +"`privilege.`" set of parameters. diff --git a/source/configuration/dyn_stats.rst b/source/configuration/dyn_stats.rst new file mode 100644 index 0000000..b5d2ad9 --- /dev/null +++ b/source/configuration/dyn_stats.rst @@ -0,0 +1,106 @@ +Dynamic Stats +============= + +Rsyslog produces runtime-stats to allow user to study service health, performance, bottlenecks etc. Runtime-stats counters that Rsyslog components publish are statically defined. + +**Dynamic Stats** (called dyn-stats henceforth) component allows user to configure stats-namespaces (called stats-buckets) and increment counters within these buckets using Rainerscript function call. + +The metric-name in this case can be a message-property or a sub-string extracted from message etc. + +Dyn-stats configuration +^^^^^^^^^^^^^^^^^^^^^^^ + +Dyn-stats configuration involves a **two part setup**. + +dyn_stats(name="<bucket>"...) (object) +-------------------------------------- + +**Defines** the bucket(identified by the bucket-name) and allows user to set some properties that control behavior of the bucket. + +:: + + dyn_stats(name="msg_per_host") + +Parameters: + **name** <string literal, mandatory> : Name of the bucket. + + **resettable** <on|off, default: on> : Whether or not counters should be reset every time they are reported. This works independent of ``resetCounters`` config parameter in :doc:`modules/impstats`. + + **maxCardinality** <number, default: 2000> : Maximum number of unique counter-names to track. + + **unusedMetricLife** <number, default: 3600> : Interval between full purges (in seconds). This prevents unused counters from occupying resources forever. + + +A definition setting all the parameters looks like: + +:: + + dyn_stats(name="msg_per_host" resettable="on" maxCardinality="3000" unusedMetricLife="600") + + +dyn_inc("<bucket>", <expr>) (function) +-------------------------------------- + +**Increments** counter identified by value of variable in bucket identified by name. + +Parameters: + **name** <string literal, mandatory> : Name of the bucket + + **expr** <expression resulting in a string> : Name of counter (this name will be reported by impstats to identify the counter) + +A ``dyn_inc`` call looks like: + +:: + + set $.inc = dyn_inc("msg_per_host", $hostname); + + if ($.inc != 0) then { + .... + } + +``$.inc`` captures the error-code. It has value ``0`` when increment operation is successful and non-zero when it fails. It uses Rsyslog error-codes. + +Reporting +^^^^^^^^^ + +Legacy format: + +:: + + ... + global: origin=dynstats msg_per_host.ops_overflow=1 msg_per_host.new_metric_add=3 msg_per_host.no_metric=0 msg_per_host.metrics_purged=0 msg_per_host.ops_ignored=0 + ... + msg_per_host: origin=dynstats.bucket foo=2 bar=1 baz=1 + ... + +Json(variants with the same structure are used in other Json based formats such as ``cee`` and ``json-elasticsearch``) format: + +:: + + ... + { "name": "global", "origin": "dynstats", "values": { "msg_per_host.ops_overflow": 1, "msg_per_host.new_metric_add": 3, "msg_per_host.no_metric": 0, "msg_per_host.metrics_purged": 0, "msg_per_host.ops_ignored": 0 } } + ... + { "name": "msg_per_host", "origin": "dynstats.bucket", "values": { "foo": 2, "bar": 1, "baz": 1 } } + ... + +In this case counters are encapsulated inside an object hanging off top-level-key ``values``. + +Fields +------ + +**global: origin=dynstats**: + **ops_overflow**: Number of operations ignored because number-of-counters-tracked has hit configured max-cardinality. + + **new_metric_add**: Number of "new" metrics added (new counters created). + + **no_metric**: Counter-name given was invalid (length = 0). + + **metrics_purged**: Number of counters discarded at discard-cycle (controlled by **unusedMetricLife**). + + **ops_ignored**: Number of operations ignored due to potential performance overhead. Dyn-stats subsystem ignores operations to avoid performance-penalty if it can't get access to counter without delay(lock acquiring latency). + + **purge_triggered**: Indicates that a discard was performed (1 implies a discard-cycle run). + +**msg_per_host: origin=dynstats.bucket**: + **<metric_name>**: Value of counter identified by <metric-name>. + diff --git a/source/configuration/examples.rst b/source/configuration/examples.rst new file mode 100644 index 0000000..e035a0e --- /dev/null +++ b/source/configuration/examples.rst @@ -0,0 +1,214 @@ +Examples +-------- + +Below are example for templates and selector lines. I hope they are +self-explanatory. + +Templates +~~~~~~~~~ + +Please note that the samples are split across multiple lines. A template +MUST NOT actually be split across multiple lines. + +A template that resembles traditional syslogd file output: + $template TraditionalFormat,"%timegenerated% %HOSTNAME% + %syslogtag%%msg:::drop-last-lf%\\n" + +A template that tells you a little more about the message: + $template precise,"%syslogpriority%,%syslogfacility%,%timegenerated%,%HOSTNAME%, + %syslogtag%,%msg%\\n" + +A template for RFC 3164 format: + $template RFC3164fmt,"<%PRI%>%TIMESTAMP% %HOSTNAME% %syslogtag%%msg%" + +A template for the format traditionally used for user messages: + $template usermsg," XXXX%syslogtag%%msg%\\n\\r" + +And a template with the traditional wall-message format: + $template wallmsg,"\\r\\n\\7Message from syslogd@%HOSTNAME% at %timegenerated% + +A template that can be used for the database write (please note the SQL template option) + $template MySQLInsert,"insert iut, message, received at values + ('%iut%', '%msg:::UPPERCASE%', '%timegenerated:::date-mysql%') + into systemevents\\r\\n", SQL + +The following template emulates +`WinSyslog <http://www.winsyslog.com/en/>`_ format (it's an +`Adiscon <http://www.adiscon.com/>`_ format, you do not feel bad if +you don't know it ;)). It's interesting to see how it takes different +parts out of the date stamps. What happens is that the date stamp is +split into the actual date and time and the these two are combined with +just a comma in between them. + +:: + + $template WinSyslogFmt,"%HOSTNAME%,%timegenerated:1:10:date-rfc3339%, + %timegenerated:12:19:date-rfc3339%,%timegenerated:1:10:date-rfc3339%, + %timegenerated:12:19:date-rfc3339%,%syslogfacility%,%syslogpriority%, + %syslogtag%%msg%\\n" + +Selector lines +~~~~~~~~~~~~~~ + +:: + + # Store critical stuff in critical + # + *.=crit;kern.none /var/adm/critical + +This will store all messages with the priority crit in the file +/var/adm/critical, except for any kernel message. + +:: + + # Kernel messages are first, stored in the kernel + # file, critical messages and higher ones also go + # to another host and to the console. Messages to + # the host server.example.net are forwarded in RFC 3164 + # format (using the template defined above). + # + kern.* /var/adm/kernel + kern.crit @server.example.net;RFC3164fmt + kern.crit /dev/console + kern.info;kern.!err /var/adm/kernel-info + +The first rule direct any message that has the kernel facility to the +file /var/adm/kernel. + +The second statement directs all kernel messages of the priority crit +and higher to the remote host server.example.net. This is useful, because if the +host crashes and the disks get irreparable errors you might not be able +to read the stored messages. If they're on a remote host, too, you still +can try to find out the reason for the crash. + +The third rule directs these messages to the actual console, so the +person who works on the machine will get them, too. + +The fourth line tells rsyslogd to save all kernel messages that come +with priorities from info up to warning in the file /var/adm/kernel-info. +Everything from err and higher is excluded. + +:: + + # The tcp wrapper loggs with mail.info, we display + # all the connections on tty12 + # + mail.=info /dev/tty12 + +This directs all messages that uses mail.info (in source LOG\_MAIL \| +LOG\_INFO) to /dev/tty12, the 12th console. For example the tcpwrapper +tcpd(8) uses this as it's default. + +:: + + # Store all mail concerning stuff in a file + # + mail.\*;mail.!=info /var/adm/mail + +This pattern matches all messages that come with the mail facility, +except for the info priority. These will be stored in the file +/var/adm/mail. + +:: + + # Log all mail.info and news.info messages to info + # + mail,news.=info /var/adm/info + +This will extract all messages that come either with mail.info or with +news.info and store them in the file /var/adm/info. + +:: + + # Log info and notice messages to messages file + # + *.=info;*.=notice;\ + mail.none /var/log/messages + +This lets rsyslogd log all messages that come with either the info or +the notice facility into the file /var/log/messages, except for all +messages that use the mail facility. + +:: + + # Log info messages to messages file + # + *.=info;\ + mail,news.none /var/log/messages + +This statement causes rsyslogd to log all messages that come with the +info priority to the file /var/log/messages. But any message coming +either with the mail or the news facility will not be stored. + +:: + + # Emergency messages will be displayed to all users + # + *.=emerg :omusrmsg:* + +This rule tells rsyslogd to write all emergency messages to all +currently logged in users. + +:: + + # Messages of the priority alert will be directed + # to the operator + # + *.alert root,rgerhards + +This rule directs all messages with a priority of alert or higher to +the terminals of the operator, i.e. of the users "root'' and +"rgerhards'' if they're logged in. + +:: + + *.* @server.example.net + +This rule would redirect all messages to a remote host called +server.example.net. This is useful especially in a cluster of machines where all +syslog messages will be stored on only one machine. + +In the format shown above, UDP is used for transmitting the message. +The destination port is set to the default auf 514. Rsyslog is also +capable of using much more secure and reliable TCP sessions for message +forwarding. Also, the destination port can be specified. To select TCP, +simply add one additional @ in front of the host name (that is, @host is +UDP, @@host is TCP). For example: + +:: + + *.* @@server.example.net + +To specify the destination port on the remote machine, use a colon +followed by the port number after the machine name. The following +forwards to port 1514 on server.example.net: + +:: + + *.* @@server.example.net:1514 + +This syntax works both with TCP and UDP based syslog. However, you will +probably primarily need it for TCP, as there is no well-accepted port +for this transport (it is non-standard). For UDP, you can usually stick +with the default auf 514, but might want to modify it for security reasons. +If you would like to do that, it's quite easy: + +:: + + *.* @server.example.net:1514 + *.* >dbhost,dbname,dbuser,dbpassword;dbtemplate + +This rule writes all message to the database "dbname" hosted on +"dbhost". The login is done with user "dbuser" and password +"dbpassword". The actual table that is updated is specified within the +template (which contains the insert statement). The template is called +"dbtemplate" in this case. + +:: + + :msg,contains,"error" @server.example.net + +This rule forwards all messages that contain the word "error" in the msg +part to the server "errorServer". Forwarding is via UDP. Please note the +colon in fron + diff --git a/source/configuration/filters.rst b/source/configuration/filters.rst new file mode 100644 index 0000000..5357fad --- /dev/null +++ b/source/configuration/filters.rst @@ -0,0 +1,319 @@ +Filter Conditions +================= + +Rsyslog offers four different types "filter conditions": + +- "traditional" severity and facility based selectors +- property-based filters +- expression-based filters +- BSD-style blocks (not upward compatible) + +Selectors +--------- + +**Selectors are the traditional way of filtering syslog messages.** They +have been kept in rsyslog with their original syntax, because it is +well-known, highly effective and also needed for compatibility with +stock syslogd configuration files. If you just need to filter based on +priority and facility, you should do this with selector lines. They are +**not** second-class citizens in rsyslog and offer the simplest syntax +for this job. In versions of rsyslog prior to v7 there were significant +performance gains by using selector lines instead of the |FmtAdvancedName| +format. There is no longer any difference in performance between the two +formats. + +The selector field itself again consists of two parts, a facility and a +priority, separated by a period (".''). Both parts are case insensitive +and can also be specified as decimal numbers, but don't do that, you +have been warned. Both facilities and priorities are described in +syslog(3). The names mentioned below correspond to the similar +LOG\_-values in /usr/include/syslog.h. + +The facility is one of the following keywords: auth, authpriv, cron, +daemon, kern, lpr, mail, mark, news, security (same as auth), syslog, +user, uucp and local0 through local7. The keyword security should not be +used anymore and mark is only for internal use and therefore should not +be used in applications. Anyway, you may want to specify and redirect +these messages here. The facility specifies the subsystem that produced +the message, i.e. all mail programs log with the mail facility +(LOG\_MAIL) if they log using syslog. + +The priority is one of the following keywords, in ascending order: +debug, info, notice, warning, warn (same as warning), err, error (same +as err), crit, alert, emerg, panic (same as emerg). The keywords error, +warn and panic are deprecated and should not be used anymore. The +priority defines the severity of the message. + +The behavior of the original BSD syslogd is that all messages of the +specified priority and higher are logged according to the given action. +Rsyslogd behaves the same, but has some extensions. + +In addition to the above mentioned names the rsyslogd(8) understands +the following extensions: An asterisk ("\*'') stands for all facilities +or all priorities, depending on where it is used (before or after the +period). The keyword none stands for no priority of the given facility. +You can specify multiple facilities with the same priority pattern in +one statement using the comma (",'') operator. You may specify as much +facilities as you want. Remember that only the facility part from such a +statement is taken, a priority part would be skipped. + +Multiple selectors may be specified for a single action using the +semicolon (";'') separator. Remember that each selector in the selector +field is capable to overwrite the preceding ones. Using this behavior +you can exclude some priorities from the pattern. + +Rsyslogd has a syntax extension to the original BSD source, that makes +the use of selectors use more intuitively. You may precede every priority +with an equals +sign ("='') to specify only this single priority and not any of the +above. You may also (both is valid, too) precede the priority with an +exclamation mark ("!'') to ignore all that priorities, either exact this +one or this and any higher priority. If you use both extensions then the +exclamation mark must occur before the equals sign, just use it +intuitively. + +However, please note that there are some restrictions over the traditional +BSD syslog behaviour. These restrictions stem back to sysklogd, exist +probably since at least the 1990's and as such have always been in +rsyslog. + +Namely, in BSD syslogd you can craft a selector like this: + +\*.debug;local6.err + +The intent is to log all facilities at debug or higher, except for local6, +which should only log at err or higher. + +Unfortunately, local6.err will permit error severity and higher, but will +*not* exclude lower sevrity messages from facility local6. + +As an alternative, you can explicitely exclude all severities that you do +not want to match. For the above case, this selector is equivalent to the +BSD syslog selector: + +\*.debug;local6.!=info;local6.!=notice;local6.!=warn + +An easier approach is probably to do if ... then based matching in script. + +Property-Based Filters +---------------------- + +Property-based filters are unique to rsyslogd. They allow to filter on +any property, like HOSTNAME, syslogtag and msg. A list of all +currently-supported properties can be found in the :doc:`rsyslog properties +documentation <properties>`. With this filter, each property can be checked +against a specified value, using a specified compare operation. + +A property-based filter must start with a colon **in column 1**. This tells +rsyslogd that it is the new filter type. The colon must be followed by +the property name, a comma, the name of the compare operation to carry +out, another comma and then the value to compare against. This value +must be quoted. There can be spaces and tabs between the commas. +Property names and compare operations are case-sensitive, so "msg" +works, while "MSG" is an invalid property name. In brief, the syntax is +as follows: + +``:property, [!]compare-operation, "value"`` + +Compare-Operations +~~~~~~~~~~~~~~~~~~ + +The following **compare-operations** are currently supported: + +**contains** + Checks if the string provided in value is contained in the property. + There must be an exact match, wildcards are not supported. + +**isequal** + Compares the "value" string provided and the property contents. These + two values must be exactly equal to match. The difference to contains is + that contains searches for the value anywhere inside the property value, + whereas all characters must be identical for isequal. As such, isequal + is most useful for fields like syslogtag or FROMHOST, where you probably + know the exact contents. + +**startswith** + Checks if the value is found exactly at the beginning of the property + value. For example, if you search for "val" with + + ``:msg, startswith, "val"`` + + it will be a match if msg contains "values are in this message" but it + won't match if the msg contains "There are values in this message" (in + the later case, *"contains"* would match). Please note that "startswith" is + by far faster than regular expressions. So even once they are + implemented, it can make very much sense (performance-wise) to use + "startswith". + +**regex** + Compares the property against the provided POSIX BRE regular expression. + +**ereregex** + Compares the property against the provided POSIX ERE regular expression. + +You can use the bang-character (!) immediately in front of a +compare-operation, the outcome of this operation is negated. For +example, if msg contains "This is an informative message", the following +sample would not match: + +``:msg, contains, "error"`` + +but this one matches: + +``:msg, !contains, "error"`` + +Using negation can be useful if you would like to do some generic +processing but exclude some specific events. You can use the discard +action in conjunction with that. A sample would be: + +:: + + *.* /var/log/allmsgs-including-informational.log + :msg, contains, "informational" ~ + *.* /var/log/allmsgs-but-informational.log + +Do not overlook the tilde in line 2! In this sample, all messages +are written to the file allmsgs-including-informational.log. Then, all +messages containing the string "informational" are discarded. That means +the config file lines below the "discard line" (number 2 in our sample) +will not be applied to this message. Then, all remaining lines will also +be written to the file allmsgs-but-informational.log. + +Value Part +~~~~~~~~~~ + +**Value** is a quoted string. It supports some escape sequences: + +\\" - the quote character (e.g. "String with \\"Quotes\\"") + \\\\ - the backslash character (e.g. "C:\\\\tmp") + +Escape sequences always start with a backslash. Additional escape +sequences might be added in the future. Backslash characters **must** be +escaped. Any other sequence then those outlined above is invalid and may +lead to unpredictable results. + +Probably, "msg" is the most prominent use case of property based +filters. It is the actual message text. If you would like to filter +based on some message content (e.g. the presence of a specific code), +this can be done easily by: + +``:msg, contains, "ID-4711"`` + +This filter will match when the message contains the string "ID-4711". +Please note that the comparison is case-sensitive, so it would not match +if "id-4711" would be contained in the message. + +``:msg, regex, "fatal .* error"`` + +This filter uses a POSIX regular expression. It matches when the string +contains the words "fatal" and "error" with anything in between (e.g. +"fatal net error" and "fatal lib error" but not "fatal error" as two +spaces are required by the regular expression!). + +Getting property-based filters right can sometimes be challenging. In +order to help you do it with as minimal effort as possible, rsyslogd +spits out debug information for all property-based filters during their +evaluation. To enable this, run rsyslogd in foreground and specify the +"-d" option. + +Boolean operations inside property based filters (like 'message contains +"ID17" or message contains "ID18"') are currently not supported (except +for "not" as outlined above). Please note that while it is possible to +query facility and severity via property-based filters, it is far more +advisable to use classic selectors (see above) for those cases. + +Expression-Based Filters +------------------------ + +Expression based filters allow filtering on arbitrary complex +expressions, which can include boolean, arithmetic and string +operations. Expression filters will evolve into a full configuration +scripting language. Unfortunately, their syntax will slightly change +during that process. So if you use them now, you need to be prepared to +change your configuration files some time later. However, we try to +implement the scripting facility as soon as possible (also in respect to +stage work needed). So the window of exposure is probably not too long. + +Expression based filters are indicated by the keyword "if" in column 1 +of a new line. They have this format: + +:: + + if expr then action-part-of-selector-line + +"if" and "then" are fixed keywords that must be present. "expr" is a +(potentially quite complex) expression. So the :doc:`expression +documentation <../rainerscript/expressions>` for details. +"action-part-of-selector-line" is an action, just as you know it (e.g. +"/var/log/logfile" to write to that file). + +BSD-style Blocks +---------------- + +**Note:** rsyslog v7+ no longer supports BSD-style blocks +for technical reasons. So it is strongly recommended **not** to +use them. + +Rsyslogd supports BSD-style blocks inside rsyslog.conf. Each block of +lines is separated from the previous block by a program or hostname +specification. A block will only log messages corresponding to the most +recent program and hostname specifications given. Thus, a block which +selects ‘ppp’ as the program, directly followed by a block that selects +messages from the hostname ‘dialhost’, then the second block will only +log messages from the ppp program on dialhost. + +A program specification is a line beginning with ‘!prog’ and the +following blocks will be associated with calls to syslog from that +specific program. A program specification for ‘foo’ will also match any +message logged by the kernel with the prefix ‘foo: ’. Alternatively, a +program specification ‘-foo’ causes the following blocks to be applied +to messages from any program but the one specified. A hostname +specification of the form ‘+hostname’ and the following blocks will be +applied to messages received from the specified hostname. Alternatively, +a hostname specification ‘-hostname’ causes the following blocks to be +applied to messages from any host but the one specified. If the hostname +is given as ‘@’, the local hostname will be used. (NOT YET IMPLEMENTED) +A program or hostname specification may be reset by giving the program +or hostname as ‘\*’. + +Please note that the "#!prog", "#+hostname" and "#-hostname" syntax +available in BSD syslogd is not supported by rsyslogd. By default, no +hostname or program is set. + +Examples +-------- + +:: + + *.* /var/log/file1 # the traditional way + if $msg contains 'error' then /var/log/errlog # the expression-based way + +Right now, you need to specify numerical values if you would like to +check for facilities and severity. These can be found in :rfc:`5424`. +If you don't like that, +you can of course also use the textual property - just be sure to use +the right one. As expression support is enhanced, this will change. For +example, if you would like to filter on message that have facility +local0, start with "DEVNAME" and have either "error1" or "error0" in +their message content, you could use the following filter: + +:: + + if $syslogfacility-text == 'local0' and $msg startswith 'DEVNAME' and ($msg contains 'error1' or $msg contains 'error0') then /var/log/somelog + +Please note that the above must all be on one line! And if you would +like to store all messages except those that contain "error1" or +"error0", you just need to add a "not": + +:: + + if $syslogfacility-text == 'local0' and $msg startswith 'DEVNAME' and not ($msg contains 'error1' or $msg contains 'error0') then /var/log/somelog + +If you would like to do case-insensitive comparisons, use "contains\_i" +instead of "contains" and "startswith\_i" instead of "startswith". +Note that regular expressions are currently NOT supported in +expression-based filters. These will be added later when function +support is added to the expression engine (the reason is that regular +expressions will be a separate loadable module, which requires some more +prerequisites before it can be implemented). + diff --git a/source/configuration/global/index.rst b/source/configuration/global/index.rst new file mode 100644 index 0000000..2e6b840 --- /dev/null +++ b/source/configuration/global/index.rst @@ -0,0 +1,163 @@ +Legacy Global Configuration Statements +====================================== +Global configuration statements, as their name implies, usually affect +some global features. However, some also affect main queues, which +are "global" to a ruleset. + +True Global Directives +---------------------- + +.. toctree:: + :glob: + + options/rsconf1_abortonuncleanconfig + options/rsconf1_debugprintcfsyslinehandlerlist + options/rsconf1_debugprintmodulelist + options/rsconf1_debugprinttemplatelist + options/rsconf1_failonchownfailure + options/rsconf1_generateconfiggraph + options/rsconf1_includeconfig + options/rsconf1_mainmsgqueuesize + options/rsconf1_maxopenfiles + options/rsconf1_moddir + options/rsconf1_modload + options/rsconf1_umask + options/rsconf1_resetconfigvariables + +- **$MaxMessageSize** <size\_nbr>, default 8k - allows to specify + maximum supported message size (both for sending and receiving). The + default should be sufficient for almost all cases. Do not set this + below 1k, as it would cause interoperability problems with other + syslog implementations. + + **Important:** In order for this directive to work correctly, + it **must** be placed right at the top of ``rsyslog.conf`` + (before any input is defined). + + Change the setting to e.g. 32768 if you would like to support large + message sizes for IHE (32k is the current maximum needed for IHE). I + was initially tempted to set the default to 32k, but there is a some + memory footprint with the current implementation in rsyslog. + If you intend to receive Windows Event Log data (e.g. via + `EventReporter <http://www.eventreporter.com/>`_), you might want to + increase this number to an even higher value, as event log messages + can be very lengthy ("$MaxMessageSize 64k" is not a bad idea). Note: + testing showed that 4k seems to be the typical maximum for **UDP** + based syslog. This is an IP stack restriction. Not always ... but + very often. If you go beyond that value, be sure to test that + rsyslogd actually does what you think it should do ;) It is highly + suggested to use a TCP based transport instead of UDP (plain TCP + syslog, RELP). This resolves the UDP stack size restrictions. + Note that 2k, is the smallest size that must be + supported in order to be compliant to the upcoming new syslog RFC + series. +- **$LocalHostName** [name] - this directive permits to overwrite the + system hostname with the one specified in the directive. If the + directive is given multiple times, all but the last one will be + ignored. Please note that startup error messages may be issued with + the real hostname. This is by design and not a bug (but one may argue + if the design should be changed ;)). Available since 4.7.4+, 5.7.3+, + 6.1.3+. +- **$LogRSyslogStatusMessages** [**on**/off] - If set to on (the + default), rsyslog emits message on startup and shutdown as well as + when it is HUPed. This information might be needed by some log + analyzers. If set to off, no such status messages are logged, what + may be useful for other scenarios. [available since 4.7.0 and 5.3.0] +- **$DefaultRuleset** [name] - changes the default ruleset for unbound + inputs to the provided *name* (the default default ruleset is named + "RSYSLOG\_DefaultRuleset"). It is advised to also read our paper on + :doc:`using multiple rule sets in rsyslog <../../concepts/multi_ruleset>`. +- **$DefaultNetstreamDriver** <drivername>, the default + :doc:`network stream driver <../../concepts/netstrm_drvr>` to use. + Defaults to ptcp. +- **$DefaultNetstreamDriverCAFile** </path/to/cafile.pem> +- **$DefaultNetstreamDriverCertFile** </path/to/certfile.pem> +- **$DefaultNetstreamDriverKeyFile** </path/to/keyfile.pem> +- **$NetstreamDriverCaExtraFiles** </path/to/extracafile.pem> - This + directive allows to configure multiple additional extra CA files. + This is intended for SSL certificate chains to work appropriately, + as the different CA files in the chain need to be specified. + It must be remarked that this directive only works with the OpenSSL driver. +- **$RepeatedMsgContainsOriginalMsg** [on/**off**] - "last message + repeated n times" messages, if generated, have a different format + that contains the message that is being repeated. Note that only the + first "n" characters are included, with n to be at least 80 + characters, most probably more (this may change from version to + version, thus no specific limit is given). The bottom line is that n + is large enough to get a good idea which message was repeated but it + is not necessarily large enough for the whole message. (Introduced + with 4.1.5). Once set, it affects all following actions. +- **$OptimizeForUniprocessor** - This directive is no longer supported. + While present in versions prior to 8.32.0, the directive had no effect + for many years. Attempts to use the directive now results in a warning. +- **$PreserveFQDN** [on/**off**) - if set to off (legacy default to remain + compatible to sysklogd), the domain part from a name that is within + the same domain as the receiving system is stripped. If set to on, + full names are always used. +- **$WorkDirectory** <name> (directory for spool and other work files. Do + **not** use trailing slashes) +- `$PrivDropToGroup <droppriv.html>`_ +- `$PrivDropToGroupID <droppriv.html>`_ +- `$PrivDropToUser <droppriv.html>`_ +- `$PrivDropToUserID <droppriv.html>`_ +- **$Sleep** <seconds> - puts the rsyslog main thread to sleep for the + specified number of seconds immediately when the directive is + encountered. You should have a good reason for using this directive! +- **$LocalHostIPIF** <interface name> - (available since 5.9.6) - if + provided, the IP of the specified interface (e.g. "eth0") shall be + used as fromhost-ip for local-originating messages. If this + directive is not given OR the interface cannot be found (or has no IP + address), the default of "127.0.0.1" is used. Note that this + directive can be given only once. Trying to reset will result in an + error message and the new value will be ignored. Please note that + modules must have support for obtaining the local IP address set via + this directive. While this is the case for rsyslog-provided modules, + it may not always be the case for contributed plugins. + **Important:** This directive shall be placed **right at the top of + rsyslog.conf**. Otherwise, if error messages are triggered before + this directive is processed, rsyslog will fix the local host IP to + "127.0.0.1", what than can not be reset. +- **$ErrorMessagesToStderr** [**on**\ \|off] - direct rsyslogd error + message to stderr (in addition to other targets) +- **$SpaceLFOnReceive** [on/**off**] - instructs rsyslogd to replace LF + with spaces during message reception (sysklogd compatibility aid). + This is applied at the beginning of the parser stage and cannot + be overridden (neither at the input nor parser level). Consequently, + it affects all inputs and parsers. + +main queue specific Directives +------------------------------ +Note that these directives modify ruleset main message queues. +This includes the default ruleset's main message queue, the one +that is always present. To do this, specify directives outside of +a ruleset definition. + +To understand queue parameters, read +:doc:`queues in rsyslog <../../concepts/queues>`. + +- **$MainMsgQueueCheckpointInterval** <number> +- **$MainMsgQueueDequeueBatchSize** <number> [default 32] +- **$MainMsgQueueDequeueSlowdown** <number> [number is timeout in + *micro*\ seconds (1000000us is 1sec!), default 0 (no delay). Simple + rate-limiting!] +- **$MainMsgQueueDiscardMark** <number> [default 98% of queue size] +- **$MainMsgQueueDiscardSeverity** <severity> [either a textual or + numerical severity! default 4 (warning)] +- **$MainMsgQueueFileName** <name> +- **$MainMsgQueueHighWaterMark** <number> [default 90% of queue size] +- **$MainMsgQueueImmediateShutdown** [on/**off**] +- **$MainMsgQueueLowWaterMark** <number> [default 70% of queue size] +- **$MainMsgQueueMaxFileSize** <size\_nbr>, default 1m +- **$MainMsgQueueTimeoutActionCompletion** <number> [number is timeout in + ms (1000ms is 1sec!), default 1000, 0 means immediate!] +- **$MainMsgQueueTimeoutEnqueue** <number> [number is timeout in ms (1000ms + is 1sec!), default 2000, 0 means discard immediately] +- **$MainMsgQueueTimeoutShutdown** <number> [number is timeout in ms + (1000ms is 1sec!), default 0 (indefinite)] +- **$MainMsgQueueWorkerTimeoutThreadShutdown** <number> [number is timeout + in ms (1000ms is 1sec!), default 60000 (1 minute)] +- **$MainMsgQueueType** [**FixedArray**/LinkedList/Direct/Disk] +- **$MainMsgQueueSaveOnShutdown** [on/**off**] +- **$MainMsgQueueWorkerThreads** <number>, num worker threads, default 2, + recommended 1 +- **$MainMsgQueueWorkerThreadMinumumMessages** <number>, default queue size/number of workers diff --git a/source/configuration/global/options/rsconf1_abortonuncleanconfig.rst b/source/configuration/global/options/rsconf1_abortonuncleanconfig.rst new file mode 100644 index 0000000..f1a7fb3 --- /dev/null +++ b/source/configuration/global/options/rsconf1_abortonuncleanconfig.rst @@ -0,0 +1,40 @@ +`rsyslog.conf configuration parameter <rsyslog_conf_global.html>`_ + +$AbortOnUncleanConfig +---------------------- + +**Type:** global configuration parameter + +**Parameter Values:** boolean (on/off, yes/no) + +**Available since:** 5.3.1+ + +**Default:** off + +**Description:** + +This parameter permits to prevent rsyslog from running when the +configuration file is not clean. "Not Clean" means there are errors or +some other annoyances that rsyslogd reports on startup. This is a +user-requested feature to have a strict startup mode. Note that with the +current code base it is not always possible to differentiate between an +real error and a warning-like condition. As such, the startup will also +prevented if warnings are present. I consider this a good thing in being +"strict", but I admit there also currently is no other way of doing it. + +It is recommended to use the new config style. The equivalent of this +parameter in the new style is ``global(abortOnUncleanConfig="")``. + +**Caveats:** + +Note that the consequences of a failed rsyslogd startup can be much more +serious than a startup with only partial configuration. For example, log +data may be lost or systems that depend on the log server in question +will not be able to send logs, what in the ultimate result could result +in a system hang on those systems. Also, the local system may hang when +the local log socket has become full and is not read. There exist many +such scenarios. As such, it is strongly recommended not to turn on this +parameter. + +[`rsyslog site <http://www.rsyslog.com/>`_\ ] + diff --git a/source/configuration/global/options/rsconf1_debugprintcfsyslinehandlerlist.rst b/source/configuration/global/options/rsconf1_debugprintcfsyslinehandlerlist.rst new file mode 100644 index 0000000..70ceb4c --- /dev/null +++ b/source/configuration/global/options/rsconf1_debugprintcfsyslinehandlerlist.rst @@ -0,0 +1,13 @@ +$DebugPrintCFSyslineHandlerList +------------------------------- + +**Type:** global configuration parameter + +**Default:** on + +**Description:** + +Specifies whether or not the configuration file sysline handler list +should be written to the debug log. Possible values: on/off. Default is +on. Does not affect operation if debugging is disabled. + diff --git a/source/configuration/global/options/rsconf1_debugprintmodulelist.rst b/source/configuration/global/options/rsconf1_debugprintmodulelist.rst new file mode 100644 index 0000000..8ddfa79 --- /dev/null +++ b/source/configuration/global/options/rsconf1_debugprintmodulelist.rst @@ -0,0 +1,12 @@ +$DebugPrintModuleList +--------------------- + +**Type:** global configuration parameter + +**Default:** on + +**Description:** + +Specifies whether or not the module list should be written to the debug +log. Possible values: on/off. Default is on. Does not affect operation +if debugging is disabled. diff --git a/source/configuration/global/options/rsconf1_debugprinttemplatelist.rst b/source/configuration/global/options/rsconf1_debugprinttemplatelist.rst new file mode 100644 index 0000000..d67a05e --- /dev/null +++ b/source/configuration/global/options/rsconf1_debugprinttemplatelist.rst @@ -0,0 +1,12 @@ +$DebugPrintTemplateList +----------------------- + +**Type:** global configuration parameter + +**Default:** on + +**Description:** + +Specifies whether or not the template list should be written to the +debug log. Possible values: on/off. Default is on. Does not affect +operation if debugging is disabled.. diff --git a/source/configuration/global/options/rsconf1_failonchownfailure.rst b/source/configuration/global/options/rsconf1_failonchownfailure.rst new file mode 100644 index 0000000..01d6c5a --- /dev/null +++ b/source/configuration/global/options/rsconf1_failonchownfailure.rst @@ -0,0 +1,21 @@ +$FailOnChownFailure +------------------- + +**Type:** global configuration parameter + +**Default:** on + +**Description:** + +This option modifies behaviour of dynaFile creation. If different owners +or groups are specified for new files or directories and rsyslogd fails +to set these new owners or groups, it will log an error and NOT write to +the file in question if that option is set to "on". If it is set to +"off", the error will be ignored and processing continues. Keep in mind, +that the files in this case may be (in)accessible by people who should +not have permission. The default is "on". + +**Sample:** + +``$FailOnChownFailure off`` + diff --git a/source/configuration/global/options/rsconf1_generateconfiggraph.rst b/source/configuration/global/options/rsconf1_generateconfiggraph.rst new file mode 100644 index 0000000..4c70832 --- /dev/null +++ b/source/configuration/global/options/rsconf1_generateconfiggraph.rst @@ -0,0 +1,148 @@ +$GenerateConfigGraph +-------------------- + +**Type:** global configuration parameter + +**Default:** + +**Available Since:** 4.3.1 **CURRENTLY NOT AVAILABLE** + +**Description:** + +**This parameter is currently not supported. We had to disable it when +we improved the rule engine. It is considerable effort to re-enable it. +On the other hand, we are about to add a new config system, which will +make yet another config graph method necessary. As such we have decided +to currently disable this functionality and re-introduce it when the new +config system has been instantiated.** + +This parameter permits to create (hopefully) good-looking visualizations +of rsyslogd's configuration. It does not affect rsyslog operation. If +the parameter is specified multiple times, all but the last are ignored. +If it is specified, a graph is created. This happens both during a +regular startup as well a config check run. It is recommended to include +this parameter only for documentation purposes and remove it from a +production configuration. + +The graph is not drawn by rsyslog itself. Instead, it uses the great +open source tool `Graphviz <http://www.graphviz.org>`_ to do the actual +drawing. This has at least two advantages: + +- the graph drawing support code in rsyslog is extremely slim and + without overhead +- the user may change or further annotate the generated file, thus + potentially improving his documentation + +The drawback, of course, is that you need to run Graphviz once you have +generated the control file with rsyslog. Fortunately, the process to do +so is rather easy: + +#. add "$GenerateConfigGraph /path/to/file.dot" to rsyslog.conf (from + now on, I will call the file just file.dot). Optionally, add + "$ActionName" statement **in front of** those actions that you like + to use friendly names with. If you do this, keep the names short. +#. run rsyslog at least once (either in regular or configuration check + mode) +#. remember to remove the $GenerateConfigGraph parameter when you no + longer need it (or comment it out) +#. change your working directory to where you place the dot file +#. if you would like to edit the rsyslog-generated file, now is the time + to do so +#. do "dot -Tpng file.dot > file.png" +#. remember that you can use "convert -resize 50% file.png resized.png" + if dot's output is too large (likely) or too small. Resizing can be + especially useful if you intend to get a rough overview over your + configuration. + +After completing these steps, you should have a nice graph of your +configuration. Details are missing, but that is exactly the point. At +the start of the graph is always (at least in this version, could be +improved) a node called "inputs" in a triple hexagon shape. This +represents all inputs active in the system (assuming you have defined +some, what the current version does not check). Next comes the main +queue. It is given in a hexagon shape. That shape indicates that a queue +is present and used to de-couple the inbound from the outbound part of +the graph. In technical terms, here is a threading boundary. Action with +"real" queues (other than in direct mode) also utilize this shape. For +actions, notice that a "hexagon action" creates a deep copy of the +message. As such, a "discard hexagon action" actually does nothing, +because it duplicates the message and then discards **the duplicate**. +At the end of the diagram, you always see a "discard" action. This +indicates that rsyslog discards messages which have been run through all +available rules. + +Edges are labeled with information about when they are taken. For +filters, the type of filter, but not any specifics, are given. It is +also indicated if no filter is applied in the configuration file (by +using a "\*.\*" selector). Edges without labels are unconditionally +taken. The actions themselves are labeled with the name of the output +module that handles them. If provided, the name given via "ActionName" +is used instead. No further details are provided. + +If there is anything in red, this should draw your attention. In this +case, rsyslogd has detected something that does not look quite right. A +typical example is a discard action which is followed by some other +actions in an action unit. Even though something may be red, it can be +valid - rsyslogd's graph generator does not yet check each and every +specialty, so the configuration may just cover a very uncommon case. + +Now let's look at some examples. The graph below was generated on a +fairly standard Fedora rsyslog.conf file. It had only the usually +commented-out last forwarding action activated: + +.. figure:: rsyslog_confgraph_std.png + :align: center + :alt: rsyslog configuration graph for a default fedora rsyslog.conf + + rsyslog configuration graph for a default fedora rsyslog.conf + +This is the typical structure for a simple rsyslog configuration. There +are a couple of actions, each guarded by a filter. Messages run from top +to bottom and control branches whenever a filter evaluates to true. As +there is no discard action, all messages will run through all filters +and discarded in the system default discard action right after all +configured actions. + +A more complex example can be seen in the next graph. This is a +configuration I created for testing the graph-creation features, so it +contains a little bit of everything. However, real-world configurations +can look quite complex, too (and I wouldn't say this one is very +complex): + +.. figure:: rsyslog_confgraph_complex.png + :align: center + :alt: + +Here, we have a user-defined discard action. You can immediately see +this because processing branches after the first "builtin-file" action. +Those messages where the filter evaluates to true for will never run +through the left-hand action branch. However, there is also a +configuration error present: there are two more actions (now shown red) +after the discard action. As the message is discarded, these will never +be executed. Note that the discard branch contains no further filters. +This is because these actions are all part of the same action unit, +which is guarded only by an entry filter. The same is present a bit +further down at the node labeled "write\_system\_log\_2". This note has +one more special feature, that is label was set via "ActionName", thus +is does not have standard form (the same happened to the node named +"Forward" right at the top of the diagram. Inside this diagram, the +"Forward" node is executed asynchronously on its own queue. All others +are executed synchronously. + +Configuration graphs are useful for documenting a setup, but are also a +great `troubleshooting <troubleshoot.html>`_ resource. It is important +to remember that **these graphs are generated from rsyslogd's in-memory +action processing structures**. You can not get closer to understanding +on how rsyslog interpreted its configuration files. So if the graph does +not look what you intended to do, there is probably something wrong in +rsyslog.conf. + +If something is not working as expected, but you do not spot the error +immediately, I recommend to generate a graph and zoom it so that you see +all of it in one great picture. You may not be able to read anything, +but the structure should look good to you and so you can zoom into those +areas that draw your attention. + +**Sample:** + +``$DirOwner /path/to/graphfile-file.dot`` diff --git a/source/configuration/global/options/rsconf1_includeconfig.rst b/source/configuration/global/options/rsconf1_includeconfig.rst new file mode 100644 index 0000000..a177324 --- /dev/null +++ b/source/configuration/global/options/rsconf1_includeconfig.rst @@ -0,0 +1,74 @@ +$IncludeConfig +-------------- + +.. warning:: + + This legacy directive has been superseeded by the rsyslog + :doc:`include() <../../../rainerscript/include>` + configuration object. + While it is save to use the legacy statement, we highly + recommend to use it's modern counterpart. Among others, + the `include()` object provides enhanced functionality. + +**Type:** global configuration parameter + +**Default:** + +**Description:** + +This parameter allows to include other files into the main configuration +file. As soon as an IncludeConfig parameter is found, the contents of +the new file is processed. IncludeConfigs can be nested. Please note +that from a logical point of view the files are merged. Thus, if the +include modifies some parameters (e.g. $DynaFileCacheSize), these new +parameters are in place for the "calling" configuration file when the +include is completed. To avoid any side effects, do a +$ResetConfigVariables after the $IncludeConfig. It may also be a good +idea to do a $ResetConfigVariables right at the start of the include, so +that the module knows exactly what it does. Of course, one might +specifically NOT do this to inherit parameters from the main file. As +always, use it as it best fits... + +Note: if multiple files are included, they are processed in ascending +sort order of the file name. We use the "glob()" C library function +for obtaining the sorted list. On most platforms, especially Linux, +this means the sort order is the same as for bash. + +If all regular files in the /etc/rsyslog.d directory are included, then +files starting with "." are ignored - so you can use them to place +comments into the dir (e.g. "/etc/rsyslog.d/.mycomment" will be +ignored). `Michael Biebl had the idea to this +functionality <http://sourceforge.net/tracker/index.php?func=detail&aid=1764088&group_id=123448&atid=696555>`_. +Let me quote him: + + Say you can add an option + ``$IncludeConfig /etc/rsyslog.d/`` + (which probably would make a good default) + to ``/etc/rsyslog.conf``, which would then merge and include all + ``*.conf`` files + in ``/etc/rsyslog.d/``. + This way, a distribution can modify its packages easily to drop a + simple + config file into this directory upon installation. + As an example, the network-manager package could install a simple + config + file ``/etc/rsyslog.d/network-manager.conf`` which would contain. + ``:programname, contains, "NetworkManager" -/var/log/NetworkManager.log`` + Upon uninstallation, the file could be easily removed again. This + approach would be much cleaner and less error prone, than having to munge + around with the ``/etc/rsyslog.conf`` file directly. + +**Sample:** + +``$IncludeConfig /etc/some-included-file.conf`` + +Directories can also be included. To do so, the name must end on a +slash: + +``$IncludeConfig /etc/rsyslog.d/`` + +**And finally, only specific files matching a wildcard my be included +from a directory:** + +``$IncludeConfig /etc/rsyslog.d/*.conf`` + diff --git a/source/configuration/global/options/rsconf1_mainmsgqueuesize.rst b/source/configuration/global/options/rsconf1_mainmsgqueuesize.rst new file mode 100644 index 0000000..8b74b59 --- /dev/null +++ b/source/configuration/global/options/rsconf1_mainmsgqueuesize.rst @@ -0,0 +1,34 @@ +$MainMsgQueueSize +----------------- + +**Type:** global configuration parameter + +**Default:** 50000 (v8.30.0) - may change + +**Description:** + +This allows to specify the maximum size of the message queue. This +parameter is only available when rsyslogd has been compiled with +multithreading support. In this mode, receiver and output modules are +de-coupled via an in-memory queue. This queue buffers messages when the +output modules are not capable to process them as fast as they are +received. Once the queue size is exhausted, messages will be dropped. +The slower the output (e.g. MySQL), the larger the queue should be. +Buffer space for the actual queue entries is allocated on an as-needed +basis. Please keep in mind that a very large queue may exhaust available +system memory and swap space. Keep this in mind when configuring the max +size. The actual size of a message depends largely on its content and +the originator. As a rule of thumb, typically messages should not take +up more then roughly 1k (this is the memory structure, not what you see +in a network dump!). For typical linux messages, 512 bytes should be a +good bet. Please also note that there is a minimal amount of memory +taken for each queue entry, no matter if it is used or not. This is one +pointer value, so on 32bit systems, it should typically be 4 bytes and +on 64bit systems it should typically be 8 bytes. For example, the +default queue size of 10,000 entries needs roughly 40k fixed overhead on +a 32 bit system. + +**Sample:** + +``$MainMsgQueueSize 100000 # 100,000 may be a value to handle burst traffic`` + diff --git a/source/configuration/global/options/rsconf1_maxopenfiles.rst b/source/configuration/global/options/rsconf1_maxopenfiles.rst new file mode 100644 index 0000000..89e4021 --- /dev/null +++ b/source/configuration/global/options/rsconf1_maxopenfiles.rst @@ -0,0 +1,36 @@ +$MaxOpenFiles +------------- + +**Available Since:** 4.3.0 + +**Type:** global configuration parameter + +**Default:** *operating system default* + +**Description:** + +Set the maximum number of files that the rsyslog process can have open +at any given time. Note that this includes open tcp sockets, so this +setting is the upper limit for the number of open TCP connections as +well. If you expect a large number of concurrent connections, it is +suggested that the number is set to the max number connected plus 1000. +Please note that each dynafile also requires up to 100 open file +handles. + +The setting is similar to running "ulimit -n number-of-files". + +Please note that depending on permissions and operating system +configuration, the setrlimit() request issued by rsyslog may fail, in +which case the previous limit is kept in effect. Rsyslog will emit a +warning message in this case. + +**Sample:** + +``$MaxOpenFiles 2000`` + +**Bugs:** + +For some reason, this settings seems not to work on all platforms. If +you experience problems, please let us know so that we can (hopefully) +narrow down the issue. + diff --git a/source/configuration/global/options/rsconf1_moddir.rst b/source/configuration/global/options/rsconf1_moddir.rst new file mode 100644 index 0000000..c1fa503 --- /dev/null +++ b/source/configuration/global/options/rsconf1_moddir.rst @@ -0,0 +1,20 @@ +$ModDir +------- + +**Type:** global configuration parameter + +**Default:** system default for user libraries, e.g. +/usr/local/lib/rsyslog/ + +**Description:** + +Provides the default directory in which loadable modules reside. This +may be used to specify an alternate location that is not based on the +system default. If the system default is used, there is no need to +specify this parameter. Please note that it is vitally important to end +the path name with a slash, else module loads will fail. + +**Sample:** + +``$ModDir /usr/rsyslog/libs/ # note the trailing slash!`` + diff --git a/source/configuration/global/options/rsconf1_modload.rst b/source/configuration/global/options/rsconf1_modload.rst new file mode 100644 index 0000000..e600784 --- /dev/null +++ b/source/configuration/global/options/rsconf1_modload.rst @@ -0,0 +1,30 @@ +$ModLoad +-------- + +**Type:** global configuration parameter + +**Default:** + +**Description:** + +Dynamically loads a plug-in into rsyslog's address space and activates +it. The plug-in must obey the rsyslog module API. Currently, only MySQL +and Postgres output modules are available as a plugins, but users may +create their own. A plug-in must be loaded BEFORE any configuration file +lines that reference it. + +Modules must be present in the system default destination for rsyslog +modules. You can also set the directory via the +`$ModDir <rsconf1_moddir.html>`_ parameter. + +If a full path name is specified, the module is loaded from that path. +The default module directory is ignored in that case. + +**Sample:** + +.. code-block:: none + + $ModLoad ommysql # load MySQL functionality + $ModLoad /rsyslog/modules/ompgsql.so # load the postgres module via absolute path + + diff --git a/source/configuration/global/options/rsconf1_resetconfigvariables.rst b/source/configuration/global/options/rsconf1_resetconfigvariables.rst new file mode 100644 index 0000000..8d27c65 --- /dev/null +++ b/source/configuration/global/options/rsconf1_resetconfigvariables.rst @@ -0,0 +1,19 @@ +$ResetConfigVariables +--------------------- + +**Type:** global configuration parameter + +**Default:** + +**Description:** + +Resets all configuration variables to their default value. Any settings +made will not be applied to configuration lines following the +$ResetConfigVariables. This is a good method to make sure no +side-effects exists from previous parameters. This parameter has no +parameters. + +**Sample:** + +``$ResetConfigVariables`` + diff --git a/source/configuration/global/options/rsconf1_umask.rst b/source/configuration/global/options/rsconf1_umask.rst new file mode 100644 index 0000000..57ead52 --- /dev/null +++ b/source/configuration/global/options/rsconf1_umask.rst @@ -0,0 +1,25 @@ +$UMASK +------ + +**Type:** global configuration parameter + +**Default:** + +**Description:** + +The $umask parameter allows to specify the rsyslogd processes' umask. If +not specified, the system-provided default is used. The value given must +always be a 4-digit octal number, with the initial digit being zero. + +If $umask is specified multiple times in the configuration file, results +may be somewhat unpredictable. It is recommended to specify it only +once. + +**Sample:** + +``$umask 0000`` + +This sample removes all restrictions. + +[`rsyslog site <http://www.rsyslog.com/>`_\ ] + diff --git a/source/configuration/global/options/rsyslog_confgraph_complex.png b/source/configuration/global/options/rsyslog_confgraph_complex.png Binary files differnew file mode 100644 index 0000000..21c04c5 --- /dev/null +++ b/source/configuration/global/options/rsyslog_confgraph_complex.png diff --git a/source/configuration/global/options/rsyslog_confgraph_std.png b/source/configuration/global/options/rsyslog_confgraph_std.png Binary files differnew file mode 100644 index 0000000..655a7f8 --- /dev/null +++ b/source/configuration/global/options/rsyslog_confgraph_std.png diff --git a/source/configuration/index.rst b/source/configuration/index.rst new file mode 100644 index 0000000..d1055b4 --- /dev/null +++ b/source/configuration/index.rst @@ -0,0 +1,62 @@ +Configuration +============= + +**Rsyslog Configuration Reference Manual Introduction** + +This document serves as a detailed guide to rsyslog configuration, offering extensive information on the setup and management of system logging using +`rsyslog <https://www.rsyslog.com>`_ +It covers various aspects of rsyslog configuration, including constructs, statements, and key concepts, designed to assist users in customizing their logging infrastructure according to specific needs. + +The primary configuration file for rsyslog, located at `/etc/rsyslog.conf`, acts as the central point for establishing logging rules. This file is used to define input modules, filters, actions, and global directives, facilitating the processes of log collection, filtering, routing, and formatting. + +Please note that this documentation is currently in the process of being refined to improve its clarity, structure, and accessibility. We value your patience and understanding during this phase and are committed to delivering a comprehensive and easy-to-navigate guide to rsyslog. + +For further exploration of rsyslog's configuration intricacies, please refer to the links provided below. This manual is designed to be a valuable resource for both experienced system administrators and those new to the field, aiming to fully leverage the capabilities of rsyslog. + +Note that **configurations can be built interactively** via the online +`rsyslog configuration builder <http://www.rsyslog.com/rsyslog-configuration-builder/>`_ tool. + +.. toctree:: + :maxdepth: 2 + + conf_formats + converting_to_new_format + sysklogd_format + basic_structure + templates + properties + property_replacer + filters + ../rainerscript/index + actions + input + parser + timezone + examples + index_directives + rsyslog_statistic_counter + modules/index + output_channels + droppriv + ipv6 + cryprov_gcry + dyn_stats + lookup_tables + percentile_stats + +`Configuration file examples can be found in the rsyslog +wiki <http://wiki.rsyslog.com/index.php/Configuration_Samples>`_. Also +keep the `rsyslog config +snippets <http://www.rsyslog.com/config-snippets/>`_ on your mind. These +are ready-to-use real building blocks for rsyslog configuration. + +There is also one sample file provided together with the documentation +set. If you do not like to read, be sure to have at least a quick look +at :download:`rsyslog-example.conf <rsyslog-example.conf>`. + +While rsyslogd contains enhancements over standard syslogd, efforts have +been made to keep the configuration file as compatible as possible. +While, for obvious reasons, :doc:`enhanced features <../features>` require +a different config file syntax, rsyslogd should be able to work with a +standard syslog.conf file. This is especially useful while you are +migrating from syslogd to rsyslogd. diff --git a/source/configuration/index_directives.rst b/source/configuration/index_directives.rst new file mode 100644 index 0000000..fb93a19 --- /dev/null +++ b/source/configuration/index_directives.rst @@ -0,0 +1,21 @@ +Legacy Configuration Directives +=============================== +All legacy configuration directives need to be specified on a line by their own +and must start with a dollar-sign. + +Note that legacy configuration directives that set object options (e.g. for +inputs or actions) only affect those objects that are defined via legacy +constructs. Objects defined via new-style RainerScript objects (e.g. +action(), input()) are **not** affected by legacy directives. The reason +is that otherwise we would again have the ability to mess up a configuration +file with hard to understand constructs. This is avoided by not permitting +to mix and match the way object values are set. + +.. toctree:: + :maxdepth: 2 + + config_param_types + global/index + input_directives/index + action/index + ruleset/index diff --git a/source/configuration/input.rst b/source/configuration/input.rst new file mode 100644 index 0000000..3e214d1 --- /dev/null +++ b/source/configuration/input.rst @@ -0,0 +1,32 @@ +Input +===== + +.. index:: ! input +.. _cfgobj_input: + +The ``input`` object, as its name suggests, describes message input sources. +Without input, no processing happens at all, because no messages enter the +rsyslog system. +Inputs are implemented via :doc:`input modules <modules/idx_input>`. + +The input object has different parameters: + +- those that apply to all input and are generally available for + all inputs. These are documented below. +- input-specific parameters. These are specific to a certain type of + input. They are documented by the :doc:`input module <modules/idx_input>` + in question. + +General Input Parameters +------------------------ + +Note: parameter names are case-insensitive. + +.. function:: type <type-string> + + *Mandatory* + + The ``<type-string>`` is a string identifying the input module as given + it each module's documentation. For example, the + :doc:`UDP syslog input <modules/imudp>` is named "imudp". + diff --git a/source/configuration/input_directives/index.rst b/source/configuration/input_directives/index.rst new file mode 100644 index 0000000..796b73e --- /dev/null +++ b/source/configuration/input_directives/index.rst @@ -0,0 +1,28 @@ +Legacy Directives affecting Input Modules +========================================= + +Legacy Directives affecting multiple Input Modules +-------------------------------------------------- +While these directives only affect input modules, they are global in +the sense that they cannot be overwritten for specific input +instances. So they apply globally for all inputs that support these +directives. + +.. toctree:: + :glob: + + rsconf1_allowedsender + rsconf1_dropmsgswithmaliciousdnsptrrecords + rsconf1_controlcharacterescapeprefix + rsconf1_droptrailinglfonreception + rsconf1_escape8bitcharsonreceive + rsconf1_escapecontrolcharactersonreceive + +immark-specific Directives +-------------------------- + +.. toctree:: + :glob: + + rsconf1_markmessageperiod + diff --git a/source/configuration/input_directives/rsconf1_allowedsender.rst b/source/configuration/input_directives/rsconf1_allowedsender.rst new file mode 100644 index 0000000..eb30054 --- /dev/null +++ b/source/configuration/input_directives/rsconf1_allowedsender.rst @@ -0,0 +1,71 @@ +$AllowedSender +-------------- + +**Type:** input configuration parameter + +**Default:** all allowed + +**Description:** + +*Note:* this feature is supported for backward-compatibility, only. +The rsyslog team recommends to use proper firewalling instead of +this feature. + +Allowed sender lists can be used to specify which remote systems are +allowed to send syslog messages to rsyslogd. With them, further hurdles +can be placed between an attacker and rsyslogd. If a message from a +system not in the allowed sender list is received, that message is +discarded. A diagnostic message is logged, so that the fact is recorded +(this message can be turned off with the "-w" rsyslogd command line +option). + +Allowed sender lists can be defined for UDP and TCP senders separately. +There can be as many allowed senders as needed. The syntax to specify +them is: + +:: + + $AllowedSender <type>, ip[/bits], ip[/bits] + +"$AllowedSender" is the parameter - it must be written exactly as shown +and the $ must start at the first column of the line. "<type>" is either "UDP" +or "TCP" (or "GSS", if this is enabled during compilation). +It must immediately be followed by the comma, else you will +receive an error message. "ip[/bits]" is a machine or network ip address +as in "192.0.2.0/24" or "127.0.0.1". If the "/bits" part is omitted, a +single host is assumed (32 bits or mask 255.255.255.255). "/0" is not +allowed, because that would match any sending system. If you intend to +do that, just remove all $AllowedSender parameters. If more than 32 bits +are requested with IPv4, they are adjusted to 32. For IPv6, the limit is +128 for obvious reasons. Hostnames, with and without wildcards, may also +be provided. If so, the result of revers DNS resolution is used for +filtering. Multiple allowed senders can be specified in a +comma-delimited list. Also, multiple $AllowedSender lines can be given. +They are all combined into one UDP and one TCP list. Performance-wise, +it is good to specify those allowed senders with high traffic volume +before those with lower volume. As soon as a match is found, no further +evaluation is necessary and so you can save CPU cycles. + +Rsyslogd handles allowed sender detection very early in the code, nearly +as the first action after receiving a message. This keeps the access to +potential vulnerable code in rsyslog at a minimum. However, it is still +a good idea to impose allowed sender limitations via firewalling. + +**WARNING:** by UDP design, rsyslogd can not identify a spoofed sender +address in UDP syslog packets. As such, a malicious person could spoof +the address of an allowed sender, send such packets to rsyslogd and +rsyslogd would accept them as being from the faked sender. To prevent +this, use syslog via TCP exclusively. If you need to use UDP-based +syslog, make sure that you do proper egress and ingress filtering at the +firewall and router level. + +Rsyslog also detects some kind of malicious reverse DNS entries. In any +case, using DNS names adds an extra layer of vulnerability. We recommend +to stick with hard-coded IP addresses wherever possible. + +**Sample:** + +:: + + $AllowedSender UDP, 127.0.0.1, 192.0.2.0/24, [::1]/128, *.example.net, somehost.example.com + diff --git a/source/configuration/input_directives/rsconf1_controlcharacterescapeprefix.rst b/source/configuration/input_directives/rsconf1_controlcharacterescapeprefix.rst new file mode 100644 index 0000000..06ddb12 --- /dev/null +++ b/source/configuration/input_directives/rsconf1_controlcharacterescapeprefix.rst @@ -0,0 +1,24 @@ +$ControlCharacterEscapePrefix +----------------------------- + +**Type:** global configuration parameter + +**Default:** \\ + +**Description:** + +This option specifies the prefix character to be used for control +character escaping (see option $EscapeControlCharactersOnReceive). By +default, it is '\\', which is backwards-compatible with sysklogd. Change +it to '#' in order to be compliant to the value that is somewhat +suggested by Internet-Draft syslog-protocol. + +**IMPORTANT**: do not use the ' character. This is reserved and will +most probably be used in the future as a character delimiter. For the +same reason, the syntax of this parameter will probably change in future +releases. + +**Sample:** + +``$EscapeControlCharactersOnReceive # # as of syslog-protocol`` + diff --git a/source/configuration/input_directives/rsconf1_dropmsgswithmaliciousdnsptrrecords.rst b/source/configuration/input_directives/rsconf1_dropmsgswithmaliciousdnsptrrecords.rst new file mode 100644 index 0000000..81562ef --- /dev/null +++ b/source/configuration/input_directives/rsconf1_dropmsgswithmaliciousdnsptrrecords.rst @@ -0,0 +1,22 @@ +$DropMsgsWithMaliciousDnsPTRRecords +----------------------------------- + +**Type:** global configuration parameter + +**Default:** off + +**Description:** + +Rsyslog contains code to detect malicious DNS PTR records (reverse name +resolution). An attacker might use specially-crafted DNS entries to make +you think that a message might have originated on another IP address. +Rsyslog can detect those cases. It will log an error message in any +case. If this option here is set to "on", the malicious message will be +completely dropped from your logs. If the option is set to "off", the +message will be logged, but the original IP will be used instead of the +DNS name. + +**Sample:** + +``$DropMsgsWithMaliciousDnsPTRRecords on`` + diff --git a/source/configuration/input_directives/rsconf1_droptrailinglfonreception.rst b/source/configuration/input_directives/rsconf1_droptrailinglfonreception.rst new file mode 100644 index 0000000..1f69195 --- /dev/null +++ b/source/configuration/input_directives/rsconf1_droptrailinglfonreception.rst @@ -0,0 +1,21 @@ +$DropTrailingLFOnReception +-------------------------- + +**Type:** global configuration parameter + +**Default:** on + +**Description:** + +Syslog messages frequently have the line feed character (LF) as the last +character of the message. In almost all cases, this LF should not really +become part of the message. However, recent IETF syslog standardization +recommends against modifying syslog messages (e.g. to keep digital +signatures valid). This option allows to specify if trailing LFs should +be dropped or not. The default is to drop them, which is consistent with +what sysklogd does. + +**Sample:** + +``$DropTrailingLFOnReception on`` + diff --git a/source/configuration/input_directives/rsconf1_escape8bitcharsonreceive.rst b/source/configuration/input_directives/rsconf1_escape8bitcharsonreceive.rst new file mode 100644 index 0000000..7377f65 --- /dev/null +++ b/source/configuration/input_directives/rsconf1_escape8bitcharsonreceive.rst @@ -0,0 +1,39 @@ +$Escape8BitCharactersOnReceive +------------------------------ + +**Type:** global configuration parameter + +**Default:** off + +**Available Since:** 5.5.2 + +**Description:** + +This parameter instructs rsyslogd to replace non US-ASCII characters +(those that have the 8th bit set) during reception of the message. This +may be useful for some systems. Please note that this escaping breaks +Unicode and many other encodings. Most importantly, it can be assumed +that Asian and European characters will be rendered hardly readable by +this settings. However, it may still be useful when the logs themselves +are primarily in English and only occasionally contain local script. If +this option is turned on, all control-characters are converted to a +3-digit octal number and be prefixed with the +$ControlCharacterEscapePrefix character (being '#' by default). + +**Warning:** + +- turning on this option most probably destroys non-western character + sets (like Japanese, Chinese and Korean) as well as European + character sets. +- turning on this option destroys digital signatures if such exists + inside the message +- if turned on, the drop-cc, space-cc and escape-cc `property + replacer <property_replacer.html>`_ options do not work as expected + because control characters are already removed upon message + reception. If you intend to use these property replacer options, you + must turn off $Escape8BitCharactersOnReceive. + +**Sample:** + +``$Escape8BitCharactersOnReceive on`` + diff --git a/source/configuration/input_directives/rsconf1_escapecontrolcharactersonreceive.rst b/source/configuration/input_directives/rsconf1_escapecontrolcharactersonreceive.rst new file mode 100644 index 0000000..05cc623 --- /dev/null +++ b/source/configuration/input_directives/rsconf1_escapecontrolcharactersonreceive.rst @@ -0,0 +1,34 @@ +$EscapeControlCharactersOnReceive +--------------------------------- + +**Type:** global configuration parameter + +**Default:** on + +**Description:** + +This parameter instructs rsyslogd to replace control characters during +reception of the message. The intent is to provide a way to stop +non-printable messages from entering the syslog system as whole. If this +option is turned on, all control-characters are converted to a 3-digit +octal number and be prefixed with the $ControlCharacterEscapePrefix +character (being '\\' by default). For example, if the BEL character +(ctrl-g) is included in the message, it would be converted to "\\007". +To be compatible to sysklogd, this option must be turned on. + +**Warning:** + +- turning on this option most probably destroys non-western character + sets (like Japanese, Chinese and Korean) +- turning on this option destroys digital signatures if such exists + inside the message +- if turned on, the drop-cc, space-cc and escape-cc `property + replacer <property_replacer.html>`_ options do not work as expected + because control characters are already removed upon message + reception. If you intend to use these property replacer options, you + must turn off $EscapeControlCharactersOnReceive. + +**Sample:** + +``$EscapeControlCharactersOnReceive on`` + diff --git a/source/configuration/input_directives/rsconf1_markmessageperiod.rst b/source/configuration/input_directives/rsconf1_markmessageperiod.rst new file mode 100644 index 0000000..074cc95 --- /dev/null +++ b/source/configuration/input_directives/rsconf1_markmessageperiod.rst @@ -0,0 +1,26 @@ +$MarkMessagePeriod +------------------ + +**Type:** specific to immark input module + +**Default:** 1200 (20 minutes) + +**Description:** + +This specifies when mark messages are to be written to output modules. +The time specified is in seconds. Specifying 0 is possible and disables +mark messages. In that case, however, it is more efficient to NOT load +the immark input module. + +So far, there is only one mark message process and any subsequent +$MarkMessagePeriod overwrites the previous. + +**This parameter is only available after the immark input module has +been loaded.** + +**Sample:** + +``$MarkMessagePeriod 600 # mark messages appear every 10 Minutes`` + +**Available since:** rsyslog 3.0.0 + diff --git a/source/configuration/ipv6.rst b/source/configuration/ipv6.rst new file mode 100644 index 0000000..aeec21d --- /dev/null +++ b/source/configuration/ipv6.rst @@ -0,0 +1,47 @@ +Notes on IPv6 Handling in Rsyslog +================================= + +**Rsyslog fully\* supports sending and receiving syslog messages via +both IPv4 and IPv6.** IPv6 is natively supported for both UDP and TCP. +However, there are some options that control handling of IPv6 +operations. I thought it is is a good idea to elaborate a little about +them, so that you can probably find your way somewhat easier. + +First of all, you can restrict rsyslog to using IPv4 or IPv6 addresses +only by specifying the -4 or -6 command line option (now guess which one +does what...). If you do not provide any command line option, rsyslog +uses IPv4 and IPv6 addresses concurrently. In practice, that means the +listener binds to both addresses (provided they are configured). When +sending syslog messages, rsyslog uses IPv4 addresses when the receiver +can be reached via IPv4 and IPv6 addresses if it can be reached via +IPv6. If it can be reached on either IPv4 and v6, rsyslog leaves the +choice to the socket layer. The important point to know is that it uses +whatever connectivity is available to reach the destination. + +**There is one subtle difference between UDP and TCP.** With the new +IPv4/v6 ignorant code, rsyslog has potentially different ways to reach +destinations. The socket layer returns all of these paths in a sorted +array. For TCP, rsyslog loops through this array until a successful TCP +connect can be made. If that happens, the other addresses are ignored +and messages are sent via the successfully-connected socket. + +For UDP, there is no such definite success indicator. Sure, the socket +layer may detect some errors, but it may not notice other errors (due to +the unreliable nature of UDP). By default, the UDP sender also tries one +entry after the other in the sorted array of destination addresses. When +a send fails, the next address is tried. When the send function finally +succeeds, rsyslogd assumes the UDP packet has reached its final +destination. However, if rsyslogd is started with the "-A" (capital A!) +was given on the command line, rsyslogd will continue to send messages +until the end of the destination address array is reached. This may +result in duplicate messages, but it also provides some additional +reliability in case a message could not be received. You need to be sure +about the implications before applying this option. In general, it is +NOT recommended to use the -A option. + +**\***\ rsyslog does not support RFC 3195 over IPv6. The reason is that +the RFC 3195 library, `liblogging <http://www.liblogging.org/>`_, +supports IPv4, only. Currently, there are no plans to update either +rsyslog to another RFC 3195 stack or update liblogging. There is simply +no demand for 3195 solutions. + diff --git a/source/configuration/lookup_tables.rst b/source/configuration/lookup_tables.rst new file mode 100644 index 0000000..b673022 --- /dev/null +++ b/source/configuration/lookup_tables.rst @@ -0,0 +1,251 @@ +Lookup Tables +============= + +Lookup tables are a powerful construct to obtain *class* information based +on message content. It works on top of a data-file which maps key (to be looked +up) to value (the result of lookup). + +The idea is to use a message properties (or derivatives of it) as an index +into a table which then returns another value. For example, $fromhost-ip +could be used as an index, with the table value representing the type of +server or the department or remote office it is located in. + +This can be emulated using if and else-if stack, but implementing it as a +dedicated component allows ``lookup`` to be made fast. + +The lookup tables itself exists in a separate data file (one per +table). This file is loaded on Rsyslog startup and when a reload is requested. + +There are different types of lookup tables (identified by "type" field in json data-file). + +Types +^^^^^ + +string +------ + +The key to be looked up is an arbitrary string. + +**Match criterion**: The key must be exactly equal to index from one of the entries. + +array +----- + +The value to be looked up is an integer number from a consecutive set. +The set does not need to start at zero or one, but there must be no number missing. +So, for example ``5,6,7,8,9`` would be a valid set of index values, while ``1,2,4,5`` would +not be (due to missing ``3``). + +**Match criterion**: Looked-up number(key) must be exactly equal to index from one of the entries. + +sparseArray +----------- + +The value to be looked up is an integer value, but there may be gaps inside the +set of values (usually there are large gaps). A typical use case would be the +matching of IPv4 address information. + +**Match criterion**: A match happens on the first index that is less than or equal to the looked-up key. + +Note that index integer numbers are represented by unsigned 32 bits. + + +Lookup Table File Format +^^^^^^^^^^^^^^^^^^^^^^^^ + +Lookup table files contain a single JSON object. This object consists of a header and a table part. + +**Header** + +The header is the top-level json. +It has parameters "version", "nomatch", and "type". + +Parameters: + **version** <number, default: 1> : Version of table-definition format (so improvements in the future can be managed in a backward compatible way). + + **nomatch** <string literal, default: ""> : Value to be returned for a lookup when match fails. + + **type** <*string*, *array* or *sparseArray*, default: *string*> : Type of lookup-table (controls how matches are performed). + +**Table** + +This must be an array of elements, even if only a single value exists (for obvious reasons, +we do not expect this to occur often). Each array element must contain two fields "index" +and "value". + +This is a sample of how an ip-to-office mapping may look like: + +:: + + { "version" : 1, + "nomatch" : "unk", + "type" : "string", + "table" : [ + {"index" : "10.0.1.1", "value" : "A" }, + {"index" : "10.0.1.2", "value" : "A" }, + {"index" : "10.0.1.3", "value" : "A" }, + {"index" : "10.0.2.1", "value" : "B" }, + {"index" : "10.0.2.2", "value" : "B" }, + {"index" : "10.0.2.3", "value" : "B" }]} + + +Note: In the example above, if a different IP comes in, the value "unk" is returned thanks to the nomatch parameter in the first line. + +Lookup tables can be accessed via the ``lookup()`` built-in function. A common usage pattern is to set a local variable to the lookup result and later use that variable in templates. + + + +Lookup-table configuration +^^^^^^^^^^^^^^^^^^^^^^^^^^ + +Lookup-table configuration involves a **two part setup** (definition and usage(lookup)), with an optional third part, +which allows reloading table using internal trigger. + +lookup_table(name="<table>" file="</path/to/file>"...) (object) +--------------------------------------------------------------- + +**Defines** the table(identified by the table-name) and allows user to set some properties that control behavior of the table. + +:: + + lookup_table(name="msg_per_host") + +Parameters: + **name** <string literal, mandatory> : Name of the table. + + **file** <string literal, file path, mandatory> : Path to external json database file. + + **reloadOnHUP** <on|off, default: on> : Whether or not table should be reloaded when process receives HUP signal. + +A definition setting all the parameters looks like: + +:: + + lookup_table(name="host_bu" file="/var/lib/host_billing_unit_mapping.json" reloadOnHUP="on") + + +lookup("<table>", <expr>) (function) +------------------------------------ + +**Looks up** and returns the value that is associated with the given key (passed as <variable>) +in lookup table identified by table-name. If no match is found (according to table-type +matching-criteria specified above), the "nomatch" string is returned (or an empty string if it is not defined). + +Parameters: + **name** <string literal, mandatory> : Name of the table. + + **expr** <expression resulting in string or number according to lookup-table type, mandatory> : Key to be looked up. + +A ``lookup`` call looks like: + +:: + + set $.bu = lookup("host_bu", $hostname); + + if ($.bu == "unknown") then { + .... + } + +Some examples of different match/no-match scenarios: + +**string table**: + +:: + + { "nomatch" : "none", + "type" : "string", + "table":[ + {"index" : "foo", "value" : "bar" }, + {"index" : "baz", "value" : "quux" }]} + +Match/no-Match behaviour: + +====== ============== +key return +====== ============== +foo bar +baz quux +corge none +====== ============== + +**array table**: + +:: + + { "nomatch" : "nothing", + "type" : "array", + "table":[ + {"index" : 9, "value" : "foo" }, + {"index" : 10, "value" : "bar" }, + {"index" : 11, "value" : "baz" }]} + +Match/no-Match behaviour: + +====== ============== +key return +====== ============== +9 foo +11 baz +15 nothing +0 nothing +====== ============== + +**sparseArray table**: + +:: + + { "nomatch" : "no_num", + "type" : "sparseArray", + "table":[ + {"index" : "9", "value" : "foo" }, + {"index" : "11", "value" : "baz" }]} + +Match/no-Match behaviour: + +====== ============== +key return +====== ============== +8 no_num +9 foo +10 foo +11 baz +12 baz +100 baz +====== ============== + + +reload_lookup_table("<table>", "<stub value>") (statement) +---------------------------------------------------------- + +**Reloads** lookup table identified by given table name **asynchronously** (by internal trigger, as opposed to HUP). + +This statement isn't always useful. It needs to be used only when lookup-table-reload needs to be triggered in response to +a message. + +Messages will continue to be processed while table is asynchronously reloaded. + +Note: For performance reasons, message that triggers reload should be accepted only from a trusted source. + +Parameters: + **name** <string literal, mandatory> : Name of the table. + + **stub value** <string literal, optional> : Value to stub the table in-case reload-attempt fails. + +A ``reload_lookup_table`` invocation looks like: + +:: + + if ($.do_reload == "y") then { + reload_lookup_table("host_bu", "unknown") + } + + +Implementation Details +^^^^^^^^^^^^^^^^^^^^^^ + +The lookup table functionality is implemented via efficient algorithms. + +The string and sparseArray lookup have O(log(n)) time complexity, while array lookup is O(1). + +To preserve space and, more important, increase cache hit performance, equal data values are only stored once, +no matter how often a lookup index points to them. diff --git a/source/configuration/modules/gssapi.png b/source/configuration/modules/gssapi.png Binary files differnew file mode 100644 index 0000000..c82baa5 --- /dev/null +++ b/source/configuration/modules/gssapi.png diff --git a/source/configuration/modules/gssapi.rst b/source/configuration/modules/gssapi.rst new file mode 100644 index 0000000..157f5a3 --- /dev/null +++ b/source/configuration/modules/gssapi.rst @@ -0,0 +1,73 @@ +GSSAPI module support in rsyslog v3 +=================================== + +What is it good for. + +- client-serverauthentication +- Log messages encryption + +Requirements. + +- Kerberos infrastructure +- rsyslog, rsyslog-gssapi + +Configuration. + +Let's assume there are 3 machines in Kerberos Realm: + +- the first is running KDC (Kerberos Authentication Service and Key + Distribution Center), +- the second is a client sending its logs to the server, +- the third is receiver, gathering all logs. + +1. KDC: + +- Kerberos database must be properly set-up on KDC machine first. Use + kadmin/kadmin.local to do that. Two principals need to be add in our + case: + +#. sender@REALM.ORG + +- client must have ticket for principal sender +- REALM.ORG is kerberos Realm + +#. host/receiver.mydomain.com@REALM.ORG - service principal + +- Use ktadd to export service principal and transfer it to + /etc/krb5.keytab on receiver + +2. CLIENT: + +- set-up rsyslog, in /etc/rsyslog.conf +- $ModLoad omgssapi - load output gss module +- $GSSForwardServiceName otherThanHost - set the name of service + principal, "host" is the default one +- \*.\* :omgssapi:receiver.mydomain.com - action line, forward logs to + receiver +- kinit root - get the TGT ticket +- service rsyslog start + +3. SERVER: + +- set-up rsyslog, in /etc/rsyslog.conf + +- $ModLoad `imgssapi <imgssapi.html>`_ - load input gss module + +- $InputGSSServerServiceName otherThanHost - set the name of service + principal, "host" is the default one + +- $InputGSSServerPermitPlainTCP on - accept GSS and TCP connections + (not authenticated senders), off by default + +- $InputGSSServerRun 514 - run server on port + +- service rsyslog start + +The picture demonstrate how things work. + +.. figure:: gssapi.png + :align: center + :alt: rsyslog gssapi support + + rsyslog gssapi support + diff --git a/source/configuration/modules/idx_input.rst b/source/configuration/modules/idx_input.rst new file mode 100644 index 0000000..74f485c --- /dev/null +++ b/source/configuration/modules/idx_input.rst @@ -0,0 +1,13 @@ +Input Modules +------------- + +Input modules are used to gather messages from various sources. They +interface to message generators. They are generally defined via the +:doc:`input <../input>` configuration object. + +.. toctree:: + :glob: + :maxdepth: 1 + + im* + diff --git a/source/configuration/modules/idx_library.rst b/source/configuration/modules/idx_library.rst new file mode 100644 index 0000000..62452a1 --- /dev/null +++ b/source/configuration/modules/idx_library.rst @@ -0,0 +1,9 @@ +Library Modules +=============== + +Library modules provide dynamically loadable functionality for parts of +rsyslog, most often for other loadable modules. They can not be +user-configured and are loaded automatically by some components. They +are just mentioned so that error messages that point to library modules +can be understood. No module list is provided. + diff --git a/source/configuration/modules/idx_messagemod.rst b/source/configuration/modules/idx_messagemod.rst new file mode 100644 index 0000000..f29c6af --- /dev/null +++ b/source/configuration/modules/idx_messagemod.rst @@ -0,0 +1,15 @@ +Message Modification Modules +---------------------------- + +Message modification modules are used to change the content of messages +being processed. They can be implemented using either the output module +or the parser module interface. From the rsyslog core's point of view, +they actually are output or parser modules, it is their implementation +that makes them special. + +.. toctree:: + :maxdepth: 1 + :glob: + + mm* + diff --git a/source/configuration/modules/idx_output.rst b/source/configuration/modules/idx_output.rst new file mode 100644 index 0000000..0be3046 --- /dev/null +++ b/source/configuration/modules/idx_output.rst @@ -0,0 +1,16 @@ +Output Modules +-------------- + +Output modules process messages. With them, message formats can be +transformed and messages be transmitted to various different targets. +They are generally defined via :doc:`action <../actions>` configuration +objects. + +.. toctree:: + :glob: + :maxdepth: 1 + + om* + sigprov_gt + sigprov_ksi + sigprov_ksi12 diff --git a/source/configuration/modules/idx_parser.rst b/source/configuration/modules/idx_parser.rst new file mode 100644 index 0000000..220f2ca --- /dev/null +++ b/source/configuration/modules/idx_parser.rst @@ -0,0 +1,16 @@ +Parser Modules +-------------- + +Parser modules are used to parse message content, once the message has +been received. They can be used to process custom message formats or +invalidly formatted messages. For details, please see the :doc:`rsyslog +message parser documentation <../../concepts/messageparser>`. + +The current modules are currently provided as part of rsyslog: + +.. toctree:: + :glob: + :maxdepth: 1 + + pm* + diff --git a/source/configuration/modules/idx_stringgen.rst b/source/configuration/modules/idx_stringgen.rst new file mode 100644 index 0000000..221f0d4 --- /dev/null +++ b/source/configuration/modules/idx_stringgen.rst @@ -0,0 +1,43 @@ +String Generator Modules +======================== + +String generator modules are used, as the name implies, to generate +strings based on the message content. They are currently tightly coupled +with the template system. Their primary use is to speed up template +processing by providing a native C interface to template generation. +These modules exist since 5.5.6. To get an idea of the potential +speedup, the default file format, when generated by a string generator, +provides a roughly 5% speedup. For more complex strings, especially +those that include multiple regular expressions, the speedup may be +considerably higher. + +String generator modules are written to a quite simple interface. +However, a word of caution is due: they access the rsyslog message +object via a low-level interface. That interface is not guaranteed yet +to stay stable. So it may be necessary to modify string generator +modules if the interface changes. Obviously, we will not do that without +good reason, but it may happen. + +Rsyslog comes with a set of core, build-in string generators, which are +used to provide those default templates that we consider to be +time-critical: + +- smfile - the default rsyslog file format +- smfwd - the default rsyslog (network) forwarding format +- smtradfile - the traditional syslog file format +- smfwd - the traditional syslog (network) forwarding format + +Note that when you replace these defaults with some custom strings, you +will loose some performance (around 5%). For typical systems, this is +not really relevant. But for a high-performance systems, it may be very +relevant. To solve that issue, create a new string generator module for +your custom format, starting out from one of the default generators +provided. If you can not do this yourself, you may want to contact +`Adiscon <mailto:info%40adiscon.com>`_ as we offer custom development of +string generators at a very low price. + +Note that string generator modules can be dynamically loaded. However, +the default ones provided are so important that they are build right +into the executable. But this does not need to be done that way (and it +is straightforward to do it dynamic). + diff --git a/source/configuration/modules/im3195.rst b/source/configuration/modules/im3195.rst new file mode 100644 index 0000000..10a2d54 --- /dev/null +++ b/source/configuration/modules/im3195.rst @@ -0,0 +1,75 @@ +**************************** +im3195: RFC3195 Input Module +**************************** + +=========================== =========================================================================== +**Module Name:** **im3195** +**Author:** `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com> +=========================== =========================================================================== + + +Purpose +======= + +Receives syslog messages via RFC 3195. The RAW profile is fully +implemented and the COOKED profile is provided in an experimental state. +This module uses `liblogging <http://www.liblogging.org>`_ for the +actual protocol handling. + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + + +Input Parameter +--------------- + +Input3195ListenPort +^^^^^^^^^^^^^^^^^^^ + +.. note:: + + Parameter is only available in Legacy Format. + + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "601", "no", "``$Input3195ListenPort``" + +The port on which imklog listens for RFC 3195 messages. The default +port is 601 (the IANA-assigned port) + + +Caveats/Known Bugs +================== + +Due to no demand at all for RFC3195, we have converted rfc3195d to this +input module, but we have NOT conducted any testing. Also, the module +does not yet properly handle the recovery case. If someone intends to +put this module into production, good testing should be conducted. It +also is a good idea to notify the rsyslog project that you intend to use +it in production. In this case, we'll probably give the module another +cleanup. We don't do this now because so far it looks just like a big +waste of time. + +Currently only a single listener can be defined. That one binds to all +interfaces. + +Example +======= + +The following sample accepts syslog messages via RFC 3195 on port 1601. + +.. code-block:: none + + $ModLoad im3195 + $Input3195ListenPort 1601 + + diff --git a/source/configuration/modules/imbatchreport.rst b/source/configuration/modules/imbatchreport.rst new file mode 100644 index 0000000..439eae4 --- /dev/null +++ b/source/configuration/modules/imbatchreport.rst @@ -0,0 +1,222 @@ +**************************************** +imbatchreport: Batch report input module +**************************************** + +================ ============================================================== +**Module Name:** **imbatchreport** +**Authors:** Jean-Philippe Hilaire <jean-philippe.hilaire@pmu.fr> & Philippe Duveau <philippe.duveau@free.fr> +================ ============================================================== + + +Purpose +======= + +This module allows rsyslog to manage batch reports. + +Batch are programs launched successively to process a large amount of +information. These programs are organized in stages with passing conditions. +The batch ends with a global execution summary. Each Batch produces a single +result file usually named with the name of the batch and its date of execution. + +Those files have sense only when they are complete in one log. When the file is +collected it becomes useless and, as a statefile, should be deleted or renamed. + +This module handle those characteristics : + +- reads the complete file, + +- extracts the structured data from the file (see managing structured data), + +- transmit the message to output module(s), + +- action is applied to the file to flag it as treated. Two different actions can be applied: delete or rename the file. + +If the file is too large to be handled in the message size defined by rsyslog, +the file is renamed as a "rejected file". See \$maxMessageSize + +**Managing structured data** + +As part of the batch summary, the structure data can be provided in the batch +report file as the last part of the file. + +The last non-space char has to be a closing brace ']' then all chars between +this char up to the closest opening brace '[' are computed as structured data. + +All the structured data has to be contained in the last 150 chars of the file. + +In general, structured data should contain the batch name (program) and the +start timestamp. Those two values can be extract to fill rsyslog message +attributes. + +Compile +======= + +To successfully compile imbatchreport module. + + ./configure --enable-imbatchreport ... + +Configuration Parameters +======================== + +Action Parameters +----------------- + +Reports +^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "yes", "glob definition", + +Glob definition used to identify reports to manage. + +Tag +^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "yes", ,"none" + +The tag to be assigned to messages read from this file. If you would like to +see the colon after the tag, you need to include it when you assign a tag +value, like so: ``tag="myTagValue:"``. + +Facility +^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "no", "facility\|number", "local0" + +The syslog facility to be assigned to messages read from this file. Can be +specified in textual form (e.g. ``local0``, ``local1``, ...) or as numbers (e.g. +16 for ``local0``). Textual form is suggested. + +Severity +^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "no", "severity\|number", "notice" + +The syslog severity to be assigned to lines read. Can be specified +in textual form (e.g. ``info``, ``warning``, ...) or as numbers (e.g. 6 +for ``info``). Textual form is suggested. + +DeduplicateSpaces +^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "binary", "no", "", "on" + +The parameter modify the way consecutive spaces like chars are managed. +When it is setted to "on", consecutive spaces like chars are reduced to a single one +and trailing space like chars are suppressed. + +Delete +^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "no", "<regex> <reject>", + +This parameter informs the module to delete the report to flag it as treated. +If the file is too large (or failed to be removed) it is renamed using the +<regex> to identify part of the file name that has to be replaced it by +<reject>. See Examples + +Rename +^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "no", "<regex> <sent> <reject>", + +This parameter informs the module to rename the report to flag it as treated. +The file is renamed using the <regex> to identify part of the file name that +has to be replaced it: + +- by <rename> if the file was successfully treated, + +- by <reject> if the file is too large to be sent. + +See #Examples + +Programkey +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "no", , + +The attribute in structured data which contains the rsyslog APPNAME. +This attribute has to be a String between double quotes ("). + +Timestampkey +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "no", , + +The attribute in structured data which contains the rsyslog TIMESTAMP. +This attribute has to be a Number (Unix TimeStamp). + +Examples +======== + +The example show the delete action. All files corresponding to +"/test/\*.ok" will be treated as batch reports and will be deleted +on success or renamed from <file>.ok to <file>.rejected in other +cases. + +.. code-block:: none + + module(load="imbatchreport") + input(type="imbatchreport" reports="/test/\*.ok" + ruleset="myruleset" tag="batch" + delete=".ok$ .rejected" + programkey="SHELL" timestampkey="START" + ) + +The example show the rename action. All files corresponding to +"/test/\*.ok" will be treated as batch reports and will be renamed +from <file>.ok to <file>.sent on success or +renamed from <file>.ok to <file>.rejected in other cases. + +.. code-block:: none + + module(load="imbatchreport") + input(type="imbatchreport" reports="/test/\*.ok" + ruleset="myruleset" tag="batch" + rename=".ok$ .sent .rejected" + programkey="SHELL" timestampkey="START" + ) diff --git a/source/configuration/modules/imdocker.rst b/source/configuration/modules/imdocker.rst new file mode 100644 index 0000000..8c47b8f --- /dev/null +++ b/source/configuration/modules/imdocker.rst @@ -0,0 +1,268 @@ +*************************************** +imdocker: Docker Input Module +*************************************** + +=========================== =========================================================================== +**Module Name:** **imdocker** +**Author:** Nelson Yen +**Available since:** 8.41.0 +=========================== =========================================================================== + + +Purpose +======= + +The imdocker input plug-in provides the ability to receive container logs from Docker (engine) +via the Docker Rest API. + +Other features include: + +- filter containers through the plugin options +- handle long log lines (greater than 16kb) and obtain +- container metadata, such as container id, name, image id, labels, etc. + +**Note**: Multiple docker instances are not supported at the time of this writing. + + +Configuration Parameters +======================== + +The configuration parameters for this module are designed for tailoring +the behavior of imdocker. + +.. note:: + + Parameter names are case-insensitive. + +.. note:: + + This module supports module parameters, only. + + + +Module Parameters +----------------- + + +DockerApiUnixSockAddr +^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "/var/run/docker.sock", "no", "none" + +Specifies the Docker unix socket address to use. + +ApiVersionStr +^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "v1.27", "no", "none" + +Specifies the version of Docker API to use. Must be in the format specified by the +Docker api, e.g. similar to the default above (v1.27, v1.28, etc). + + +PollingInterval +^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "60", "no", "none" + +Specifies the polling interval in seconds, imdocker will poll for new containers by +calling the 'List containers' API from the Docker engine. + + +ListContainersOptions +^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "", "no", "none" + +Specifies the http query component of the a 'List Containers' HTTP API request. +See Docker API for more information about available options. +**Note**: It is not necessary to prepend the string with '?'. + + +GetContainerLogOptions +^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "timestamp=0&follow=1&stdout=1&stderr=1&tail=1", "no", "none" + +Specifies the http query component of the a 'Get container logs' HTTP API request. +See Docker API for more information about available options. +**Note**: It is not necessary to prepend the string with '?'. + + +RetrieveNewLogsFromStart +^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "1", "no", "none" + +This option specifies the whether imdocker will process newly found container logs from the beginning. +The exception is for containers found on start-up. The container logs for containers +that were active at imdocker start-up are controlled via 'GetContainerLogOptions', the +'tail' in particular. + + +DefaultFacility +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer or string (preferred)", "user", "no", "``$InputFileFacility``" + +The syslog facility to be assigned to log messages received. Specified as numbers. + +.. seealso:: + + https://en.wikipedia.org/wiki/Syslog + + +DefaultSeverity +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer or string (preferred)", "notice", "no", "``$InputFileSeverity``" + +The syslog severity to be assigned to log messages received. Specified as numbers (e.g. 6 +for ``info``). Textual form is suggested. Default is ``notice``. + +.. seealso:: + + https://en.wikipedia.org/wiki/Syslog + + +escapeLF +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "none" + +This is only meaningful if multi-line messages are to be processed. +LF characters embedded into syslog messages cause a lot of trouble, +as most tools and even the legacy syslog TCP protocol do not expect +these. If set to "on", this option avoid this trouble by properly +escaping LF characters to the 4-byte sequence "#012". This is +consistent with other rsyslog control character escaping. By default, +escaping is turned on. If you turn it off, make sure you test very +carefully with all associated tools. Please note that if you intend +to use plain TCP syslog with embedded LF characters, you need to +enable octet-counted framing. +For more details, see Rainer's blog posting on imfile LF escaping. + + +Metadata +======== +The imdocker module supports message metadata. It supports the following +data items: + +- **Id** - the container id associated with the message. + +- **Names** - the first container associated with the message. + +- **ImageID** - the image id of the container associated with the message. + +- **Labels** - all the labels of the container associated with the message in json format. + +**Note**: At the time of this writing, metadata is always enabled. + + +Statistic Counter +================= + +This plugin maintains `statistics <http://www.rsyslog.com/rsyslog-statistic-counter/>`. The statistic is named "imdocker". + +The following properties are maintained for each listener: + +- **submitted** - total number of messages submitted to main queue after reading from journal for processing + since startup. All records may not be submitted due to rate-limiting. + +- **ratelimit.discarded** - number of messages discarded due to rate-limiting within configured + rate-limiting interval. + +- **curl.errors** - total number of curl errors. + + +Caveats/Known Bugs +================== + +- At the moment, this plugin only supports a single instance of docker on a host. + + +Configuration Examples +====================== + +Load module, with only defaults +-------------------------------- + +This activates the module with all the default options: + +.. code-block:: none + + module(load="imdocker") + + +Load module, with container filtering +------------------------------------- + +This activates the module with container filtering on a label: + +.. code-block:: none + + module(load="imdocker" + DockerApiUnixSockAddr="/var/run/docker.sock" + ApiVersionStr="v1.27" + PollingInterval="60" + ListContainersOptions="filters={\"label\":[\"log_opt_enabled\"]}" + GetContainerLogOptions="timestamps=0&follow=1&stdout=1&stderr=0&tail=1" + ) + + +Example template to get container metadata +------------------------------------------ + +An example of how to create a template with container metadata + +.. code-block:: none + + template (name="ImdockerFormat" type="string" + string="program:%programname% tag:%syslogtag% id:%$!metadata!Id% name:%$!metadata!Names% imageid:%$!metadata!ImageID% labels:%$!metadata!Labels% msg: %msg%\n" + ) + diff --git a/source/configuration/modules/imfile.rst b/source/configuration/modules/imfile.rst new file mode 100644 index 0000000..cc11742 --- /dev/null +++ b/source/configuration/modules/imfile.rst @@ -0,0 +1,948 @@ +****************************** +imfile: Text File Input Module +****************************** + +.. index:: ! imfile + +=========================== =========================================================================== +**Module Name:** **imfile** +**Author:** `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com> +=========================== =========================================================================== + +Purpose +======= + +This module provides the ability to convert any standard text file +into a syslog +message. A standard text file is a file consisting of printable +characters with lines being delimited by LF. + +The file is read line-by-line and any line read is passed to rsyslog's +rule engine. The rule engine applies filter conditions and selects which +actions needs to be carried out. Empty lines are **not** processed, as +they would result in empty syslog records. They are simply ignored. + +As new lines are written they are taken from the file and processed. +Depending on the selected mode, this happens via inotify or based on +a polling interval. Especially in polling mode, file reading doesn't +happen immediately. But there are also slight delays (due to process +scheduling and internal processing) in inotify mode. + +The file monitor supports file rotation. To fully work, +rsyslogd must run while the file is rotated. Then, any remaining lines +from the old file are read and processed and when done with that, the +new file is being processed from the beginning. If rsyslogd is stopped +during rotation, the new file is read, but any not-yet-reported lines +from the previous file can no longer be obtained. + +When rsyslogd is stopped while monitoring a text file, it records the +last processed location and continues to work from there upon restart. +So no data is lost during a restart (except, as noted above, if the file +is rotated just in this very moment). + +Notable Features +================ + +- :ref:`Metadata` +- :ref:`State-Files` +- :ref:`WildCards` +- presentation on `using wildcards with imfile <http://www.slideshare.net/rainergerhards1/using-wildcards-with-rsyslogs-file-monitor-imfile>`_ + + +Configuration +============= + +.. note:: + + Parameter names are case-insensitive. + + +Module Parameters +----------------- + +Mode +^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "inotify", "no", "none" + +.. versionadded:: 8.1.5 + +This specifies if imfile is shall run in inotify ("inotify") or polling +("polling") mode. Traditionally, imfile used polling mode, which is +much more resource-intense (and slower) than inotify mode. It is +suggested that users turn on "polling" mode only if they experience +strange problems in inotify mode. In theory, there should never be a +reason to enable "polling" mode and later versions will most probably +remove it. + +Note: if a legacy "$ModLoad" statement is used, the default is *polling*. +This default was kept to prevent problems with old configurations. It +might change in the future. + +.. versionadded:: 8.32.0 + +On Solaris, the FEN API is used instead of INOTIFY. You can set the mode +to fen or inotify (which is automatically mapped to fen on Solaris OS). +Please note that the FEN is limited compared to INOTIFY. Deep wildcard +matches may not work because of the API limits for now. + + +readTimeout +^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "none" + +*Default: 0 (no timeout)* + +.. versionadded:: 8.23.0 + +This sets the default value for input *timeout* parameters. See there +for exact meaning. Parameter value is the number of seconds. + + +timeoutGranularity +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "1", "no", "none" + +.. versionadded:: 8.23.0 + +This sets the interval in which multi-line-read timeouts are checked. +The interval is specified in seconds. Note that +this establishes a lower limit on the length of the timeout. For example, if +a timeoutGranularity of 60 seconds is selected and a readTimeout value of 10 seconds +is used, the timeout is nevertheless only checked every 60 seconds (if there is +no other activity in imfile). This means that the readTimeout is also only +checked every 60 seconds, which in turn means a timeout can occur only after 60 +seconds. + +Note that timeGranularity has some performance implication. The more frequently +timeout processing is triggered, the more processing time is needed. This +effect should be negligible, except if a very large number of files is being +monitored. + + +sortFiles +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +.. versionadded:: 8.32.0 + +If this parameter is set to on, the files will be processed in sorted order, else +not. However, due to the inherent asynchronicity of the whole operations involved +in tracking files, it is not possible to guarantee this sorted order, as it also +depends on operation mode and OS timing. + + +PollingInterval +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "10", "no", "none" + +This setting specifies how often files are to be +polled for new data. For obvious reasons, it has effect only if +imfile is running in polling mode. +The time specified is in seconds. During each +polling interval, all files are processed in a round-robin fashion. + +A short poll interval provides more rapid message forwarding, but +requires more system resources. While it is possible, we strongly +recommend not to set the polling interval to 0 seconds. That will +make rsyslogd become a CPU hog, taking up considerable resources. It +is supported, however, for the few very unusual situations where this +level may be needed. Even if you need quick response, 1 seconds +should be well enough. Please note that imfile keeps reading files as +long as there is any data in them. So a "polling sleep" will only +happen when nothing is left to be processed. + +**We recommend to use inotify mode.** + + +statefile.directory +^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "global(WorkDirectory) value", "no", "none" + +.. versionadded:: 8.1905.0 + +This parameter permits to specify a dedicated directory for the storage of +imfile state files. An absolute path name should be specified (e.g. +`/var/rsyslog/imfilestate`). This permits to keep imfile state files separate +from other rsyslog work items. + +If not specified the global `workDirectory` setting is used. + +**Important: The directory must exist before rsyslog is started.** Also, +rsyslog needs write permissions to work correctly. Keep in mind that this +also might require SELinux definitions (or similar for other enhanced security +systems). + + +Input Parameters +---------------- + +File +^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "yes", "``$InputFileName``" + +The file being monitored. So far, this must be an absolute name (no +macros or templates). Note that wildcards are supported at the file +name level (see **WildCards** below for more details). + + +Tag +^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "yes", "``$InputFileTag``" + +The tag to be assigned to messages read from this file. If you would like to +see the colon after the tag, you need to include it when you assign a tag +value, like so: ``tag="myTagValue:"``. + + +Facility +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer or string (preferred)", "local0", "no", "``$InputFileFacility``" + +The syslog facility to be assigned to messages read from this file. Can be +specified in textual form (e.g. ``local0``, ``local1``, ...) or as numbers (e.g. +16 for ``local0``). Textual form is suggested. Default is ``local0``. + +.. seealso:: + + https://en.wikipedia.org/wiki/Syslog + + +Severity +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer or string (preferred)", "notice", "no", "``$InputFileSeverity``" + +The syslog severity to be assigned to lines read. Can be specified +in textual form (e.g. ``info``, ``warning``, ...) or as numbers (e.g. 6 +for ``info``). Textual form is suggested. Default is ``notice``. + +.. seealso:: + + https://en.wikipedia.org/wiki/Syslog + + +PersistStateInterval +^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "``$InputFilePersistStateInterval``" + +Specifies how often the state file shall be written when processing +the input file. The **default** value is 0, which means a new state +file is at least being written when the monitored files is being closed (end of +rsyslogd execution). Any other value n means that the state file is +written at least every time n file lines have been processed. This setting can +be used to guard against message duplication due to fatal errors +(like power fail). Note that this setting affects imfile performance, +especially when set to a low value. Frequently writing the state file +is very time consuming. + +Note further that rsyslog may write state files +more frequently. This happens if rsyslog has some reason to do so. +There is intentionally no more precise description of when state files +are being written, as this is an implementation detail and may change +as needed. + +**Note: If this parameter is not set, state files are not created.** + + +startmsg.regex +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +.. versionadded:: 8.10.0 + +This permits the processing of multi-line messages. When set, a +messages is terminated when the next one begins, and +``startmsg.regex`` contains the regex that identifies the start +of a message. As this parameter is using regular expressions, it +is more flexible than ``readMode`` but at the cost of lower +performance. +Note that ``readMode`` and ``startmsg.regex`` and ``endmsg.regex`` cannot all be +defined for the same input. + + +endmsg.regex +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +.. versionadded:: 8.38.0 + +This permits the processing of multi-line messages. When set, a message is +terminated when ``endmsg.regex`` matches the line that +identifies the end of a message. As this parameter is using regular +expressions, it is more flexible than ``readMode`` but at the cost of lower +performance. +Note that ``readMode`` and ``startmsg.regex`` and ``endmsg.regex`` cannot all be +defined for the same input. +The primary use case for this is multiline container log files which look like +this: + +.. code-block:: none + + date stdout P start of message + date stdout P middle of message + date stdout F end of message + +The `F` means this is the line which contains the final part of the message. +The fully assembled message should be `start of message middle of message end of +message`. `endmsg.regex="^[^ ]+ stdout F "` will match. + +readTimeout +^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "none" + +.. versionadded:: 8.23.0 + +This can be used with *startmsg.regex* (but not *readMode*). If specified, +partial multi-line reads are timed out after the specified timeout interval. +That means the current message fragment is being processed and the next +message fragment arriving is treated as a completely new message. The +typical use case for this parameter is a file that is infrequently being +written. In such cases, the next message arrives relatively late, maybe hours +later. Specifying a readTimeout will ensure that those "last messages" are +emitted in a timely manner. In this use case, the "partial" messages being +processed are actually full messages, so everything is fully correct. + +To guard against accidental too-early emission of a (partial) message, the +timeout should be sufficiently large (5 to 10 seconds or more recommended). +Specifying a value of zero turns off timeout processing. Also note the +relationship to the *timeoutGranularity* global parameter, which sets the +lower bound of *readTimeout*. + +Setting timeout values slightly increases processing time requirements; the +effect should only be visible of a very large number of files is being +monitored. + + +readMode +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "``$InputFileReadMode``" + +This provides support for processing some standard types of multiline +messages. It is less flexible than ``startmsg.regex`` or ``endmsg.regex`` but +offers higher performance than regex processing. Note that ``readMode`` and +``startmsg.regex`` and ``endmsg.regex`` cannot all be defined for the same +input. + +The value can range from 0-2 and determines the multiline +detection method. + +0 - (**default**) line based (each line is a new message) + +1 - paragraph (There is a blank line between log messages) + +2 - indented (new log messages start at the beginning of a line. If a +line starts with a space or tab "\t" it is part of the log message before it) + + +escapeLF +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "1", "no", "none" + +This is only meaningful if multi-line messages are to be processed. +LF characters embedded into syslog messages cause a lot of trouble, +as most tools and even the legacy syslog TCP protocol do not expect +these. If set to "on", this option avoid this trouble by properly +escaping LF characters to the 4-byte sequence "#012". This is +consistent with other rsyslog control character escaping. By default, +escaping is turned on. If you turn it off, make sure you test very +carefully with all associated tools. Please note that if you intend +to use plain TCP syslog with embedded LF characters, you need to +enable octet-counted framing. For more details, see +`Rainer Gerhards' blog posting on imfile LF escaping <https://rainer.gerhards.net/2013/09/imfile-multi-line-messages.html>`_. + + +escapeLF.replacement +^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "depending on use", "no", "none" + +.. versionadded:: 8.2001.0 + +This parameter works in conjunction with `escapeLF`. It is only +honored if `escapeLF="on"`. + +It permits to replace the default escape sequence by a different character +sequence. The default historically is inconsistent and denpends on which +functionality is used to read the file. It can be either "#012" or "\\n". If +you want to retain that default, do not configure this parameter. + +If it is configured, any sequence may be used. For example, to replace a LF +with a simple space, use:: + + escapeLF.replacement=" " + +It is also possible to configure longer replacements. An example for this is:: + + escapeLF.replacement="[LF]" + +Finally, it is possible to completely remove the LF. This is done by specifying +an empty replacement sequence:: + + escapeLF.replacement="" + + +MaxLinesAtOnce +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "``$InputFileMaxLinesAtOnce``" + +This is a legacy setting that only is supported in *polling* mode. +In *inotify* mode, it is fixed at 0 and all attempts to configure +a different value will be ignored, but will generate an error +message. + +Please note that future versions of imfile may not support this +parameter at all. So it is suggested to not use it. + +In *polling* mode, if set to 0, each file will be fully processed and +then processing switches to the next file. If it is set to any other +value, a maximum of [number] lines is processed in sequence for each file, +and then the file is switched. This provides a kind of multiplexing +the load of multiple files and probably leads to a more natural +distribution of events when multiple busy files are monitored. For +*polling* mode, the **default** is 10240. + + +MaxSubmitAtOnce +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "1024", "no", "none" + +This is an expert option. It can be used to set the maximum input +batch size that imfile can generate. The **default** is 1024, which +is suitable for a wide range of applications. Be sure to understand +rsyslog message batch processing before you modify this option. If +you do not know what this doc here talks about, this is a good +indication that you should NOT modify the default. + + +deleteStateOnFileDelete +^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "none" + +This parameter controls if state files are deleted if their associated +main file is deleted. Usually, this is a good idea, because otherwise +problems would occur if a new file with the same name is created. In +that case, imfile would pick up reading from the last position in +the **deleted** file, which usually is not what you want. + +However, there is one situation where not deleting associated state +file makes sense: this is the case if a monitored file is modified +with an editor (like vi or gedit). Most editors write out modifications +by deleting the old file and creating a new now. If the state file +would be deleted in that case, all of the file would be reprocessed, +something that's probably not intended in most case. As a side-note, +it is strongly suggested *not* to modify monitored files with +editors. In any case, in such a situation, it makes sense to +disable state file deletion. That also applies to similar use +cases. + +In general, this parameter should only by set if the users +knows exactly why this is required. + + +Ruleset +^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "``$InputFileBindRuleset``" + +Binds the listener to a specific :doc:`ruleset <../../concepts/multi_ruleset>`. + + +addMetadata +^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "-1", "no", "none" + +**Default: see intro section on Metadata** + +This is used to turn on or off the addition of metadata to the +message object. + + +addCeeTag +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +This is used to turn on or off the addition of the "@cee:" cookie to the +message object. + + +reopenOnTruncate +^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +This is an **experimental** feature that tells rsyslog to reopen input file +when it was truncated (inode unchanged but file size on disk is less than +current offset in memory). + + +MaxLinesPerMinute +^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "none" + +Instructs rsyslog to enqueue up to the specified maximum number of lines +as messages per minute. Lines above this value are discarded. + +The **default** value is 0, which means that no lines are discarded. + + +MaxBytesPerMinute +^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "none" + +Instructs rsyslog to enqueue a maximum number of bytes as messages per +minute. Once MaxBytesPerMinute is reached, subsequent messages are +discarded. + +Note that messages are not truncated as a result of MaxBytesPerMinute, +rather the entire message is discarded if part of it would be above the +specified maximum bytes per minute. + +The **default** value is 0, which means that no messages are discarded. + + +trimLineOverBytes +^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "none" + +This is used to tell rsyslog to truncate the line which length is greater +than specified bytes. If it is positive number, rsyslog truncate the line +at specified bytes. Default value of 'trimLineOverBytes' is 0, means never +truncate line. + +This option can be used when ``readMode`` is 0 or 2. + + +freshStartTail +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +This is used to tell rsyslog to seek to the end/tail of input files +(discard old logs) **at its first start(freshStart)** and process only new +log messages. + +When deploy rsyslog to a large number of servers, we may only care about +new log messages generated after the deployment. set **freshstartTail** +to **on** will discard old logs. Otherwise, there may be vast useless +message burst on the remote central log receiver + +This parameter only applies to files that are already existing during +rsyslog's initial processing of the file monitors. + +.. warning:: + + Depending on the number and location of existing files, this initial + startup processing may take some time as well. If another process + creates a new file at exactly the time of startup processing and writes + data to it, rsyslog might detect this file and it's data as prexisting + and may skip it. This race is inevitable. So when freshStartTail is used, + some risk of data loss exists. The same holds true if between the last + shutdown of rsyslog and its restart log file content has been added. + As such, the rsyslog team advises against activating the freshStartTail + option. + + +discardTruncatedMsg +^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +When messages are too long they are truncated and the following part is +processed as a new message. When this parameter is turned on the +truncated part is not processed but discarded. + + +msgDiscardingError +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "none" + +Upon truncation an error is given. When this parameter is turned off, no +error will be shown upon truncation. + + +needParse +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +.. versionadded:: 8.1903.0 + +By default, read message are sent to output modules without passing through +parsers. This parameter informs rsyslog to use also defined parser module(s). + + + +persistStateAfterSubmission +^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +.. versionadded:: 8.2006.0 + +This setting makes imfile persist state file information after a batch of +messages has been submitted. It can be activated (switched to "on") in order +to provide enhanced robustness against unclean shutdowns. Depending on the +configuration of the rest of rsyslog (most importantly queues), persisting +the state file after each message submission prevents message loss +when reading files and the system is shutdown in an unclean way (e.g. +loss of power). + +Please note that this setting may cause frequent state file writes and +as such may cause some performance degradation. + + +ignoreOlderThan +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "none" + +.. versionadded:: 8.2108.0 + +Instructs imfile to ignore a discovered file that has not been modified in the +specified number of seconds. Once a file is discovered, the file is no longer +ignored and new data will be read. This option is disabled (set to 0) by default. + + + +.. _Metadata: + +Metadata +======== +The imfile module supports message metadata. It supports the following +data items: + +- filename + + Name of the file where the message originated from. This is most + useful when using wildcards inside file monitors, because it then + is the only way to know which file the message originated from. + The value can be accessed using the %$!metadata!filename% property. + **Note**: For symlink-ed files this does **not** contain name of the + actual file (source of the data) but name of the symlink (file which + matched configured input). + +- fileoffset + + Offset of the file in bytes at the time the message was read. The + offset reported is from the **start** of the line. + This information can be useful when recreating multi-line files + that may have been accessed or transmitted non-sequentially. + The value can be accessed using the %$!metadata!fileoffset% property. + +Metadata is only present if enabled. By default it is enabled for +input() statements that contain wildcards. For all others, it is +disabled by default. It can explicitly be turned on or off via the +*addMetadata* input() parameter, which always overrides the default. + + +.. _State-Files: + +State Files +=========== +Rsyslog must keep track of which parts of the monitored file +are already processed. This is done in so-called "state files" that +are created in the rsyslog working directory and are read on startup to +resume monitoring after a shutdown. The location of the rsyslog +working directory is configurable via the ``global(workDirectory)`` +|FmtAdvancedName| format parameter. + +**Note**: The ``PersistStateInterval`` parameter must be set, otherwise state +files will NOT be created. + +Rsyslog automatically generates state file names. These state file +names will begin with the string ``imfile-state:`` and be followed +by some suffix rsyslog generates. + +There is intentionally no more precise description of when state file +naming, as this is an implementation detail and may change as needed. + +Note that it is possible to set a fixed state file name via the +deprecated ``stateFile`` parameter. It is suggested to avoid this, as +the user must take care of name clashes. Most importantly, if +"stateFile" is set for file monitors with wildcards, the **same** +state file is used for all occurrences of these files. In short, +this will usually not work and cause confusion. Upon startup, +rsyslog tries to detect these cases and emit warning messages. +However, the detection simply checks for the presence of "*" +and as such it will not cover more complex cases. + +Note that when the ``global(workDirectory)`` |FmtAdvancedName| format +parameter is points to a non-writable location, the state file +**will not be generated**. In those cases, the file content will always +be completely re-sent by imfile, because the module does not know that it +already processed parts of that file. if The parameter is not set to all, it +defaults to the file system root, which may or may not be writable by +the rsyslog process. + + +.. _WildCards: + +WildCards +========= + +**Before Version: 8.25.0** + Wildcards are only supported in the filename part, not in directory names. + +* /var/log/\*.log **works**. * +* /var/log/\*/syslog.log does **not work**. * + + +**Since Version: 8.25.0** + Wildcards are supported in filename and paths which means these samples will work: + +* /var/log/\*.log **works**. * +* /var/log/\*/syslog.log **works**. * +* /var/log/\*/\*.log **works**. * + + + All matching files in all matching subfolders will work. + Note that this may decrease performance in imfile depending on how + many directories and files are being watched dynamically. + + + + +Caveats/Known Bugs +================== + +* symlink may not always be properly processed + +Configuration Examples +====================== + +The following sample monitors two files. If you need just one, remove +the second one. If you need more, add them according to the sample ;). +This code must be placed in /etc/rsyslog.conf (or wherever your distro +puts rsyslog's config files). Note that only commands actually needed +need to be specified. The second file uses less commands and uses +defaults instead. + +.. code-block:: none + + module(load="imfile" PollingInterval="10") #needs to be done just once + + # File 1 + input(type="imfile" + File="/path/to/file1" + Tag="tag1" + Severity="error" + Facility="local7") + + # File 2 + input(type="imfile" + File="/path/to/file2" + Tag="tag2") + + # ... and so on ... # + + +Deprecated parameters +===================== + +**Note:** While these parameters are still accepted, they should no longer be +used for newly created configurations. + +stateFile +--------- + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "``$InputFileStateFile``" + +This is the name of this file's state file. This parameter should +usually **not** be used. Check the section on "State Files" above +for more details. + + diff --git a/source/configuration/modules/imgssapi.rst b/source/configuration/modules/imgssapi.rst new file mode 100644 index 0000000..de51b36 --- /dev/null +++ b/source/configuration/modules/imgssapi.rst @@ -0,0 +1,154 @@ +************************************ +imgssapi: GSSAPI Syslog Input Module +************************************ + +=========================== =========================================================================== +**Module Name:** **imgssapi** +**Author:** varmojfekoj +=========================== =========================================================================== + + +Purpose +======= + +Provides the ability to receive syslog messages from the network +protected via Kerberos 5 encryption and authentication. This module also +accept plain tcp syslog messages on the same port if configured to do +so. If you need just plain tcp, use :doc:`imtcp <imtcp>` instead. + +Note: This is a contributed module, which is not supported by the +rsyslog team. We recommend to use RFC5425 TLS-protected syslog +instead. + +.. toctree:: + :maxdepth: 1 + + gssapi + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + + +Input Parameter +--------------- + +.. note:: + + Parameter are only available in Legacy Format. + + +InputGSSServerRun +^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "``$InputGSSServerRun``" + +Starts a GSSAPI server on selected port - note that this runs +independently from the TCP server. + + +InputGSSServerServiceName +^^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "``$InputGSSServerServiceName``" + +The service name to use for the GSS server. + + +InputGSSServerPermitPlainTCP +^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "0", "no", "``$InputGSSServerPermitPlainTCP``" + +Permits the server to receive plain tcp syslog (without GSS) on the +same port. + + +InputGSSServerMaxSessions +^^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "200", "no", "``$InputGSSServerMaxSessions``" + +Sets the maximum number of sessions supported. + + +InputGSSServerKeepAlive +^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "0", "no", "``$InputGSSServerKeepAlive``" + +.. versionadded:: 8.5.0 + +Enables or disable keep-alive handling. + + +InputGSSListenPortFileName +^^^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "``$InputGSSListenPortFileName``" + +.. versionadded:: 8.38.0 + +With this parameter you can specify the name for a file. In this file the +port, imtcp is connected to, will be written. +This parameter was introduced because the testbench works with dynamic ports. + +.. note:: + + If this parameter is set, 0 will be accepted as the port. Otherwise it + is automatically changed to port 514 + + +Caveats/Known Bugs +================== + +- module always binds to all interfaces +- only a single listener can be bound + +Example +======= + +This sets up a GSS server on port 1514 that also permits to receive +plain tcp syslog messages (on the same port): + +.. code-block:: none + + $ModLoad imgssapi # needs to be done just once + $InputGSSServerRun 1514 + $InputGSSServerPermitPlainTCP on + + diff --git a/source/configuration/modules/imhiredis.rst b/source/configuration/modules/imhiredis.rst new file mode 100644 index 0000000..3574332 --- /dev/null +++ b/source/configuration/modules/imhiredis.rst @@ -0,0 +1,356 @@ + +.. include:: <isonum.txt> + +***************************** +Imhiredis: Redis input plugin +***************************** + +==================== ===================================== +**Module Name:** **imhiredis** +**Author:** Jeremie Jourdin <jeremie.jourdin@advens.fr> +**Contributors:** Theo Bertin <theo.bertin@advens.fr> +==================== ===================================== + +Purpose +======= + +Imhiredis is an input module reading arbitrary entries from Redis. +It uses the `hiredis library <https://github.com/redis/hiredis.git>`_ to query Redis instances using 3 modes: + +- **queues**, using `LIST <https://redis.io/commands#list>`_ commands +- **channels**, using `SUBSCRIBE <https://redis.io/commands#pubsub>`_ commands +- **streams**, using `XREAD/XREADGROUP <https://redis.io/commands/?group=stream>`_ commands + + +.. _imhiredis_queue_mode: + +Queue mode +---------- + +The **queue mode** uses Redis LISTs to push/pop messages to/from lists. It allows simple and efficient uses of Redis as a queueing system, providing both LIFO and FIFO methods. + +This mode should be preferred if the user wants to use Redis as a caching system, with one (or many) Rsyslog instances POP'ing out entries. + +.. Warning:: + This mode was configured to provide optimal performances while not straining Redis, but as imhiredis has to poll the instance some trade-offs had to be made: + + - imhiredis POPs entries by batches of 10 to improve performances (size of batch is configurable via the batchsize parameter) + - when no entries are left in the list, the module sleeps for 1 second before checking the list again. This means messages might be delayed by as much as 1 second between a push to the list and a pop by imhiredis (entries will still be POP'ed out as fast as possible while the list is not empty) + + +.. _imhiredis_channel_mode: + +Channel mode +------------ + +The **subscribe** mode uses Redis PUB/SUB system to listen to messages published to Redis' channels. It allows performant use of Redis as a message broker. + +This mode should be preferred to use Redis as a message broker, with zero, one or many subscribers listening to new messages. + +.. Warning:: + This mode shouldn't be used if messages are to be reliably processed, as messages published when no Imhiredis is listening will result in the loss of the message. + + +.. _imhiredis_stream_mode: + +Stream mode +------------ + +The **stream** mode uses `Redis Streams system <https://redis.io/docs/data-types/streams/>`_ to read entries published to Redis' streams. It is a good alternative when: + - sharing work is desired + - not losing any log (even in the case of a crash) is mandatory + +This mode is especially useful to define pools of workers that do various processing along the way, while ensuring not a single log is lost during processing by a worker. + +.. note:: + As Redis streams do not insert simple values in keys, but rather fleid/value pairs, this mode can also be useful when handling structured data. This is better shown with the examples for the parameter :ref:`imhiredis_fields`. + + This mode also adds additional internal metadata to the message, it won't be included in json data or regular fields, but + + - **$.redis!stream** will be added to the message, with the value of the source stream + - **$.redis!index** will be added to the message, with the exact ID of the entry + - **$.redis!group** will be added in the message (if :ref:`imhiredis_stream_consumergroup` is set), with the value of the group used to read the entry + - **$.redis!consumer** will be added in the message (if :ref:`imhiredis_stream_consumername` is set), with the value of the consumer name used to read the entry + + This is especially useful when used with the omhiredis module, to allow it to get the required information semi-automatically (custom templates will still be required in the user configuration) + +.. Warning:: + This mode is the most reliable to handle entries stored in Redis, but it might also be the one with the most overhead. Although still minimal, make sure to test the different options and determine if this mode is right for you! + + +Master/Replica +-------------- + +This module is able to automatically connect to the master instance of a master/replica(s) cluster. Simply providing a valid connection entry point (being the current master or a valid replica), Imhiredis is able to redirect to the master node on startup and when states change between nodes. + + +Configuration Parameters +======================== + +.. note:: + Parameter names are case-insensitive + + +Input Parameters +---------------- + +.. _imhiredis_mode: + +mode +^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "subscribe", "yes", "none" + +| Defines the mode to use for the module. +| Should be either "**subscribe**" (:ref:`imhiredis_channel_mode`), "**queue**" (:ref:`imhiredis_queue_mode`) or "**stream**" (:ref:`imhiredis_stream_mode`) (case-sensitive). + + +ruleset +^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +Assign messages from this input to a specific Rsyslog ruleset. + + +batchsize +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "number", "10", "yes", "none" + +Defines the dequeue batch size for redis pipelining. +imhiredis will read "**batchsize**" elements from redis at a time. + +When using the :ref:`imhiredis_queue_mode`, defines the size of the batch to use with LPOP / RPOP. + + +.. _imhiredis_key: + +key +^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "yes", "none" + +Defines either the name of the list to use (for :ref:`imhiredis_queue_mode`) or the channel to listen to (for :ref:`imhiredis_channel_mode`). + + +.. _imhiredis_socketPath: + +socketPath +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "no", "if no :ref:`imhiredis_server` provided", "none" + +Defines the socket to use when trying to connect to Redis. Will be ignored if both :ref:`imhiredis_server` and :ref:`imhiredis_socketPath` are given. + + +.. _imhiredis_server: + +server +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "ip", "127.0.0.1", "if no :ref:`imhiredis_socketPath` provided", "none" + +The Redis server's IP to connect to. + + +.. _imhiredis_port: + +port +^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "number", "6379", "no", "none" + +The Redis server's port to use when connecting via IP. + + +.. _imhiredis_password: + +password +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +The password to use when connecting to a Redis node, if necessary. + + +.. _imhiredis_uselpop: + +uselpop +^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "boolean", "no", "no", "none" + +| When using the :ref:`imhiredis_queue_mode`, defines if imhiredis should use a LPOP instruction instead of a RPOP (the default). +| Has no influence on the :ref:`imhiredis_channel_mode` and will be ignored if set with this mode. + + +.. _imhiredis_stream_consumergroup: + +stream.consumerGroup +^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "", "no", "none" + +| When using the :ref:`imhiredis_stream_mode`, defines a consumer group name to use (see `the XREADGROUP documentation <https://redis.io/commands/xreadgroup/>`_ for details). This parameter activates the use of **XREADGROUP** commands, in replacement to simple XREADs. +| Has no influence in the other modes (queue or channel) and will be ignored. + +.. note:: + If this parameter is set, :ref:`imhiredis_stream_consumername` should also be set + + +.. _imhiredis_stream_consumername: + +stream.consumerName +^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "", "no", "none" + +| When using the :ref:`imhiredis_stream_mode`, defines a consumer name to use (see `the XREADGROUP documentation <https://redis.io/commands/xreadgroup/>`_ for details). This parameter activates the use of **XREADGROUP** commands, in replacement to simple XREADs. +| Has no influence in the other modes (queue or channel) and will be ignored. + +.. note:: + If this parameter is set, :ref:`imhiredis_stream_consumergroup` should also be set + + +.. _imhiredis_stream_readfrom: + +stream.readFrom +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "$", "no", "none" + +| When using the :ref:`imhiredis_stream_mode`, defines the `starting ID <https://redis.io/docs/data-types/streams-tutorial/#entry-ids>`_ for XREAD/XREADGROUP commands (can also use special IDs, see `documentation <https://redis.io/docs/data-types/streams-tutorial/#special-ids-in-the-streams-api>`_). +| Has no influence in the other modes (queue or channel) and will be ignored. + + +.. _imhiredis_stream_consumerack: + +stream.consumerACK +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "boolean", "on", "no", "none" + +| When using :ref:`imhiredis_stream_mode` with :ref:`imhiredis_stream_consumergroup` and :ref:`imhiredis_stream_consumername`, determines if the module should directly acknowledge the ID once read from the Consumer Group. +| Has no influence in the other modes (queue or channel) and will be ignored. + +.. note:: + When using Consumer Groups and imhiredis, omhiredis can also integrate with this workflow to acknowledge a processed message once put back in another stream (or somewhere else). This parameter is then useful set to **off** to let the omhiredis module acknowledge the input ID once the message is correctly sent. + + +.. _imhiredis_stream_autoclaimidletime: + +stream.autoclaimIdleTime +^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "positive number", "0", "no", "none" + +| When using :ref:`imhiredis_stream_mode` with :ref:`imhiredis_stream_consumergroup` and :ref:`imhiredis_stream_consumername`, determines if the module should check for pending IDs that exceed this time (**in milliseconds**) to assume the original consumer failed to acknowledge the log and claim them for their own (see `the redis ducumentation <https://redis.io/docs/data-types/streams-tutorial/#automatic-claiming>`_ on this subject for more details on how that works). +| Has no influence in the other modes (queue or channel) and will be ignored. + +.. note:: + If this parameter is set, the AUTOCLAIM operation will also take into account the specified :ref:`imhiredis_stream_readfrom` parameter. **If its value is '$' (default), the AUTOCLAIM commands will use '0-0' as the starting ID**. + + + +.. _imhiredis_fields: + +fields +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "array", "[]", "no", "none" + +| When using :ref:`imhiredis_stream_mode`, the module won't get a simple entry but will instead get hashes, with field/value pairs. +| By default, the module will insert every value into their respective field in the **$!** object, but this parameter can change this behaviour, for each entry the value will be a string where: + + - if the entry begins with a **!** or a **.**, it will be taken as a key to take into the original entry + - if the entry doesn't begin with a **!** or a **.**, the value will be taken verbatim + - in addition, if the value is prefixed with a **:<key>:** pattern, the value (verbatim or taken from the entry) will be inserted in this specific key (or subkey) + +*Examples*: + +.. csv-table:: + :header: "configuration", "result" + :widths: auto + :class: parameter-table + + ``["static_value"]``, the value "static_value" will be inserted in $!static_value + ``[":key:static_value"]``, the value "static_value" will be inserted in $!key + ``["!field"]``, the value of the field "field" will be inserted in $!field + ``[":key!subkey:!field"]``, the value of the field "field" will be inserted in $!key!subkey + diff --git a/source/configuration/modules/imhttp.rst b/source/configuration/modules/imhttp.rst new file mode 100644 index 0000000..1200c39 --- /dev/null +++ b/source/configuration/modules/imhttp.rst @@ -0,0 +1,369 @@ +************************* +imhttp: http input module +************************* + +=========================== =========== +**Module Name:** **imhttp** +**Author:** Nelson Yen +=========================== =========== + + +Purpose +======= + +Provides the ability to receive adhoc and plaintext syslog messages via http. The format of messages accepted, +depends on configuration. imhttp exposes the capabilities and the underlying options of the http library +used, which currently is civetweb. + +Civetweb documentation: + +- `Civetweb User Manual <https://github.com/civetweb/civetweb/blob/master/docs/UserManual.md>`_ +- `Civetweb Configuration Options <https://github.com/civetweb/civetweb/blob/master/docs/UserManual.md#configuration-options>`_ + +Notable Features +================ + +- :ref:`imhttp-statistic-counter` +- :ref:`imhttp-error-messages` + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + + +Module Parameters +----------------- + +Ports +^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "no", "ports", "8080" + +Configures "listening_ports" in the civetweb library. This option may also be configured using the +liboptions_ (below) however, this option will take precendence. + +- `Civetweb listening_ports <https://github.com/civetweb/civetweb/blob/master/docs/UserManual.md#listening_ports-8080>`_ + + +documentroot +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "no", "none", "." + +Configures "document_root" in the civetweb library. This option may also be configured using liboptions_, however +this option will take precedence. + +- `Civetweb document_root <https://github.com/civetweb/civetweb/blob/master/docs/UserManual.md#document_root->`_ + + +.. _liboptions: + +liboptions +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "no", "none", "none" + +Configures civetweb library "Options". + +- `Civetweb Options <https://github.com/civetweb/civetweb/blob/master/docs/UserManual.md#options-from-civetwebc>`_ + + +Input Parameters +---------------- + +These parameters can be used with the "input()" statement. They apply to +the input they are specified with. + + +Endpoint +^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "yes", "path that begins with '/' ", "none" + +Sets a request path for an http input. Path should always start with a '/'. + + +DisableLFDelimiter +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "binary", "no", "", "off" + +By default LF is used to delimit msg frames, for data is sent in batches. +Set this to ‘on’ if this behavior is not needed. + + +Name +^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "no", "", "imhttp" + +Sets a name for the inputname property. If no name is set "imhttp" +is used by default. Setting a name is not strictly necessary, but can +be useful to apply filtering based on which input the message was +received from. + + +Ruleset +^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "no", "", "default ruleset" + +Binds specified ruleset to this input. If not set, the default +ruleset is bound. + + +SupportOctetCountedFraming +^^^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "binary", "no", "", "off" + +Useful to send data using syslog style message framing, disabled by default. Message framing is described by `RFC 6587 <https://tools.ietf.org/html/rfc6587#section-3.4.1>`_ . + + +RateLimit.Interval +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "integer", "no", "none", "0" + +Specifies the rate-limiting interval in seconds. Set it to a number +of seconds to activate rate-limiting. + + +RateLimit.Burst +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "integer", "no", "none", "10000" + +Specifies the rate-limiting burst in number of messages. + + + +flowControl +^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "binary", "no", "none", "on" + +Flow control is used to throttle the sender if the receiver queue is +near-full preserving some space for input that can not be throttled. + + + +addmetadata +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "binary", "no", "none", "off" + +Enables metadata injection into `$!metadata` property. Currently, only header data is supported. +The following metadata will be injected into the following properties: + +- `$!metadata!httpheaders`: http header data will be injected here as key-value pairs. All header names will automatically be lowercased + for case-insensitive access. + +- `$!metadata!queryparams`: query parameters from the http request will be injected here as key-value pairs. All header names will automatically be lowercased + for case-insensitive access. + + +basicAuthFile +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "no", "none", "" + +Enables access control to this endpoint using http basic authentication. Option is disabled by default. +To enable it, set this option to a `htpasswd file`, which can be generated using a standard `htpasswd` tool. + +See also: + +- `HTTP Authorization <https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Authorization>`_ +- `HTTP Basic Authentication <https://developer.mozilla.org/en-US/docs/Web/HTTP/Authentication#basic_authentication_scheme>`_ +- `htpasswd utility <https://httpd.apache.org/docs/2.4/programs/htpasswd.html>`_ + + +.. _imhttp-statistic-counter: + + +basicAuthFile +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "no", "none", "none" + +Configures a `htpasswd <https://httpd.apache.org/docs/2.4/programs/htpasswd.html>`_ file and enables `basic authentication <https://en.wikipedia.org/wiki/Basic_access_authentication>`_ on http request received on this input. +If this option is not set, basic authentation will not be enabled. + + +Statistic Counter +================= + +This plugin maintains global imhttp :doc:`statistics <../rsyslog_statistic_counter>`. The statistic's origin and name is "imhttp" and is +accumulated for all inputs. The statistic has the following counters: + + +- **submitted** - Total number of messages successfully submitted for processing since startup. +- **failed** - Total number of messages failed since startup, due to processing a request. +- **discarded** - Total number of messages discarded since startup, due to rate limiting or similar. + + +.. _imhttp-error-messages: + +Error Messages +============== + +When a message is to long it will be truncated and an error will show the remaining length of the message and the beginning of it. It will be easier to comprehend the truncation. + + +Caveats/Known Bugs +================== + +- module currently only a single http instance, however multiple ports may be bound. + + +Examples +======== + +Example 1 +--------- + +This sets up a http server instance on port 8080 with two inputs. +One input path at '/postrequest', and another at '/postrequest2': + +.. code-block:: none + + # ports=8080 + # document root='.' + module(load="imhttp") # needs to be done just once + + # Input using default LF delimited framing + # For example, the following http request, with data body "Msg0001\nMsg0002\nMsg0003" + ## + # - curl -si http://localhost:$IMHTTP_PORT/postrequest -d $'Msg0001\nMsg0002\nMsg0003' + ## + # Results in the 3 message objects being submitted into rsyslog queues. + # - Message object with `msg` property set to `Msg0001` + # - Message object with `msg` property set to `Msg0002` + # - Message object with `msg` property set to `Msg0003` + + input(type="imhttp" + name="myinput1" + endpoint="/postrequest" + ruleset="postrequest_rs") + + # define 2nd input path, using octet-counted framing, + # and routing to different ruleset + input(type="imhttp" + name="myinput2" + endpoint="/postrequest2" + SupportOctetCountedFraming="on" + ruleset="postrequest_rs") + + # handle the messages in ruleset + ruleset(name="postrequest_rs") { + action(type="omfile" file="/var/log/http_messages" template="myformat") + } + + +Example 2 +--------- + +This sets up a http server instance on ports 80 and 443s (use 's' to indicate ssl) with an input path at '/postrequest': + +.. code-block:: none + + # ports=8080, 443 (ssl) + # document root='.' + module(load="imhttp" ports=8080,443s) + input(type="imhttp" + endpoint="/postrequest" + ruleset="postrequest_rs") + + + +Example 3 +--------- + +imhttp can also support the underlying options of `Civetweb <https://github.com/civetweb/civetweb/blob/master/docs/UserManual.md>`_ using the liboptions_ option. + +.. code-block:: none + + module(load="imhttp" + liboptions=[ + "error_log_file=my_log_file_path", + "access_log_file=my_http_access_log_path", + ]) + + input(type="imhttp" + endpoint="/postrequest" + ruleset="postrequest_rs" + ) diff --git a/source/configuration/modules/imjournal.rst b/source/configuration/modules/imjournal.rst new file mode 100644 index 0000000..5c0404c --- /dev/null +++ b/source/configuration/modules/imjournal.rst @@ -0,0 +1,474 @@ +*************************************** +imjournal: Systemd Journal Input Module +*************************************** + +=========================== =========================================================================== +**Module Name:** **imjournal** +**Author:** Jiri Vymazal <jvymazal@redhat.com> (This module is **not** project-supported) +**Available since:** 7.3.11 +=========================== =========================================================================== + + +Purpose +======= + +Provides the ability to import structured log messages from systemd +journal to syslog. + +Note that this module reads the journal database, what is considered a +relatively performance-intense operation. As such, the performance of a +configuration utilizing this module may be notably slower than when +using `imuxsock <imuxsock.html>`_. The journal provides imuxsock with a +copy of all "classical" syslog messages, however, it does not provide +structured data. Only if that structured data is needed, imjournal must be used. +Otherwise, imjournal may simply be replaced by imuxsock, and we highly +suggest doing so. + +We suggest to check out our short presentation on `rsyslog journal +integration <http://youtu.be/GTS7EuSdFKE>`_ to learn more details of +anticipated use cases. + +**Warning:** Some versions of systemd journal have problems with +database corruption, which leads to the journal to return the same data +endlessly in a tight loop. This results in massive message duplication +inside rsyslog probably resulting in a denial-of-service when the system +resources get exhausted. This can be somewhat mitigated by using proper +rate-limiters, but even then there are spikes of old data which are +endlessly repeated. By default, ratelimiting is activated and permits to +process 20,000 messages within 10 minutes, what should be well enough +for most use cases. If insufficient, use the parameters described below +to adjust the permitted volume. **It is strongly recommended to use this +plugin only if there is hard need to do so.** + + +Notable Features +================ + +- statistics counters + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + + +Module Parameters +================= + + +PersistStateInterval +^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "10", "no", "``$imjournalPersistStateInterval``" + +This is a global setting. It specifies how often should the journal +state be persisted. The persists happens after each *number-of-messages*. +This option is useful for rsyslog to start reading from the last journal +message it read. + +FileCreateMode +^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "octalNumber", "0644", "no", "none" + +Set the access permissions for the state file. The value given must +always be a 4-digit octal number, with the initial digit being zero. +Please note that the actual permission depend on rsyslogd's process +umask. If in doubt, use "$umask 0000" right at the beginning of the +configuration file to remove any restrictions. The state file's only +consumer is rsyslog, so it's recommended to adjust the value according +to that. + + +StateFile +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "``$imjournalStateFile``" + +This is a global setting. It specifies where the state file for +persisting journal state is located. If a full path name is given +(starting with "/"), that path is used. Otherwise the given name +is created inside the working directory. + + +Ratelimit.Interval +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "600", "no", "``$imjournalRatelimitInterval``" + +Specifies the interval in seconds onto which rate-limiting is to be +applied. If more than ratelimit.burst messages are read during that +interval, further messages up to the end of the interval are +discarded. The number of messages discarded is emitted at the end of +the interval (if there were any discards). + +**Setting this value to 0 turns off ratelimiting.** + +Note that it is *not recommended to turn off ratelimiting*, +except that you know for +sure journal database entries will never be corrupted. Without +ratelimiting, a corrupted systemd journal database may cause a kind +of denial of service We are stressing this point as multiple users +have reported us such problems with the journal database - in June +of 2013 and occasionally also after this time (up until the time of +this writing in January 2019). + + +Ratelimit.Burst +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "20000", "no", "``$imjournalRatelimitBurst``" + +Specifies the maximum number of messages that can be emitted within +the ratelimit.interval interval. For further information, see +description there. + + +IgnorePreviousMessages +^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "``$ImjournalIgnorePreviousMessages``" + +This option specifies whether imjournal should ignore messages +currently in journal and read only new messages. This option is only +used when there is no StateFile to avoid message loss. + + +DefaultSeverity +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "severity", "5", "no", "``$ImjournalDefaultSeverity``" + +Some messages coming from journald don't have the SYSLOG_PRIORITY +field. These are typically the messages logged through journald's +native API. This option specifies the default severity for these +messages. Can be given either as a name or a number. Defaults to 'notice'. + + +DefaultFacility +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "facility", "LOG_USER", "no", "``$ImjournalDefaultFacility``" + +Some messages coming from journald don't have the SYSLOG_FACILITY +field. These are typically the messages logged through journald's +native API. This option specifies the default facility for these +messages. Can be given either as a name or a number. Defaults to 'user'. + + +UsePidFromSystem +^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "0", "no", "none" + +Retrieves the trusted systemd parameter, _PID, instead of the user +systemd parameter, SYSLOG_PID, which is the default. +This option override the "usepid" option. +This is now deprecated. It is better to use usepid="syslog" instead. + + +UsePid +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "both", "no", "none" + +Sets the PID source from journal. + +*syslog* + *imjournal* retrieves SYSLOG_PID from journal as PID number. + +*system* + *imjournal* retrieves _PID from journal as PID number. + +*both* + *imjournal* trying to retrieve SYSLOG_PID first. When it is not + available, it is also trying to retrieve _PID. When none of them is available, + message is parsed without PID number. + + +IgnoreNonValidStatefile +^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "none" + +When a corrupted statefile is read imjournal ignores the statefile and continues +with logging from the beginning of the journal (from its end if IgnorePreviousMessages +is on). After PersistStateInterval or when rsyslog is stopped invalid statefile +is overwritten with a new valid cursor. + + +WorkAroundJournalBug +^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "none" + +.. versionadded:: 8.37.0 + +**Deprecated.** This option was intended as temporary and has no effect now +(since 8.1910.0). Left for backwards compatibility only. + + +FSync +^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +.. versionadded:: 8.1908.0 + +When there is a hard crash, power loss or similar abrupt end of rsyslog process, +there is a risk of state file not being written to persistent storage or possibly +being corrupted. This then results in imjournal starting reading elsewhere then +desired and most probably message duplication. To mitigate this problem you can +turn this option on which will force state file writes to persistent physical +storage. Please note that fsync calls are costly, so especially with lower +PersistStateInterval value, this may present considerable performance hit. + + +Remote +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +.. versionadded:: 8.1910.0 + +When this option is turned on, imjournal will pull not only all local journal +files (default behavior), but also any journal files on machine originating from +remote sources. + +defaultTag +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +.. versionadded:: 8.2312.0 + +The DefaultTag option specifies the default value for the tag field. +In imjournal, this can happen when one of the following is missing: + +* identifier string provided by the application (SYSLOG_IDENTIFIER) or +* name of the process the journal entry originates from (_COMM) + +Under normal circumstances, at least one of the previously mentioned fields +is always part of the journal message. But there are some corner cases +where this is not the case. This parameter provides the ability to alter +the content of the tag field. + + +Input Module Parameters +======================= + +Parameters specific to the input module. + +Main +^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "journal", "no", "none" + +.. versionadded:: 8.2312.0 + +When this option is turned on within the input module, imjournal will run the +target ruleset in the main thread and will be stop taking input if the output +module is not accepting data. If multiple input moduels set `main` to true, only +the first one will be affected. The non `main` rulesets will run in the +background thread and not affected by the output state. + + + +Statistic Counter +================= + +.. _imjournal-statistic-counter: + +This plugin maintains :doc:`statistics <../rsyslog_statistic_counter>` for each listener and for each worker thread. The listener statistic is named "imjournal". + +The following properties are maintained for each listener: + +- **read** - total number of message read from journal since startup. + +- **submitted** - total number of messages submitted to main queue after reading from journal for processing + since startup. All records may not be submitted due to rate-limiting. + +- **discarded** - total number of messages that were read but not submitted to main queue due to rate-limiting. + +- **failed** - total number of failures to read messages from journal. + +- **poll_failed** - total number of journal poll failures. + +- **rotations** - total number of journal file rotations. + +- **recovery_attempts** - total number of recovery attempts by imjournal after unknown errors by closing and + re-opening journal. + +- **ratelimit_discarded_in_interval** - number of messages discarded due to rate-limiting within configured + rate-limiting interval. + +- **disk_usage_bytes** - total size of journal obtained from sd_journal_get_usage(). + +Here is an example output of corresponding imjournal impstat message, which is produced by loading imjournal +with default rate-limit interval and burst and running a docker container with log-driver as journald that +spews lots of logs to stdout: + +.. code-block:: none + + Jun 13 15:02:48 app1-1.example.com rsyslogd-pstats: imjournal: origin=imjournal submitted=20000 read=216557 + discarded=196557 failed=0 poll_failed=0 rotations=6 recovery_attempts=0 ratelimit_discarded_in_interval=196557 + disk_usage_bytes=106610688 + +Although these counters provide insight into imjournal end message submissions to main queue as well as losses due to +rate-limiting or other problems to extract messages from journal, they don't offer full visibility into journal end +issues. While these counters measure journal rotations and disk usage, they do not offer visibility into message +loss due to journal rate-limiting. sd_journal_* API does not provide any visibility into messages that are +discarded by the journal due to rate-limiting. Journald does emit a syslog message when log messages cannot make +it into the journal due to rate-limiting: + +.. code-block:: none + + Jun 13 15:50:32 app1-1.example.com systemd-journal[333]: Suppressed 102 messages from /system.slice/docker.service + +Such messages can be processed after they are read through imjournal to get a signal for message loss due to journal +end rate-limiting using a dynamic statistics counter for such log lines with a rule like this: + +.. code-block:: none + + dyn_stats(name="journal" resettable="off") + if $programname == 'journal' and $msg contains 'Suppressed' and $msg contains 'messages from' then { + set $.inc = dyn_inc("journal", "suppressed_count"); + } + +Caveats/Known Bugs: +=================== + +- As stated above, a corrupted systemd journal database can cause major + problems, depending on what the corruption results in. This is beyond + the control of the rsyslog team. + +- imjournal does not check if messages received actually originated + from rsyslog itself (via omjournal or other means). Depending on + configuration, this can also lead to a loop. With imuxsock, this + problem does not exist. + + +Build Requirements: +=================== + +Development headers for systemd, version >= 197. + + +Example 1 +========= + +The following example shows pulling structured imjournal messages and +saving them into /var/log/ceelog. + +.. code-block:: none + + module(load="imjournal" PersistStateInterval="100" + StateFile="/path/to/file") #load imjournal module + module(load="mmjsonparse") #load mmjsonparse module for structured logs + + template(name="CEETemplate" type="string" string="%TIMESTAMP% %HOSTNAME% %syslogtag% @cee: %$!all-json%\n" ) #template for messages + + action(type="mmjsonparse") + action(type="omfile" file="/var/log/ceelog" template="CEETemplate") + + +Example 2 +========= + +The following example is the same as `Example 1`, but with the input module. + +.. code-block:: none + + ruleset(name="imjournam-example" queue.type="direct"){ + action(type="mmjsonparse") + action(type="omfile" file="/var/log/ceelog" template="CEETemplate") + } + + input( + type="imjournal" + ruleset="imjournam-example" + main="on" + ) diff --git a/source/configuration/modules/imkafka.rst b/source/configuration/modules/imkafka.rst new file mode 100644 index 0000000..e589b49 --- /dev/null +++ b/source/configuration/modules/imkafka.rst @@ -0,0 +1,177 @@ +******************************* +imkafka: read from Apache Kafka +******************************* + +=========================== =========================================================================== +**Module Name:** **imkafka** +**Author:** Andre Lorbach <alorbach@adiscon.com> +**Available since:** 8.27.0 +=========================== =========================================================================== + + +Purpose +======= + +The imkafka plug-in implements an Apache Kafka consumer, permitting +rsyslog to receive data from Kafka. + + +Configuration Parameters +======================== + +Note that imkafka supports some *Array*-type parameters. While the parameter +name can only be set once, it is possible to set multiple values with that +single parameter. + +For example, to select a broker, you can use + +.. code-block:: none + + input(type="imkafka" topic="mytopic" broker="localhost:9092" consumergroup="default") + +which is equivalent to + +.. code-block:: none + + input(type="imkafka" topic="mytopic" broker=["localhost:9092"] consumergroup="default") + +To specify multiple values, just use the bracket notation and create a +comma-delimited list of values as shown here: + +.. code-block:: none + + input(type="imkafka" topic="mytopic" + broker=["localhost:9092", + "localhost:9093", + "localhost:9094"] + ) + + +.. note:: + + Parameter names are case-insensitive. + + +Module Parameters +----------------- + +Currently none. + + +Action Parameters +----------------- + +Broker +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "array", "localhost:9092", "no", "none" + +Specifies the broker(s) to use. + + +Topic +^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "yes", "none" + +Specifies the topic to produce to. + + +ConfParam +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "array", "none", "no", "none" + +Permits to specify Kafka options. Rather than offering a myriad of +config settings to match the Kafka parameters, we provide this setting +here as a vehicle to set any Kafka parameter. This has the big advantage +that Kafka parameters that come up in new releases can immediately be used. + +Note that we use librdkafka for the Kafka connection, so the parameters +are actually those that librdkafka supports. As of our understanding, this +is a superset of the native Kafka parameters. + + +ConsumerGroup +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +With this parameter the group.id for the consumer is set. All consumers +sharing the same group.id belong to the same group. + + +Ruleset +^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +Specifies the ruleset to be used. + + +ParseHostname +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +.. versionadded:: 8.38.0 + +If this parameter is set to on, imkafka will parse the hostname in log +if it exists. The result can be retrieved from $hostname. If it's off, +for compatibility reasons, the local hostname is used, same as the previous +version. + + +Caveats/Known Bugs +================== + +- currently none + + +Examples +======== + +Example 1 +--------- + +In this sample a consumer for the topic static is created and will forward the messages to the omfile action. + +.. code-block:: none + + module(load="imkafka") + input(type="imkafka" topic="static" broker="localhost:9092" + consumergroup="default" ruleset="pRuleset") + + ruleset(name="pRuleset") { + action(type="omfile" file="path/to/file") + } diff --git a/source/configuration/modules/imklog.rst b/source/configuration/modules/imklog.rst new file mode 100644 index 0000000..2de34ed --- /dev/null +++ b/source/configuration/modules/imklog.rst @@ -0,0 +1,230 @@ +******************************* +imklog: Kernel Log Input Module +******************************* + +=========================== =========================================================================== +**Module Name:** **imklog** +**Author:** `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com> +=========================== =========================================================================== + + +Purpose +======= + +Reads messages from the kernel log and submits them to the syslog +engine. + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + + +Module Parameters +----------------- + +InternalMsgFacility +^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "facility", "(see description)", "no", "``$KLogInternalMsgFacility``" + +The facility which messages internally generated by imklog will +have. imklog generates some messages of itself (e.g. on problems, +startup and shutdown) and these do not stem from the kernel. +Historically, under Linux, these too have "kern" facility. Thus, on +Linux platforms the default is "kern" while on others it is +"syslogd". You usually do not need to specify this configuration +directive - it is included primarily for few limited cases where it +is needed for good reason. Bottom line: if you don't have a good idea +why you should use this setting, do not touch it. + + +PermitNonKernelFacility +^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "``$KLogPermitNonKernelFacility``" + +At least under BSD the kernel log may contain entries with +non-kernel facilities. This setting controls how those are handled. +The default is "off", in which case these messages are ignored. +Switch it to on to submit non-kernel messages to rsyslog processing. + + +ConsoleLogLevel +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "-1", "no", "``$klogConsoleLogLevel``" + +Sets the console log level. If specified, only messages with up to +the specified level are printed to the console. The default is -1, +which means that the current settings are not modified. To get this +behavior, do not specify $klogConsoleLogLevel in the configuration +file. Note that this is a global parameter. Each time it is changed, +the previous definition is re-set. The one activate will be that one +that is active when imklog actually starts processing. In short +words: do not specify this directive more than once! + +**Linux only**, ignored on other platforms (but may be specified) + + +ParseKernelTimestamp +^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "``$klogParseKernelTimestamp``" + +If enabled and the kernel creates a timestamp for its log messages, +this timestamp will be parsed and converted into regular message time +instead to use the receive time of the kernel message (as in 5.8.x +and before). Default is 'off' to prevent parsing the kernel timestamp, +because the clock used by the kernel to create the timestamps is not +supposed to be as accurate as the monotonic clock required to convert +it. Depending on the hardware and kernel, it can result in message +time differences between kernel and system messages which occurred at +same time. + + +KeepKernelTimestamp +^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "``$klogKeepKernelTimestamp``" + +If enabled, this option causes to keep the [timestamp] provided by +the kernel at the begin of in each message rather than to remove it, +when it could be parsed and converted into local time for use as +regular message time. Only used, when $klogParseKernelTimestamp is +on. + + +LogPath +^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "(see description)", "no", "``$klogpath``" + +Defines the path to the log file that is used. +If this parameter is not set a default will be used. +On Linux "/proc/kmsg" and else "/dev/klog". + + +RatelimitInterval +^^^^^^^^^^^^^^^^^ +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "none" + +.. versionadded:: 8.35.0 + +The rate-limiting interval in seconds. Value 0 turns off rate limiting. +Set it to a number of seconds (5 recommended) to activate rate-limiting. + + +RatelimitBurst +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "10000", "no", "none" + +.. versionadded:: 8.35.0 + +Specifies the rate-limiting burst in number of messages. Set it high to +preserve all bootup messages. + + +Caveats/Known Bugs +================== + +This is obviously platform specific and requires platform drivers. +Currently, imklog functionality is available on Linux and BSD. + +This module is **not supported on Solaris** and not needed there. For +Solaris kernel input, use :doc:`imsolaris <imsolaris>`. + + +Example 1 +========= + +The following sample pulls messages from the kernel log. All parameters +are left by default, which is usually a good idea. Please note that +loading the plugin is sufficient to activate it. No directive is needed +to start pulling kernel messages. + +.. code-block:: none + + module(load="imklog") + + +Example 2 +========= + +The following sample adds a ratelimiter. The burst and interval are +set high to allow for a large volume of messages on boot. + +.. code-block:: none + + module(load="imklog" RatelimitBurst="5000" RatelimitInterval="5") + + +Unsupported |FmtObsoleteName| directives +======================================== + +.. function:: $DebugPrintKernelSymbols on/off + + Linux only, ignored on other platforms (but may be specified). + Defaults to off. + +.. function:: $klogLocalIPIF + + This directive is no longer supported. Instead, use the global + $localHostIPIF directive instead. + + +.. function:: $klogUseSyscallInterface on/off + + Linux only, ignored on other platforms (but may be specified). + Defaults to off. + +.. function:: $klogSymbolsTwice on/off + + Linux only, ignored on other platforms (but may be specified). + Defaults to off. + + diff --git a/source/configuration/modules/imkmsg.rst b/source/configuration/modules/imkmsg.rst new file mode 100644 index 0000000..318c9f5 --- /dev/null +++ b/source/configuration/modules/imkmsg.rst @@ -0,0 +1,188 @@ +********************************** +imkmsg: /dev/kmsg Log Input Module +********************************** + +=========================== =========================================================================== +**Module Name:** **imkmsg** +**Author:** `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com> + Milan Bartos <mbartos@redhat.com> +=========================== =========================================================================== + + +Purpose +======= + +Reads messages from the /dev/kmsg structured kernel log and submits them +to the syslog engine. + +The printk log buffer contains log records. These records are exported +by /dev/kmsg device as structured data in the following format: +"level,sequnum,timestamp;<message text>\\n" +There could be continuation lines starting with space that contains +key/value pairs. +Log messages are parsed as necessary into rsyslog msg\_t structure. +Continuation lines are parsed as json key/value pairs and added into +rsyslog's message json representation. + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + +Module Parameters +----------------- + +Mode +^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "parseKernelTimestamp", "no", "none" + +.. versionadded:: 8.2312.0 + +This parameter configures which timestamps will be used. It is an advanced +setting and most users should probably keep the default mode ("startup"). + +The linux kernel message buffer contains a timestamp, which reflects the time +the message was created. However, this is not the "normal" time one expects, but +in a so-called monotonic time in seconds since kernel start. For a datacenter +system which runs 24 hours by 7 days a week, kernel time and actual +wall clock time is mostly the same. Problems may occur during daylight +savings time switches. + +For desktops and laptops this is not necessarily the case. The reason is, as +it looks, that during low power states (energy save mode, hibernation), kernel +monotonic time **does not advance**. This is also **not** corrected when the +system comes back to normal operations. As such, on systems using low power +states from time to time, kernel time and wallclock time drift apart. We have +been told cases where this is in the magnitude of days. Just think about +desktops which are in hibernate during the night, missing several hours +each day. So this is a real-world problem. + +To work around this, we usually do **not** use the kernel timstamp when +we calculate the message time. Instead, we use wallclock time (obtained +from the respective linux timer) of the instant when imkmsg reads the +message from the kernel log. As message creation and imkmsg reading it +is usually in very close time proximity, this approach works very well. + +**However**, this is not helpful for e.g. early boot messages. These +were potentially generated some seconds to a minute or two before rsyslog +startup. To provide a proper meaning of time for these events, we use +the kernel timstamp instead of wallclock time during rsyslog startup. +This is most probably correct, because it is extremely unlikely (close +to impossible) that the system entered a low-power state before rsyslog +startup. + +**Note well:** When rsyslog is restarted during normal system operations, +existing imkmsg messages are re-read and this is done with the kernel +timestamp. This causes message duplication, but is what imkmsg always +did. It is planned to provide ehance the module to improve this +behaviour. This documentation page here will be updated when changes are +made. + +The *parseKernelTimestamp* parameter provides fine-grain control over +the processing of kernel vs. wallclock time. Adjustments should only +be needed rarely and if there is a dedicated use case for it. So use +this parameter only if you have a good reason to do so. + +Supported modes are: + +* **startup** - This is the **DEFAULT setting**. + + Uses the kernel time stamp during the initial read + loop of /dev/kmsg, but uses system wallclock time once the initial + read is completed. This behavior is described in the text above in + detail. + +* **on** - kernel timestamps are always used and wallclock time never + +* **off** - kernel timestamps are never used, system wallclock time is + always used + + +readMode +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "full-boot", "no", "none" + +.. versionadded:: 8.2312.0 + +This parameter permits to control when imkmsg reads the full kernel. + +It provides the following options: + +* **full-boot** - (default) read full klog, but only "immediately" after + boot. "Immediately" is hereby meant in seconds of system uptime + given in "expectedBootCompleteSeconds" + +* **full-always** - read full klog on every rsyslog startup. Most probably + causes message duplication + +* **new-only** - never emit existing kernel log message, read only new ones. + +Note that some message loss can happen if rsyslog is stopped in "full-boot" and +"new-only" read mode. The longer rsyslog is inactive, the higher the message +loss probability and potential number of messages lost. For typical restart +scenarios, this should be minimal. On HUP, no message loss occurs as rsyslog +is not actually stopped. + + +expectedBootCompleteSeconds +^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "positive integer", "90", "no", "none" + +.. versionadded:: 8.2312.0 + +This parameter works in conjunction with **readMode** and specifies how +many seconds after startup the system should be considered to be +"just booted", which means in **readMode** "full-boot" imkmsg reads and +forwards to rsyslog processing all existing messages. + +In any other **readMode** the **expectedBootCompleteSettings** is +ignored. + +Caveats/Known Bugs: +=================== + +This module cannot be used together with imklog module. When using one of +them, make sure the other one is not enabled. + +This is Linux specific module and requires /dev/kmsg device with +structured kernel logs. + +This module does not support rulesets. All messages are delivered to the +default rulseset. + + + +Examples +======== + +The following sample pulls messages from the /dev/kmsg log device. All +parameters are left by default, which is usually a good idea. Please +note that loading the plugin is sufficient to activate it. No directive +is needed to start pulling messages. + +.. code-block:: none + + module(load="imkmsg") + + diff --git a/source/configuration/modules/immark.rst b/source/configuration/modules/immark.rst new file mode 100644 index 0000000..cbae437 --- /dev/null +++ b/source/configuration/modules/immark.rst @@ -0,0 +1,41 @@ +********************************** +immark: Mark Message Input Module +********************************** + +=========================== =========================================================================== +**Module Name:** **immark** +**Author:** `Rainer Gerhards <http://www.gerhards.net/rainer>`_ <rgerhards@adiscon.com> +=========================== =========================================================================== + +Purpose +======= + +This module provides the ability to inject periodic "mark" messages to +the input of rsyslog. This is useful to allow for verification that +the logging system is functioning. + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + +Module Parameters +----------------- + +interval +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "max", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "1200", "", "no", "``$MarkMessagePeriod``" + +Specifies the mark message injection interval in seconds. + +.. seealso:: + + The Action Parameter ``action.writeAllMarkMessages`` in :doc:`../actions`. diff --git a/source/configuration/modules/impcap.rst b/source/configuration/modules/impcap.rst new file mode 100644 index 0000000..99e0f49 --- /dev/null +++ b/source/configuration/modules/impcap.rst @@ -0,0 +1,255 @@ + +******************************* +Impcap: network traffic capture +******************************* + +==================== ===================================== +**Module Name:** **impcap** +**Author:** Theo Bertin <theo.bertin@advens.fr> +==================== ===================================== + +Purpose +======= + +Impcap is an input module based upon `tcpdump's libpcap <https://www.tcpdump.org/>`_ library for network traffic capture. + +Its goal is to capture network traffic with efficiency, parse network packets metadata AND data, and allow users/modules +to make full use of it. + + + +Configuration Parameters +======================== + +.. note:: + Parameter names are case-insensitive + +Module Parameter +---------------- + +metadata_container +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "!impcap", "no", "none" + +Defines the container to place all the parsed metadata of the network packet. + +.. Warning:: + if overwritten, this parameter should always begin with '!' to define the JSON object accompanying messages. No checks are done to ensure that + and not complying with this rule will prevent impcap/rsyslog from running, or will result in unexpected behaviours. + + +data_container +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "!data", "no", "none" + +Defines the container to place all the data of the network packet. 'data' here defines everything above transport layer +in the OSI model, and is a string representation of the hexadecimal values of the stream. + +.. Warning:: + if overwritten, this parameter should always begin with '!' to define the JSON object accompanying messages. No checks are done to ensure that + and not complying with this rule will prevent impcap/rsyslog from running, or will result in unexpected behaviours. + + + +snap_length +^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "number", "65535", "no", "none" + +Defines the maximum size of captured packets. +If captured packets are longer than the defined value, they will be capped. +Default value allows any type of packet to be captured entirely but can be much shorter if only metadata capture is +desired (500 to 2000 should still be safe, depending on network protocols). +Be wary though, as impcap won't be able to parse metadata correctly if the value is not high enough. + + +Input Parameters +---------------- + +interface +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +This parameter specifies the network interface to listen to. **If 'interface' is not specified, 'file' must be in order +for the module to run.** + +.. note:: + The name must be a valid network interface on the system (such as 'lo'). + see :ref:`Supported interface types` for an exhaustive list of all supported interface link-layer types. + + +file +^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +This parameter specifies a pcap file to read. +The file must respect the `pcap file format specification <https://www.tcpdump.org/pcap/pcap.html>`_. **If 'file' is not specified, 'interface' must be in order +for the module to run.** + +.. Warning:: + This functionality is not intended for production environnments, + it is designed for development/tests. + + +promiscuous +^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "boolean", "off", "no", "none" + +When a valid interface is provided, sets the capture to promiscuous for this interface. + +.. warning:: + Setting your network interface to promiscuous can come against your local laws and + regulations, maintainers cannot be held responsible for improper use of the module. + + +filter +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +Set a filter for the capture. +Filter semantics are defined `on pcap manpages <https://www.tcpdump.org/manpages/pcap-filter.7.html>`_. + + +tag +^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +Set a tag to messages coming from this input. + + +ruleset +^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +Assign messages from thi simput to a specific Rsyslog ruleset. + + +.. _no_buffer: + +no_buffer +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "boolean", "off", "no", "none" + +Disable buffering during capture. +By default, impcap asks the system to bufferize packets (see parameters :ref:`buffer_size`, :ref:`buffer_timeout` and +:ref:`packet_count`), this parameter disables buffering completely. This means packets will be handled as soon as they +arrive, but impcap will make more system calls to get them and might miss some depending on the incoming rate and system +performances. + + +.. _buffer_size: + +buffer_size +^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "number (octets)", "15740640", "no", "none" + +Set a buffer size in bytes to the capture handle. +This parameter is only relevant when :ref:`no_buffer` is not active, and should be set depending on input packet rates, +:ref:`buffer_timeout` and :ref:`packet_count` values. + + +.. _buffer_timeout: + +buffer_timeout +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "number (ms)", "10", "no", "none" + +Set a timeout in milliseconds between two system calls to get bufferized packets. This parameter prevents low input rate +interfaces to keep packets in buffers for too long, but does not guarantee fetch every X seconds (see `pcap manpage <https://www.tcpdump.org/manpages/pcap.3pcap.html>`_ for more details). + + + +.. _packet_count: + +packet_count +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "number", "5", "no", "none" + +Set a maximum number of packets to process at a time. This parameter allows to limit batch calls to a maximum of X +packets at a time. + + +.. _Supported interface types: + +Supported interface types +========================= + +Impcap currently supports IEEE 802.3 Ethernet link-layer type interfaces. +Please contact the maintainer if you need a different interface type ! diff --git a/source/configuration/modules/improg.rst b/source/configuration/modules/improg.rst new file mode 100644 index 0000000..a0fd746 --- /dev/null +++ b/source/configuration/modules/improg.rst @@ -0,0 +1,170 @@ +**************************************** +improg: Program integration input module +**************************************** + +================ ============================================================== +**Module Name:** **improg** +**Authors:** Jean-Philippe Hilaire <jean-philippe.hilaire@pmu.fr> & Philippe Duveau <philippe.duveau@free.fr> +================ ============================================================== + + +Purpose +======= + +This module allows rsyslog to spawn external command(s) and consume message +from pipe(s) (stdout of the external process). + +**Limitation:** `select()` seems not to support usage of `printf(...)` or +`fprintf(stdout,...)`. Only `write(STDOUT_FILENO,...)` seems to be efficient. + +The imput module consume pipes form all external programs in a mono-threaded +`runInput` method. This means that data treatments will be serialized. + +Optionally, the module manage the external program through keyword sent to +it using a second pipe to stdin of the external process. + +An operational sample in C can be found @ "github.com/pduveau/jsonperfmon" + +Also a bash's script is provided as tests/improg-simul.sh. The `echo` and `read` (built-in) can be used to communicate with the module. +External commands can not be used to communicate. `printf` is unable to send data directly to the module but can used through a variable and `echo`. + + +Compile +======= + +To successfully compile improg module. + + ./configure --enable-improg ... + +Configuration Parameters +======================== + +Action Parameters +----------------- + +Binary +^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "yes", "command arguments...", + +Command line : external program and arguments + +Tag +^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "yes", ,"none" + +The tag to be assigned to messages read from this file. If you would like to +see the colon after the tag, you need to include it when you assign a tag +value, like so: ``tag="myTagValue:"``. + +Facility +^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "no", "facility\|number", "local0" + +The syslog facility to be assigned to messages read from this file. Can be +specified in textual form (e.g. ``local0``, ``local1``, ...) or as numbers (e.g. +16 for ``local0``). Textual form is suggested. + +Severity +^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "no", "severity\|number", "notice" + +The syslog severity to be assigned to lines read. Can be specified +in textual form (e.g. ``info``, ``warning``, ...) or as numbers (e.g. 6 +for ``info``). Textual form is suggested. + +confirmMessages +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "binary", "no", "on\|off", "on" + +Specifies whether the external program needs feedback from rsyslog via stdin. +When this switch is set to "on", rsyslog confirms each received message. +This feature facilitates error handling: instead of having to implement a retry +logic, the external program can rely on the rsyslog queueing capabilities. +The program receives a line with the word ``ACK`` from its standard input. + +Also, the program receives a ``STOP`` when rsyslog ask the module to stop. + +signalOnClose +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "binary", "no", "on\|off", "off" + +Specifies whether a TERM signal must be sent to the external program before +closing it (when either the worker thread has been unscheduled, a restart +of the program is being forced, or rsyslog is about to shutdown). + +closeTimeout +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "number", "no", ,"200" + +Specifies whether a KILL signal must be sent to the external program in case +it does not terminate within the timeout indicated by closeTimeout_ +(when either the worker thread has been unscheduled, a restart of the program +is being forced, or rsyslog is about to shutdown). + +killUnresponsive +^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "binary", "no", "on\|off", "on" + +Specifies whether a KILL signal must be sent to the external program in case +it does not terminate within the timeout indicated by closeTimeout +(when either the worker thread has been unscheduled, a restart of the program +is being forced, or rsyslog is about to shutdown). + +Stop sequence +============= + +1. If `confirmMessages` is set to on, a `STOP` is written in stdin of the child. +2. If `signalOnClose` is set to "on", a TERM signal is sent to the child. +3. The pipes with the child process are closed (the child will receive EOF on stdin), +4. Then, rsyslog waits for the child process to terminate during closeTimeout, +5. If the child has not terminated within the timeout, a KILL signal is sent to it. + + diff --git a/source/configuration/modules/impstats.rst b/source/configuration/modules/impstats.rst new file mode 100644 index 0000000..ca95609 --- /dev/null +++ b/source/configuration/modules/impstats.rst @@ -0,0 +1,405 @@ +*********************************************************** +impstats: Generate Periodic Statistics of Internal Counters +*********************************************************** + +=========================== =========================================================================== +**Module Name:** **impstats** +**Author:** `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com> +=========================== =========================================================================== + + +Purpose +======= + +This module provides periodic output of rsyslog internal counters. + +The set of available counters will be output as a set of syslog +messages. This output is periodic, with the interval being configurable +(default is 5 minutes). Be sure that your configuration records the +counter messages (default is syslog.=info). Besides logging to the +regular syslog stream, the module can also be configured to write +statistics data into a (local) file. + +When logging to the regular syslog stream, impstats records are emitted +just like regular log messages. As such, +counters increase when processing these messages. This must be taken into +consideration when testing and troubleshooting. + +Note that loading this module has some impact on rsyslog performance. +Depending on settings, this impact may be noticeable for high-load +environments, but in general the overhead is pretty light. + +**Note that there is a** `rsyslog statistics online +analyzer <http://www.rsyslog.com/impstats-analyzer/>`_ **available.** It +can be given a impstats-generated file and will return problems it +detects. Note that the analyzer cannot replace a human in getting things +right, but it is expected to be a good aid in starting to understand and +gain information from the pstats logs. + +The rsyslog website has an overview of available `rsyslog +statistic counters <http://rsyslog.com/rsyslog-statistic-counter/>`_. +When browsing this page, please be sure to take note of which rsyslog +version is required to provide a specific counter. Counters are +continuously being added, and older versions do not support everything. + + +Notable Features +================ + +- :ref:`impstats-statistic-counter` + + + + +Configuration Parameters +======================== + +The configuration parameters for this module are designed for tailoring +the method and process for outputting the rsyslog statistics to file. + +.. note:: + + Parameter names are case-insensitive. + +.. note:: + + This module supports module parameters, only. + + +Module Parameters +----------------- + +Interval +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "300", "no", "none" + +Sets the interval, in **seconds** at which messages are generated. +Please note that the actual interval may be a bit longer. We do not +try to be precise and so the interval is actually a sleep period +which is entered after generating all messages. So the actual +interval is what is configured here plus the actual time required to +generate messages. In general, the difference should not really +matter. + + +Facility +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "5", "no", "none" + +The numerical syslog facility code to be used for generated +messages. Default is 5 (syslog). This is useful for filtering +messages. + + +Severity +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "6", "no", "none" + +The numerical syslog severity code to be used for generated +messages. Default is 6 (info).This is useful for filtering messages. + + +ResetCounters +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +When set to "on", counters are automatically reset after they are +emitted. In that case, the contain only deltas to the last value +emitted. When set to "off", counters always accumulate their values. +Note that in auto-reset mode not all counters can be reset. Some +counters (like queue size) are directly obtained from internal object +and cannot be modified. Also, auto-resetting introduces some +additional slight inaccuracies due to the multi-threaded nature of +rsyslog and the fact that for performance reasons it cannot serialize +access to counter variables. As an alternative to auto-reset mode, +you can use rsyslog's statistics manipulation scripts to create delta +values from the regular statistic logs. This is the suggested method +if deltas are not necessarily needed in real-time. + + +Format +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "legacy", "no", "none" + +.. versionadded:: 8.16.0 + +Specifies the format of emitted stats messages. The default of +"legacy" is compatible with pre v6-rsyslog. The other options provide +support for structured formats (note the "cee" is actually "project +lumberjack" logging). + +The json-elasticsearch format supports the broken ElasticSearch +JSON implementation. ES 2.0 no longer supports valid JSON and +disallows dots inside names. The "json-elasticsearch" format +option replaces those dots by the bang ("!") character. So +"discarded.full" becomes "discarded!full". +Options: json/json-elasticsearch/cee/legacy + + +log.syslog +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "none" + +This is a boolean setting specifying if data should be sent to the +usual syslog stream. This is useful if custom formatting or more +elaborate processing is desired. However, output is placed under the +same restrictions as regular syslog data, especially in regard to the +queue position (stats data may sit for an extended period of time in +queues if they are full). If set "off", then you cannot bind the module to +ruleset. + + +log.file +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +If specified, statistics data is written to the specified file. For +robustness, this should be a local file. The file format cannot be +customized, it consists of a date header, followed by a colon, +followed by the actual statistics record, all on one line. Only very +limited error handling is done, so if things go wrong stats records +will probably be lost. Logging to file an be a useful alternative if +for some reasons (e.g. full queues) the regular syslog stream method +shall not be used solely. Note that turning on file logging does NOT +turn off syslog logging. If that is desired log.syslog="off" must be +explicitly set. + + +Ruleset +^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +Binds the listener to a specific :doc:`ruleset <../../concepts/multi_ruleset>`. + +**Note** that setting ``ruleset`` and ``log.syslog="off"`` are mutually +exclusive because syslog stream processing must be enabled to use a ruleset. + + +Bracketing +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +.. versionadded:: 8.4.1 + +This is a utility setting for folks who post-process impstats logs +and would like to know the begin and end of a block of statistics. +When "bracketing" is set to "on", impstats issues a "BEGIN" message +before the first counter is issued, then all counter values +are issued, and then an "END" message follows. As such, if and only if messages +are kept in sequence, a block of stats counts can easily be identified +by those BEGIN and END messages. + +**Note well:** in general, sequence of syslog messages is **not** +strict and is not ordered in sequence of message generation. There +are various occasion that can cause message reordering, some +examples are: + +* using multiple threads +* using UDP forwarding +* using relay systems, especially with buffering enabled +* using disk-assisted queues + +This is not a problem with rsyslog, but rather the way a concurrent +world works. For strict order, a specific order predicate (e.g. a +sufficiently fine-grained timestamp) must be used. + +As such, BEGIN and END records may actually indicate the begin and +end of a block of statistics - or they may *not*. Any order is possible +in theory. So the bracketing option does not in all cases work as +expected. This is the reason why it is turned off by default. + +*However*, bracketing may still be useful for many use cases. First +and foremost, while there are many scenarios in which messages become +reordered, in practice it happens relatively seldom. So most of the +time the statistics records will come in as expected and actually +will be bracketed by the BEGIN and END messages. Consequently, if +an application can handle occasional out-of-order delivery (e.g. by +graceful degradation), bracketing may actually be a great solution. +It is, however, very important to know and +handle out of order delivery. For most real-world deployments, +a good way to handle it is to ignore unexpected +records and use the previous values for ones missing in the current +block. To guard against two or more blocks being mixed, it may also +be a good idea to never reset a value to a lower bound, except when +that lower bound is seen consistently (which happens due to a +restart). Note that such lower bound logic requires *resetCounters* +to be set to off. + + +.. _impstats-statistic-counter: + +Statistic Counter +================= + +The impstats plugin gathers some internal :doc:`statistics <../rsyslog_statistic_counter>`. +They have different names depending on the actual statistics. Obviously, they do not +relate to the plugin itself but rather to a broader object – most notably the +rsyslog process itself. The "resource-usage" counter maintains process +statistics. They base on the getrusage() system call. The counters are +named like getrusage returned data members. So for details, looking them +up in "man getrusage" is highly recommended, especially as value may be +different depending on the platform. A getrusage() call is done immediately +before the counter is emitted. The following individual counters are +maintained: + +- ``utime`` - this is the user time in microseconds (thus the timeval structure combined) +- ``stime`` - again, time given in microseconds +- ``maxrss`` +- ``minflt`` +- ``majflt`` +- ``inblock`` +- ``outblock`` +- ``nvcsw`` +- ``nivcsw`` +- ``openfiles`` - number of file handles used by rsyslog; includes actual files, sockets and others + + +Caveats/Known Bugs +================== + +- This module MUST be loaded right at the top of rsyslog.conf, + otherwise stats may not get turned on in all places. + + +Examples +======== + +Load module, send stats data to syslog stream +--------------------------------------------- + +This activates the module and records messages to /var/log/rsyslog-stats +in 10 minute intervals: + +.. code-block:: none + + module(load="impstats" + interval="600" + severity="7") + + # to actually gather the data: + syslog.=debug /var/log/rsyslog-stats + + +Load module, send stats data to local file +------------------------------------------ + +Here, the default interval of 5 minutes is used. However, this time, stats +data is NOT emitted to the syslog stream but to a local file instead. + +.. code-block:: none + + module(load="impstats" + interval="600" + severity="7" + log.syslog="off" + # need to turn log stream logging off! + log.file="/path/to/local/stats.log") + + +Load module, send stats data to local file and syslog stream +------------------------------------------------------------ + +Here we log to both the regular syslog log stream as well as a +file. Within the log stream, we forward the data records to another +server: + +.. code-block:: none + + module(load="impstats" + interval="600" + severity="7" + log.file="/path/to/local/stats.log") + + syslog.=debug @central.example.net + + +Explanation of output +===================== + +Example output for illustration:: + + Sep 17 11:43:49 localhost rsyslogd-pstats: imuxsock: submitted=16 + Sep 17 11:43:49 localhost rsyslogd-pstats: main Q: size=1 enqueued=2403 full=0 maxqsize=2 + +Explanation: + +All objects are shown in the results with a separate counter, one object per +line. + +Line 1: shows details for + +- ``imuxsock``, an object +- ``submitted=16``, a counter showing that 16 messages were received by the + imuxsock object. + +Line 2: shows details for the main queue: + +- ``main Q``, an object +- ``size``, messages in the queue +- ``enqueued``, all received messages thus far +- ``full``, how often was the queue was full +- ``maxqsize``, the maximum amount of messages that have passed through the + queue since rsyslog was started + +See Also +======== + +- `rsyslog statistics + counter <http://www.rsyslog.com/rsyslog-statistic-counter/>`_ +- `impstats delayed or + lost <http://www.rsyslog.com/impstats-delayed-or-lost/>`_ - cause and + cure diff --git a/source/configuration/modules/imptcp.rst b/source/configuration/modules/imptcp.rst new file mode 100644 index 0000000..e495155 --- /dev/null +++ b/source/configuration/modules/imptcp.rst @@ -0,0 +1,711 @@ +************************ +imptcp: Plain TCP Syslog +************************ + +=========================== =========================================================================== +**Module Name:** **imptcp** +**Author:** `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com> +=========================== =========================================================================== + + +Purpose +======= + +Provides the ability to receive syslog messages via plain TCP syslog. +This is a specialised input plugin tailored for high performance on +Linux. It will probably not run on any other platform. Also, it does not +provide TLS services. Encryption can be provided by using +`stunnel <rsyslog_stunnel.html>`_. + +This module has no limit on the number of listeners and sessions that +can be used. + + +Notable Features +================ + +- :ref:`imptcp-statistic-counter` +- :ref:`error-messages` + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + + +Module Parameters +----------------- + +Threads +^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "2", "no", "``$InputPTCPServerHelperThreads``" + +Number of helper worker threads to process incoming messages. These +threads are utilized to pull data off the network. On a busy system, +additional helper threads (but not more than there are CPUs/Cores) +can help improving performance. The default value is two, which means +there is a default thread count of three (the main input thread plus +two helpers). No more than 16 threads can be set (if tried to, +rsyslog always resorts to 16). + + +MaxSessions +^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "none" + +Maximum number of open sessions allowed. This is inherited to each +"input()" config, however it is not a global maximum, rather just +setting the default per input. + +A setting of zero or less than zero means no limit. + +ProcessOnPoller +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "none" + +Instructs imptcp to process messages on poller thread opportunistically. +This leads to lower resource footprint(as poller thread doubles up as +message-processing thread too). "On" works best when imptcp is handling +low ingestion rates. + +At high throughput though, it causes polling delay(as poller spends time +processing messages, which keeps connections in read-ready state longer +than they need to be, filling socket-buffer, hence eventually applying +backpressure). + +It defaults to allowing messages to be processed on poller (for backward +compatibility). + + +Input Parameters +---------------- + +These parameters can be used with the "input()" statement. They apply to +the input they are specified with. + + +Port +^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "``$InputPTCPServerRun``" + +Select a port to listen on. It is an error to specify +both `path` and `port`. + + +Path +^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +A path on the filesystem for a unix domain socket. It is an error to specify +both `path` and `port`. + + +DiscardTruncatedMsg +^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +When a message is split because it is to long the second part is normally +processed as the next message. This can cause Problems. When this parameter +is turned on the part of the message after the truncation will be discarded. + +FileOwner +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "UID", "system default", "no", "none" + +Set the file owner for the domain socket. The +parameter is a user name, for which the userid is obtained by +rsyslogd during startup processing. Interim changes to the user +mapping are *not* detected. + + +FileOwnerNum +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "system default", "no", "none" + +Set the file owner for the domain socket. The +parameter is a numerical ID, which which is used regardless of +whether the user actually exists. This can be useful if the user +mapping is not available to rsyslog during startup. + + +FileGroup +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "GID", "system default", "no", "none" + +Set the group for the domain socket. The parameter is +a group name, for which the groupid is obtained by rsyslogd during +startup processing. Interim changes to the user mapping are not +detected. + + +FileGroupNum +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "system default", "no", "none" + +Set the group for the domain socket. The parameter is +a numerical ID, which is used regardless of whether the group +actually exists. This can be useful if the group mapping is not +available to rsyslog during startup. + + +FileCreateMode +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "octalNumber", "0644", "no", "none" + +Set the access permissions for the domain socket. The value given must +always be a 4-digit octal number, with the initial digit being zero. +Please note that the actual permission depend on rsyslogd's process +umask. If in doubt, use "$umask 0000" right at the beginning of the +configuration file to remove any restrictions. + + +FailOnChOwnFailure +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "none" + +Rsyslog will not start if this is on and changing the file owner, group, +or access permissions fails. Disable this to ignore these errors. + + +Unlink +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +If a unix domain socket is being used this controls whether or not the socket +is unlinked before listening and after closing. + + +Name +^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "imptcp", "no", "``$InputPTCPServerInputName``" + +Sets a name for the inputname property. If no name is set "imptcp" +is used by default. Setting a name is not strictly necessary, but can +be useful to apply filtering based on which input the message was +received from. Note that the name also shows up in +:doc:`impstats <impstats>` logs. + + +Ruleset +^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "``$InputPTCPServerBindRuleset``" + +Binds specified ruleset to this input. If not set, the default +ruleset is bound. + + +MaxFrameSize +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "200000", "no", "none" + +When in octet counted mode, the frame size is given at the beginning +of the message. With this parameter the max size this frame can have +is specified and when the frame gets to large the mode is switched to +octet stuffing. +The max value this parameter can have was specified because otherwise +the integer could become negative and this would result in a +Segmentation Fault. (Max Value: 200000000) + + +MaxSessions +^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "none" + +Maximum number of open sessions allowed. If more tcp connections +are created then rsyslog will drop those connections. Warning, +this defaults to 0 which means unlimited, so take care to set this +if you have limited memory and/or processing power. + +A setting of zero or negative integer means no limit. + +Address +^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "``$InputPTCPServerListenIP``" + +On multi-homed machines, specifies to which local address the +listener should be bound. + + +AddtlFrameDelimiter +^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "-1", "no", "``$InputPTCPServerAddtlFrameDelimiter``" + +This directive permits to specify an additional frame delimiter for +plain tcp syslog. The industry-standard specifies using the LF +character as frame delimiter. Some vendors, notable Juniper in their +NetScreen products, use an invalid frame delimiter, in Juniper's case +the NUL character. This directive permits to specify the ASCII value +of the delimiter in question. Please note that this does not +guarantee that all wrong implementations can be cured with this +directive. It is not even a sure fix with all versions of NetScreen, +as I suggest the NUL character is the effect of a (common) coding +error and thus will probably go away at some time in the future. But +for the time being, the value 0 can probably be used to make rsyslog +handle NetScreen's invalid syslog/tcp framing. For additional +information, see this `forum +thread <http://kb.monitorware.com/problem-with-netscreen-log-t1652.html>`_. +**If this doesn't work for you, please do not blame the rsyslog team. +Instead file a bug report with Juniper!** + +Note that a similar, but worse, issue exists with Cisco's IOS +implementation. They do not use any framing at all. This is confirmed +from Cisco's side, but there seems to be very limited interest in +fixing this issue. This directive **can not** fix the Cisco bug. That +would require much more code changes, which I was unable to do so +far. Full details can be found at the `Cisco tcp syslog +anomaly <http://www.rsyslog.com/Article321.phtml>`_ page. + + +SupportOctetCountedFraming +^^^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "``$InputPTCPServerSupportOctetCountedFraming``" + +The legacy octed-counted framing (similar to RFC5425 +framing) is activated. This is the default and should be left +unchanged until you know very well what you do. It may be useful to +turn it off, if you know this framing is not used and some senders +emit multi-line messages into the message stream. + + +NotifyOnConnectionClose +^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "``$InputPTCPServerNotifyOnConnectionClose``" + +Instructs imptcp to emit a message if a remote peer closes the +connection. + + +NotifyOnConnectionOpen +^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +Instructs imptcp to emit a message if a remote peer opens a +connection. Hostname of the remote peer is given in the message. + + +KeepAlive +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "``$InputPTCPServerKeepAlive``" + +Enable of disable keep-alive packets at the tcp socket layer. The +default is to disable them. + + +KeepAlive.Probes +^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "``$InputPTCPServerKeepAlive_probes``" + +The number of unacknowledged probes to send before considering the +connection dead and notifying the application layer. The default, 0, +means that the operating system defaults are used. This has only +effect if keep-alive is enabled. The functionality may not be +available on all platforms. + + +KeepAlive.Interval +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "``$InputPTCPServerKeepAlive_intvl``" + +The interval between subsequential keepalive probes, regardless of +what the connection has exchanged in the meantime. The default, 0, +means that the operating system defaults are used. This has only +effect if keep-alive is enabled. The functionality may not be +available on all platforms. + + +KeepAlive.Time +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "``$InputPTCPServerKeepAlive_time``" + +The interval between the last data packet sent (simple ACKs are not +considered data) and the first keepalive probe; after the connection +is marked to need keepalive, this counter is not used any further. +The default, 0, means that the operating system defaults are used. +This has only effect if keep-alive is enabled. The functionality may +not be available on all platforms. + + +RateLimit.Interval +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "none" + +Specifies the rate-limiting interval in seconds. Set it to a number +of seconds (5 recommended) to activate rate-limiting. + + +RateLimit.Burst +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "10000", "no", "none" + +Specifies the rate-limiting burst in number of messages. + + +Compression.mode +^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +This is the counterpart to the compression modes set in +:doc:`omfwd <omfwd>`. +Please see it's documentation for details. + + +flowControl +^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "none" + +Flow control is used to throttle the sender if the receiver queue is +near-full preserving some space for input that can not be throttled. + + +MultiLine +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +Experimental parameter which causes rsyslog to recognise a new message +only if the line feed is followed by a '<' or if there are no more characters. + + +framing.delimiter.regex +^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "off", "no", "none" + +Experimental parameter. It is similar to "MultiLine", but provides greater +control of when a log message ends. You can specify a regular expression that +characterizes the header to expect at the start of the next message. As such, +it indicates the end of the current message. For example, one can use this +setting to use a RFC3164 header as frame delimiter:: + + framing.delimiter.regex="^<[0-9]{1,3}>(Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec)" + +Note that when oversize messages arrive this mode may have problems finding +the proper frame terminator. There are some provisions inside imptcp to make +these kinds of problems unlikely, but if the messages are very much over the +configured MaxMessageSize, imptcp emits an error messages. Chances are great +it will properly recover from such a situation. + + +SocketBacklog +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "5", "no", "none" + +Specifies the backlog parameter sent to the listen() function. +It defines the maximum length to which the queue of pending connections may grow. +See man page of listen(2) for more information. +The parameter controls both TCP and UNIX sockets backlog parameter. +Default value is arbitrary set to 5. + + +Defaulttz +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +Set default time zone. At most seven chars are set, as we would otherwise +overrun our buffer. + + +Framingfix.cisco.asa +^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +Cisco very occasionally sends a space after a line feed, which thrashes framing +if not taken special care of. When this parameter is set to "on", we permit +space *in front of the next frame* and ignore it. + + +ListenPortFileName +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +.. versionadded:: 8.38.0 + +With this parameter you can specify the name for a file. In this file the +port, imptcp is connected to, will be written. +This parameter was introduced because the testbench works with dynamic ports. + + +.. _imptcp-statistic-counter: + +Statistic Counter +================= + +This plugin maintains :doc:`statistics <../rsyslog_statistic_counter>` for each listener. The statistic is +named "imtcp" , followed by the bound address, listener port and IP +version in parenthesis. For example, the counter for a listener on port +514, bound to all interfaces and listening on IPv6 is called +"imptcp(\*/514/IPv6)". + +The following properties are maintained for each listener: + +- **submitted** - total number of messages submitted for processing since startup + + +.. _error-messages: + +Error Messages +============== + +When a message is to long it will be truncated and an error will show the remaining length of the message and the beginning of it. It will be easier to comprehend the truncation. + + +Caveats/Known Bugs +================== + +- module always binds to all interfaces + + +Examples +======== + +Example 1 +--------- + +This sets up a TCP server on port 514: + +.. code-block:: none + + module(load="imptcp") # needs to be done just once + input(type="imptcp" port="514") + + +Example 2 +--------- + +This creates a listener that listens on the local loopback +interface, only. + +.. code-block:: none + + module(load="imptcp") # needs to be done just once + input(type="imptcp" port="514" address="127.0.0.1") + + +Example 3 +--------- + +Create a unix domain socket: + +.. code-block:: none + + module(load="imptcp") # needs to be done just once + input(type="imptcp" path="/tmp/unix.sock" unlink="on") + + diff --git a/source/configuration/modules/imrelp.rst b/source/configuration/modules/imrelp.rst new file mode 100644 index 0000000..eb0d9c5 --- /dev/null +++ b/source/configuration/modules/imrelp.rst @@ -0,0 +1,595 @@ +************************* +imrelp: RELP Input Module +************************* + +=========================== =========================================================================== +**Module Name:** **imrelp** +**Author:** `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com> +=========================== =========================================================================== + + +Purpose +======= + +Provides the ability to receive syslog messages via the reliable RELP +protocol. This module requires `librelp <http://www.librelp.com>`__ to +be present on the system. From the user's point of view, imrelp works +much like imtcp or imgssapi, except that no message loss can occur. +Please note that with the currently supported RELP protocol version, a +minor message duplication may occur if a network connection between the +relp client and relp server breaks after the client could successfully +send some messages but the server could not acknowledge them. The window +of opportunity is very slim, but in theory this is possible. Future +versions of RELP will prevent this. Please also note that rsyslogd may +lose a few messages if rsyslog is shutdown while a network connection to +the server is broken and could not yet be recovered. Future versions of +RELP support in rsyslog will prevent that issue. Please note that both +scenarios also exist with plain TCP syslog. RELP, even with the small +nits outlined above, is a much more reliable solution than plain TCP +syslog and so it is highly suggested to use RELP instead of plain TCP. +Clients send messages to the RELP server via omrelp. + + +Notable Features +================ + +- :ref:`imrelp-statistic-counter` + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + + +Module Parameters +----------------- + +Ruleset +^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "``$InputRELPServerBindRuleset``" + +.. versionadded:: 7.5.0 + +Binds the specified ruleset to **all** RELP listeners. This can be +overridden at the instance level. + +tls.tlslib +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +.. versionadded:: 8.1903.0 + +Permits to specify the TLS library used by librelp. +All RELP protocol operations are actually performed by librelp and +not rsyslog itself. The value specified is directly passed down to +librelp. Depending on librelp version and build parameters, supported +TLS libraries differ (or TLS may not be supported at all). In this case +rsyslog emits an error message. + +Usually, the following options should be available: "openssl", "gnutls". + +Note that "gnutls" is the current default for historic reasons. We actually +recommend to use "openssl". It provides better error messages and accepts +a wider range of certificate types. + +If you have problems with the default setting, we recommend to switch to +"openssl". + + +Input Parameters +---------------- + +Port +^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "yes", "``$InputRELPServerRun``" + +Starts a RELP server on selected port + +Address +^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +.. versionadded:: 8.37.0 + +Bind the RELP server to that address. If not specified, the server will be +bound to the wildcard address. + +Name +^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "imrelp", "no", "none" + + +Ruleset +^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +Binds specified ruleset to this listener. This overrides the +module-level Ruleset parameter. + + +MaxDataSize +^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "size_nbr", ":doc:`global(maxMessageSize) <../../rainerscript/global>`", "no", "none" + +Sets the max message size (in bytes) that can be received. Messages that +are too long are handled as specified in parameter oversizeMode. Note that +maxDataSize cannot be smaller than the global parameter maxMessageSize. + + +TLS +^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +If set to "on", the RELP connection will be encrypted by TLS, so +that the data is protected against observers. Please note that both +the client and the server must have set TLS to either "on" or "off". +Other combinations lead to unpredictable results. + +*Attention when using GnuTLS 2.10.x or older* + +Versions older than GnuTLS 2.10.x may cause a crash (Segfault) under +certain circumstances. Most likely when an imrelp inputs and an +omrelp output is configured. The crash may happen when you are +receiving/sending messages at the same time. Upgrade to a newer +version like GnuTLS 2.12.21 to solve the problem. + + +TLS.Compression +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +The controls if the TLS stream should be compressed (zipped). While +this increases CPU use, the network bandwidth should be reduced. Note +that typical text-based log records usually compress rather well. + + +TLS.dhbits +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "none" + +This setting controls how many bits are used for Diffie-Hellman key +generation. If not set, the librelp default is used. For security +reasons, at least 1024 bits should be used. Please note that the +number of bits must be supported by GnuTLS. If an invalid number is +given, rsyslog will report an error when the listener is started. We +do this to be transparent to changes/upgrades in GnuTLS (to check at +config processing time, we would need to hardcode the supported bits +and keep them in sync with GnuTLS - this is even impossible when +custom GnuTLS changes are made...). + + +TLS.PermittedPeer +^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "array", "none", "no", "none" + +PermittedPeer places access restrictions on this listener. Only peers which +have been listed in this parameter may connect. The certificate presented +by the remote peer is used for it's validation. + +The *peer* parameter lists permitted certificate fingerprints. Note +that it is an array parameter, so either a single or multiple +fingerprints can be listed. When a non-permitted peer connects, the +refusal is logged together with it's fingerprint. So if the +administrator knows this was a valid request, he can simply add the +fingerprint by copy and paste from the logfile to rsyslog.conf. + +To specify multiple fingerprints, just enclose them in braces like +this: + +.. code-block:: none + + tls.permittedPeer=["SHA1:...1", "SHA1:....2"] + +To specify just a single peer, you can either specify the string +directly or enclose it in braces. You may also use wildcards to match +a larger number of permitted peers, e.g. ``*.example.com``. + +When using wildcards to match larger number of permitted peers, please +know that the implementation is similar to Syslog RFC5425 which means: +This wildcard matches any left-most DNS label in the server name. +That is, the subject ``*.example.com`` matches the server names ``a.example.com`` +and ``b.example.com``, but does not match ``example.com`` or ``a.b.example.com``. + + +TLS.AuthMode +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +Sets the mode used for mutual authentication. + +Supported values are either "*fingerprint*\ " or "*name"*. + +Fingerprint mode basically is what SSH does. It does not require a +full PKI to be present, instead self-signed certs can be used on all +peers. Even if a CA certificate is given, the validity of the peer +cert is NOT verified against it. Only the certificate fingerprint +counts. + +In "name" mode, certificate validation happens. Here, the matching is +done against the certificate's subjectAltName and, as a fallback, the +subject common name. If the certificate contains multiple names, a +match on any one of these names is considered good and permits the +peer to talk to rsyslog. + + +About Chained Certificates +-------------------------- + +.. versionadded:: 8.2008.0 + +With librelp 1.7.0, you can use chained certificates. +If using "openssl" as tls.tlslib, we recommend at least OpenSSL Version 1.1 +or higher. Chained certificates will also work with OpenSSL Version 1.0.2, but +they will be loaded into the main OpenSSL context object making them available +to all librelp instances (omrelp/imrelp) within the same process. + +If this is not desired, you will require to run rsyslog in multiple instances +with different omrelp configurations and certificates. + + +TLS.CaCert +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +The CA certificate that is being used to verify the client certificates. +Has to be configured if TLS.AuthMode is set to "*fingerprint*\ " or "*name"*. + + +TLS.MyCert +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +The machine certificate that is being used for TLS communication. + + +TLS.MyPrivKey +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +The machine private key for the configured TLS.MyCert. + + +TLS.PriorityString +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +This parameter allows passing the so-called "priority string" to +GnuTLS. This string gives complete control over all crypto +parameters, including compression settings. For this reason, when the +prioritystring is specified, the "tls.compression" parameter has no +effect and is ignored. + +Full information about how to construct a priority string can be +found in the GnuTLS manual. At the time of writing, this +information was contained in `section 6.10 of the GnuTLS +manual <http://gnutls.org/manual/html_node/Priority-Strings.html>`_. + +**Note: this is an expert parameter.** Do not use if you do not +exactly know what you are doing. + +tls.tlscfgcmd +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +.. versionadded:: 8.2001.0 + +The setting can be used if tls.tlslib is set to "openssl" to pass configuration commands to +the openssl libray. +OpenSSL Version 1.0.2 or higher is required for this feature. +A list of possible commands and their valid values can be found in the documentation: +https://www.openssl.org/docs/man1.0.2/man3/SSL_CONF_cmd.html + +The setting can be single or multiline, each configuration command is separated by linefeed (\n). +Command and value are separated by equal sign (=). Here are a few samples: + +Example 1 +--------- + +This will allow all protocols except for SSLv2 and SSLv3: + +.. code-block:: none + + tls.tlscfgcmd="Protocol=ALL,-SSLv2,-SSLv3" + + +Example 2 +--------- + +This will allow all protocols except for SSLv2, SSLv3 and TLSv1. +It will also set the minimum protocol to TLSv1.2 + +.. code-block:: none + + tls.tlscfgcmd="Protocol=ALL,-SSLv2,-SSLv3,-TLSv1 + MinProtocol=TLSv1.2" + + +KeepAlive +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +Enable or disable keep-alive packets at the TCP socket layer. By +defauly keep-alives are disabled. + + +KeepAlive.Probes +^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "none" + +The number of keep-alive probes to send before considering the +connection dead and notifying the application layer. The default, 0, +means that the operating system defaults are used. This only has an +effect if keep-alives are enabled. The functionality may not be +available on all platforms. + + +KeepAlive.Interval +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "none" + +The interval between subsequent keep-alive probes, regardless of what +the connection has been exchanged in the meantime. The default, 0, +means that the operating system defaults are used. This only has an effect +if keep-alive is enabled. The functionality may not be available on all +platforms. + + +KeepAlive.Time +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "none" + +The interval between the last data packet sent (simple ACKs are not +considered data) and the first keepalive probe; after the connection +is marked with keep-alive, this counter is not used any further. +The default, 0, means that the operating system defaults are used. +This only has an effect if keep-alive is enabled. The functionality may +not be available on all platforms. + + +oversizeMode +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "truncate", "no", "none" + +.. versionadded:: 8.35.0 + +This parameter specifies how messages that are too long will be handled. +For this parameter the length of the parameter maxDataSize is used. + +- truncate: Messages will be truncated to the maximum message size. +- abort: This is the behaviour until version 8.35.0. Upon receiving a + message that is too long imrelp will abort. +- accept: Messages will be accepted even if they are too long and an error + message will be output. Using this option does have associated risks. + + +flowControl +^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "light", "no", "none" + +.. versionadded:: 8.1911.0 + + +This parameter permits the fine-tuning of the flowControl parameter. +Possible values are "no", "light", and "full". With "light" being the default +and previously only value. + +Changing the flow control setting may be useful for some rare applications, +this is an advanced setting and should only be changed if you know what you +are doing. Most importantly, **rsyslog block incoming data and become +unresponsive if you change flowcontrol to "full"**. While this may be a +desired effect when intentionally trying to make it most unlikely that +rsyslog needs to lose/discard messages, usually this is not what you want. + +General rule of thumb: **if you do not fully understand what this decription +here talks about, leave the parameter at default value**. + +This part of the +documentation is intentionally brief, as one needs to have deep understanding +of rsyslog to evaluate usage of this parameter. If someone has the insight, +the meaning of this parameter is crystal-clear. If not, that someone will +most likely make the wrong decision when changing this parameter away +from the default value. + + +.. _imrelp-statistic-counter: + +Statistic Counter +================= + +This plugin maintains :doc:`statistics <../rsyslog_statistic_counter>` for each listener. +The statistic by default is named "imrelp" , followed by the listener port in +parenthesis. For example, the counter for a listener on port 514 is called "imprelp(514)". +If the input is given a name, that input name is used instead of "imrelp". This counter is +available starting rsyslog 7.5.1 + +The following properties are maintained for each listener: + +- **submitted** - total number of messages submitted for processing since startup + + +Caveats/Known Bugs +================== + +- see description +- To obtain the remote system's IP address, you need to have at least + librelp 1.0.0 installed. Versions below it return the hostname + instead of the IP address. + + +Examples +======== + +Example 1 +--------- + +This sets up a RELP server on port 2514 with a max message size of 10,000 bytes. + +.. code-block:: none + + module(load="imrelp") # needs to be done just once + input(type="imrelp" port="2514" maxDataSize="10k") + + + +Receive RELP traffic via TLS +---------------------------- + +This receives RELP traffic via TLS using the recommended "openssl" library. +Except for encryption support the scenario is the same as in Example 1. + +Certificate files must exist at configured locations. Note that authmode +"certvalid" is not very strong - you may want to use a different one for +actual deployments. For details, see parameter descriptions. + +.. code-block:: none + + module(load="imrelp" tls.tlslib="openssl") + input(type="imrelp" port="2514" maxDataSize="10k" + tls="on" + tls.cacert="/tls-certs/ca.pem" + tls.mycert="/tls-certs/cert.pem" + tls.myprivkey="/tls-certs/key.pem" + tls.authmode="certvalid" + tls.permittedpeer="rsyslog") + diff --git a/source/configuration/modules/imsolaris.rst b/source/configuration/modules/imsolaris.rst new file mode 100644 index 0000000..f215714 --- /dev/null +++ b/source/configuration/modules/imsolaris.rst @@ -0,0 +1,59 @@ +******************************* +imsolaris: Solaris Input Module +******************************* + +=========================== =========================================================================== +**Module Name:** **imsolaris** +**Author:** `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com> +=========================== =========================================================================== + + +Purpose +======= + +Reads local Solaris log messages including the kernel log. + +This module is specifically tailored for Solaris. Under Solaris, there +is no special kernel input device. Instead, both kernel messages as well +as messages emitted via syslog() are received from a single source. + +This module obeys the Solaris door() mechanism to detect a running +syslogd instance. As such, only one can be active at one time. If it +detects another active instance at startup, the module disables itself, +but rsyslog will continue to run. + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + + +|FmtObsoleteName| Directives +---------------------------- + +| functions:: $IMSolarisLogSocketName <name> + + This is the name of the log socket (stream) to read. If not given, + /dev/log is read. + + +Caveats/Known Bugs +================== + +None currently known. For obvious reasons, works on Solaris, only (and +compilation will most probably fail on any other platform). + + +Examples +======== + +The following sample pulls messages from the default log source + +.. code-block:: none + + $ModLoad imsolaris + + diff --git a/source/configuration/modules/imtcp.rst b/source/configuration/modules/imtcp.rst new file mode 100644 index 0000000..052fa6b --- /dev/null +++ b/source/configuration/modules/imtcp.rst @@ -0,0 +1,1086 @@ +****************************** +imtcp: TCP Syslog Input Module +****************************** + +=========================== =========================================================================== +**Module Name:** **imtcp** +**Author:** `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com> +=========================== =========================================================================== + + +Purpose +======= + +Provides the ability to receive syslog messages via TCP. Encryption is +natively provided by selecting the appropriate network stream driver +and can also be provided by using `stunnel <rsyslog_stunnel.html>`_ (an +alternative is the use the `imgssapi <imgssapi.html>`_ module). + + +Notable Features +================ + +- :ref:`imtcp-statistic-counter` + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + + +Module Parameters +----------------- + +AddtlFrameDelimiter +^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "-1", "no", "``$InputTCPServerAddtlFrameDelimiter``" + +.. versionadded:: 4.3.1 + +This directive permits to specify an additional frame delimiter for +Multiple receivers may be configured by specifying $InputTCPServerRun +multiple times. + + +DisableLFDelimiter +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "``$InputTCPServerDisableLFDelimiter``" + +Industry-standard plain text tcp syslog uses the LF to delimit +syslog frames. However, some users brought up the case that it may be +useful to define a different delimiter and totally disable LF as a +delimiter (the use case named were multi-line messages). This mode is +non-standard and will probably come with a lot of problems. However, +as there is need for it and it is relatively easy to support, we do +so. Be sure to turn this setting to "on" only if you exactly know +what you are doing. You may run into all sorts of troubles, so be +prepared to wrangle with that! + + +MaxFrameSize +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "200000", "no", "none" + +When in octet counted mode, the frame size is given at the beginning +of the message. With this parameter the max size this frame can have +is specified and when the frame gets to large the mode is switched to +octet stuffing. +The max value this parameter can have was specified because otherwise +the integer could become negative and this would result in a +Segmentation Fault. (Max Value = 200000000) + + +NotifyOnConnectionOpen +^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "" + +Instructs imtcp to emit a message if the remote peer closes a +connection. + + +NotifyOnConnectionOpen +^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +Instructs imtcp to emit a message if the remote peer opens a +connection. + + +NotifyOnConnectionClose +^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "``$InputTCPServerNotifyOnConnectionClose``" + +Instructs imtcp to emit a message if the remote peer closes a +connection. + + + +KeepAlive +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "``$InputTCPServerKeepAlive``" + +Enable or disable keep-alive packets at the tcp socket layer. The +default is to disable them. + + +KeepAlive.Probes +^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "``$InputTCPServerKeepAlive_probes``" + +The number of unacknowledged probes to send before considering the +connection dead and notifying the application layer. The default, 0, +means that the operating system defaults are used. This has only +effect if keep-alive is enabled. The functionality may not be +available on all platforms. + + +KeepAlive.Time +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "``$InputTCPServerKeepAlive_time``" + +The interval between the last data packet sent (simple ACKs are not +considered data) and the first keepalive probe; after the connection +is marked to need keepalive, this counter is not used any further. +The default, 0, means that the operating system defaults are used. +This has only effect if keep-alive is enabled. The functionality may +not be available on all platforms. + + +KeepAlive.Interval +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "" + +.. versionadded:: 8.2106.0 + +The interval for keep alive packets. + + + + +FlowControl +^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "``$InputTCPFlowControl``" + +This setting specifies whether some message flow control shall be +exercised on the related TCP input. If set to on, messages are +handled as "light delayable", which means the sender is throttled a +bit when the queue becomes near-full. This is done in order to +preserve some queue space for inputs that can not throttle (like +UDP), but it may have some undesired effect in some configurations. +Still, we consider this as a useful setting and thus it is the +default. To turn the handling off, simply configure that explicitly. + + +MaxListeners +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "20", "no", "``$InputTCPMaxListeners``" + +Sets the maximum number of listeners (server ports) supported. +This must be set before the first $InputTCPServerRun directive. + + +MaxSessions +^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "200", "no", "``$InputTCPMaxSessions``" + +Sets the maximum number of sessions supported. This must be set +before the first $InputTCPServerRun directive. + + +StreamDriver.Name +^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +Selects :doc:`network stream driver <../../concepts/netstrm_drvr>` +for all inputs using this module. + + +StreamDriver.Mode +^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "``$InputTCPServerStreamDriverMode``" + +Sets the driver mode for the currently selected +:doc:`network stream driver <../../concepts/netstrm_drvr>`. +<number> is driver specific. + + +StreamDriver.AuthMode +^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "``$InputTCPServerStreamDriverAuthMode``" + +Sets stream driver authentication mode. Possible values and meaning +depend on the +:doc:`network stream driver <../../concepts/netstrm_drvr>`. +used. + + +StreamDriver.PermitExpiredCerts +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "warn", "no", "none" + +Controls how expired certificates will be handled when stream driver is in TLS mode. +It can have one of the following values: + +- on = Expired certificates are allowed + +- off = Expired certificates are not allowed (Default, changed from warn to off since Version 8.2012.0) + +- warn = Expired certificates are allowed but warning will be logged + + +StreamDriver.CheckExtendedKeyPurpose +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +Whether to check also purpose value in extended fields part of certificate +for compatibility with rsyslog operation. (driver-specific) + + +StreamDriver.PrioritizeSAN +^^^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +Whether to use stricter SAN/CN matching. (driver-specific) + + +StreamDriver.TlsVerifyDepth +^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "TLS library default", "no", "none" + + +Specifies the allowed maximum depth for the certificate chain verification. +Support added in v8.2001.0, supported by GTLS and OpenSSL driver. +If not set, the API default will be used. +For OpenSSL, the default is 100 - see the doc for more: +https://www.openssl.org/docs/man1.1.1/man3/SSL_set_verify_depth.html +For GnuTLS, the default is 5 - see the doc for more: +https://www.gnutls.org/manual/gnutls.html + + +PermittedPeer +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "array", "none", "no", "``$InputTCPServerStreamDriverPermittedPeer``" + +Sets permitted peer IDs. Only these peers are able to connect to +the listener. <id-string> semantics depend on the currently +selected AuthMode and +:doc:`network stream driver <../../concepts/netstrm_drvr>`. +PermittedPeer may not be set in anonymous modes. PermittedPeer may +be set either to a single peer or an array of peers either of type +IP or name, depending on the tls certificate. + +Single peer: +PermittedPeer="127.0.0.1" + +Array of peers: +PermittedPeer=["test1.example.net","10.1.2.3","test2.example.net","..."] + + +DiscardTruncatedMsg +^^^^^^^^^^^^^^^^^^^ + +Normally when a message is truncated in octet stuffing mode the part that +is cut off is processed as the next message. When this parameter is activated, +the part that is cut off after a truncation is discarded and not processed. + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + + +gnutlsPriorityString +^^^^^^^^^^^^^^^^^^^^ + +The "gnutls priority string" parameter in rsyslog offers enhanced +customization for secure communications, allowing detailed configuration +of TLS driver properties. This includes specifying handshake algorithms +and other settings for GnuTLS, as well as implementing OpenSSL +configuration commands. Initially developed for GnuTLS, the "gnutls +priority string" has evolved since version v8.1905.0 to also support +OpenSSL, broadening its application and utility in network security +configurations. This update signifies a key advancement in rsyslog's +capabilities, making the "gnutls priority string" an essential +feature for advanced TLS configuration. + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +.. versionadded:: 8.29.0 + + +**Configuring Driver-Specific Properties** + +This configuration string is used to set properties specific to different drivers. Originally designed for the GnuTLS driver, it has been extended to support OpenSSL configuration commands from version v8.1905.0 onwards. + +**GNUTLS Configuration** + +In GNUTLS, this setting determines the handshake algorithms and options for the TLS session. It's designed to allow user overrides of the library's default settings. If you leave this parameter unset (NULL), the system will revert to the default settings. For more detailed information on priority strings in GNUTLS, you can refer to the GnuTLS Priority Strings Documentation available at [GnuTLS Website](https://gnutls.org/manual/html_node/Priority-Strings.html). + +**OpenSSL Configuration** + +This feature is compatible with OpenSSL Version 1.0.2 and above. It enables the passing of configuration commands to the OpenSSL library. You can find a comprehensive list of commands and their acceptable values in the OpenSSL Documentation, accessible at [OpenSSL Documentation](https://www.openssl.org/docs/man1.0.2/man3/SSL_CONF_cmd.html). + +**General Configuration Guidelines** + +The configuration can be formatted as a single line or across multiple lines. Each command within the configuration is separated by a linefeed (`\n`). To differentiate between a command and its corresponding value, use an equal sign (`=`). Below are some examples to guide you in formatting these commands. + + +Example 1 +--------- + +This will allow all protocols except for SSLv2 and SSLv3: + +.. code-block:: none + + gnutlsPriorityString="Protocol=ALL,-SSLv2,-SSLv3" + + +Example 2 +--------- + +This will allow all protocols except for SSLv2, SSLv3 and TLSv1. +It will also set the minimum protocol to TLSv1.2 + +.. code-block:: none + + gnutlsPriorityString="Protocol=ALL,-SSLv2,-SSLv3,-TLSv1 + MinProtocol=TLSv1.2" + + +PreserveCase +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "boolean", "on", "no", "none" + +.. versionadded:: 8.37.0 + +This parameter is for controlling the case in fromhost. If preservecase is set to "off", the case in fromhost is not preserved. E.g., 'host1.example.org' the message was received from 'Host1.Example.Org'. Default to "on" for the backword compatibility. + + +Input Parameters +---------------- + +Port +^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "yes", "``$InputTCPServerRun``" + +Starts a TCP server on selected port. If port zero is selected, the OS automatically +assigens a free port. Use `listenPortFileName` in this case to obtain the information +of which port was assigned. + + +ListenPortFileName +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +This parameter specifies a file name into which the port number this input listens +on is written. It is primarily intended for cases when `port` is set to 0 to let +the OS automatically assign a free port number. + + +Address +^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +On multi-homed machines, specifies to which local address the +listener should be bound. + + +Name +^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "imtcp", "no", "``$InputTCPServerInputName``" + +Sets a name for the inputname property. If no name is set "imtcp" is +used by default. Setting a name is not strictly necessary, but can be +useful to apply filtering based on which input the message was +received from. + + +Ruleset +^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "``$InputTCPServerBindRuleset``" + +Binds the listener to a specific :doc:`ruleset <../../concepts/multi_ruleset>`. + + +SupportOctetCountedFraming +^^^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "``$InputTCPServerSupportOctetCountedFraming``" + +If set to "on", the legacy octed-counted framing (similar to RFC5425 +framing) is activated. This should be left unchanged until you know +very well what you do. It may be useful to turn it off, if you know +this framing is not used and some senders emit multi-line messages +into the message stream. + + +RateLimit.Interval +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "none" + +Specifies the rate-limiting interval in seconds. Default value is 0, +which turns off rate limiting. Set it to a number of seconds (5 +recommended) to activate rate-limiting. + + +RateLimit.Burst +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "10000", "no", "none" + +Specifies the rate-limiting burst in number of messages. Default is +10,000. + + +listenPortFileName +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +.. versionadded:: 8.38.0 + +With this parameter you can specify the name for a file. In this file the +port, imtcp is connected to, will be written. +This parameter was introduced because the testbench works with dynamic ports. + +.. note:: + + If this parameter is set, 0 will be accepted as the port. Otherwise it + is automatically changed to port 514 + + +StreamDriver.Name +^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "module parameter", "no", "none" + +.. versionadded:: 8.2106.0 + +This permits to override the equally-named module parameter on the input() +level. For further details, see the module parameter. + + +StreamDriver.Mode +^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "module parameter", "no", "``$InputTCPServerStreamDriverMode``" + +.. versionadded:: 8.2106.0 + +This permits to override the equally-named module parameter on the input() +level. For further details, see the module parameter. + + +StreamDriver.AuthMode +^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "module parameter", "no", "``$InputTCPServerStreamDriverAuthMode``" + +.. versionadded:: 8.2106.0 + +This permits to override the equally-named module parameter on the input() +level. For further details, see the module parameter. + + +StreamDriver.PermitExpiredCerts +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "module parameter", "no", "none" + +.. versionadded:: 8.2106.0 + +This permits to override the equally-named module parameter on the input() +level. For further details, see the module parameter. + + +StreamDriver.CheckExtendedKeyPurpose +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "module parameter", "no", "none" + +.. versionadded:: 8.2106.0 + +This permits to override the equally-named module parameter on the input() +level. For further details, see the module parameter. + + +StreamDriver.PrioritizeSAN +^^^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "module parameter", "no", "none" + +.. versionadded:: 8.2106.0 + +This permits to override the equally-named module parameter on the input() +level. For further details, see the module parameter. + + +StreamDriver.TlsVerifyDepth +^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "module parameter", "no", "none" + +.. versionadded:: 8.2106.0 + +This permits to override the equally-named module parameter on the input() +level. For further details, see the module parameter. + + +streamDriver.CAFile +^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "global parameter", "no", "none" + +.. versionadded:: 8.2108.0 + +This permits to override the DefaultNetstreamDriverCAFile global parameter on the input() +level. For further details, see the global parameter. + +streamDriver.CRLFile +^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "optional", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "global parameter", "no", "none" + +.. versionadded:: 8.2308.0 + +This permits to override the CRL (Certificate revocation list) file set via `global()` config +object at the per-action basis. This parameter is ignored if the netstream driver and/or its +mode does not need or support certificates. + +streamDriver.KeyFile +^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "global parameter", "no", "none" + +.. versionadded:: 8.2108.0 + +This permits to override the DefaultNetstreamDriverKeyFile global parameter on the input() +level. For further details, see the global parameter. + + +streamDriver.CertFile +^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "global parameter", "no", "none" + +.. versionadded:: 8.2108.0 + +This permits to override the DefaultNetstreamDriverCertFile global parameter on the input() +level. For further details, see the global parameter. + + +PermittedPeer +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "array", "none", "no", "equally-named module parameter" +.. versionadded:: 8.2112.0 + +This permits to override the equally-named module parameter on the input() +level. For further details, see the module parameter. + + +gnutlsPriorityString +^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "module parameter", "no", "none" +.. versionadded:: 8.2106.0 + +This permits to override the equally-named module parameter on the input() +level. For further details, see the module parameter. + + +MaxSessions +^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "module parameter", "no", "" + +.. versionadded:: 8.2106.0 + +This permits to override the equally-named module parameter on the input() +level. For further details, see the module parameter. + + +MaxListeners +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "module parameter", "no", "" + +.. versionadded:: 8.2106.0 + +This permits to override the equally-named module parameter on the input() +level. For further details, see the module parameter. + + +FlowControl +^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "module parameter", "no", "" + +.. versionadded:: 8.2106.0 + +This permits to override the equally-named module parameter on the input() +level. For further details, see the module parameter. + + +DisableLFDelimiter +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "module parameter", "no", "" + + +.. versionadded:: 8.2106.0 + +This permits to override the equally-named module parameter on the input() +level. For further details, see the module parameter. + + +DiscardTruncatedMsg +^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "module parameter", "no", "none" + +.. versionadded:: 8.2106.0 + +This permits to override the equally-named module parameter on the input() +level. For further details, see the module parameter. + + +NotifyOnConnectionClose +^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "module parameter", "no", "none" + +.. versionadded:: 8.2106.0 + +This permits to override the equally-named module parameter on the input() +level. For further details, see the module parameter. + + +AddtlFrameDelimiter +^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "module parameter", "no", "" + +.. versionadded:: 8.2106.0 + +This permits to override the equally-named module parameter on the input() +level. For further details, see the module parameter. + + +MaxFrameSize +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "module parameter", "no", "none" + +.. versionadded:: 8.2106.0 + +This permits to override the equally-named module parameter on the input() +level. For further details, see the module parameter. + + +PreserveCase +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "boolean", "module parameter", "no", "none" + +.. versionadded:: 8.2106.0 + +This permits to override the equally-named module parameter on the input() +level. For further details, see the module parameter. + + +KeepAlive +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "module parameter", "no", "" + +.. versionadded:: 8.2106.0 + +This permits to override the equally-named module parameter on the input() +level. For further details, see the module parameter. + + +KeepAlive.Probes +^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "module parameter", "no", "" + +.. versionadded:: 8.2106.0 + +This permits to override the equally-named module parameter on the input() +level. For further details, see the module parameter. + + +KeepAlive.Time +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "module parameter", "no", "" + +.. versionadded:: 8.2106.0 + +This permits to override the equally-named module parameter on the input() +level. For further details, see the module parameter. + + +KeepAlive.Interval +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "module parameter", "no", "" + +.. versionadded:: 8.2106.0 + +This permits to override the equally-named module parameter on the input() +level. For further details, see the module parameter. + + + +.. _imtcp-statistic-counter: + +Statistic Counter +================= + +This plugin maintains :doc:`statistics <../rsyslog_statistic_counter>` for each listener. The statistic is named +after the given input name (or "imtcp" if none is configured), followed by +the listener port in parenthesis. For example, the counter for a listener +on port 514 with no set name is called "imtcp(514)". + +The following properties are maintained for each listener: + +- **submitted** - total number of messages submitted for processing since startup + + +Caveats/Known Bugs +================== + +- module always binds to all interfaces +- can not be loaded together with `imgssapi <imgssapi.html>`_ (which + includes the functionality of imtcp) + + +Examples +======== + +Example 1 +--------- + +This sets up a TCP server on port 514 and permits it to accept up to 500 +connections: + +.. code-block:: none + + module(load="imtcp" MaxSessions="500") + input(type="imtcp" port="514") + + +Note that the global parameters (here: max sessions) need to be set when +the module is loaded. Otherwise, the parameters will not apply. + + +Additional Resources +==================== + +- `rsyslog video tutorial on how to store remote messages in a separate file <http://www.rsyslog.com/howto-store-remote-messages-in-a-separate-file/>`_ (for legacy syntax, but you get the idea). + diff --git a/source/configuration/modules/imtuxedoulog.rst b/source/configuration/modules/imtuxedoulog.rst new file mode 100644 index 0000000..56f72a9 --- /dev/null +++ b/source/configuration/modules/imtuxedoulog.rst @@ -0,0 +1,146 @@ +************************************** +imtuxedoulog: Tuxedo ULOG input module +************************************** + +================ ============================================================== +**Module Name:** **imtuxedoulog** +**Authors:** Jean-Philippe Hilaire <jean-philippe.hilaire@pmu.fr> & Philippe Duveau <philippe.duveau@free.fr> +================ ============================================================== + + +Purpose +======= + +This module allows rsyslog to process Tuxedo ULOG files. +Tuxedo create an ULOG file each new log of the day this file is defined + +- a prefix configured in the tuxedo configuration + +- a suffix based on the date ".MMDDYY" + +This module is a copy of the polling mode of imfile but the file name is +computed each polling. The previous one is closed to limit the number of +opened file descriptor simultaneously. + +Another particularity of ULOG is that the lines contains only the time in +day. So the module use the date in filename and time in log to fill log +timestamp. + +Compile +======= + +To successfully compile improg module. + + ./configure --enable-imtuxedoulog ... + +Configuration Parameters +======================== + +Action Parameters +----------------- + +ulogbase +^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "yes", "path of ULOG file", + +Path of ULOG file as it is defined in Tuxedo Configuration ULOGPFX. +Dot and date is added a end to build full file path + +Tag +^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "yes", ,"none" + +The tag to be assigned to messages read from this file. If you would like to +see the colon after the tag, you need to include it when you assign a tag +value, like so: ``tag="myTagValue:"``. + +Facility +^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "no", "facility\|number", "local0" + +The syslog facility to be assigned to messages read from this file. Can be +specified in textual form (e.g. ``local0``, ``local1``, ...) or as numbers (e.g. +16 for ``local0``). Textual form is suggested. + +Severity +^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "no", "severity\|number", "notice" + +The syslog severity to be assigned to lines read. Can be specified +in textual form (e.g. ``info``, ``warning``, ...) or as numbers (e.g. 6 +for ``info``). Textual form is suggested. + +PersistStateInterval +^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", + +Specifies how often the state file shall be written when processing +the input file. The **default** value is 0, which means a new state +file is only written when the monitored files is being closed (end of +rsyslogd execution). Any other value n means that the state file is +written every time n file lines have been processed. This setting can +be used to guard against message duplication due to fatal errors +(like power fail). Note that this setting affects imfile performance, +especially when set to a low value. Frequently writing the state file +is very time consuming. + +MaxLinesAtOnce +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", + +If set to 0, the file will be fully processed. If it is set to any other +value, a maximum of [number] lines is processed in sequence. The **default** +is 10240. + +MaxSubmitAtOnce +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "1024", "no", "none" + +This is an expert option. It can be used to set the maximum input +batch size that the module can generate. The **default** is 1024, which +is suitable for a wide range of applications. Be sure to understand +rsyslog message batch processing before you modify this option. If +you do not know what this doc here talks about, this is a good +indication that you should NOT modify the default. diff --git a/source/configuration/modules/imudp.rst b/source/configuration/modules/imudp.rst new file mode 100644 index 0000000..cfaf9e6 --- /dev/null +++ b/source/configuration/modules/imudp.rst @@ -0,0 +1,600 @@ +****************************** +imudp: UDP Syslog Input Module +****************************** + +.. index:: ! imudp + +=========================== =========================================================================== +**Module Name:** **imudp** +**Author:** `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com> +=========================== =========================================================================== + + +Purpose +======= + +Provides the ability to receive syslog messages via UDP. + +Multiple receivers may be configured by specifying multiple input +statements. + +Note that in order to enable UDP reception, Firewall rules probably +need to be modified as well. Also, SELinux may need additional rules. + + +Notable Features +================ + +- :ref:`imudp-statistic-counter` + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + +.. index:: imudp; module parameters + + +Module Parameters +----------------- + +TimeRequery +^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "2", "no", "``$UDPServerTimeRequery``" + +This is a performance optimization. Getting the system time is very +costly. With this setting, imudp can be instructed to obtain the +precise time only once every n-times. This logic is only activated if +messages come in at a very fast rate, so doing less frequent time +calls should usually be acceptable. The default value is two, because +we have seen that even without optimization the kernel often returns +twice the identical time. You can set this value as high as you like, +but do so at your own risk. The higher the value, the less precise +the timestamp. + +**Note:** the timeRequery is done based on executed system calls +(**not** messages received). So when batch sizes are used, multiple +messages are received with one system call. All of these messages +always receive the same timestamp, as they are effectively received +at the same time. When there is very high traffic and successive +system calls immediately return the next batch of messages, the time +requery logic kicks in, which means that by default time is only +queried for every second batch. Again, this should not cause a +too-much deviation as it requires messages to come in very rapidly. +However, we advise not to set the "timeRequery" parameter to a large +value (larger than 10) if input batches are used. + + +SchedulingPolicy +^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "``$IMUDPSchedulingPolicy``" + +Can be used the set the scheduler priority, if the necessary +functionality is provided by the platform. Most useful to select +"fifo" for real-time processing under Linux (and thus reduce chance +of packet loss). Other options are "rr" and "other". + + +SchedulingPriority +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "none", "no", "``$IMUDPSchedulingPriority``" + +Scheduling priority to use. + + +BatchSize +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "32", "no", "none" + +This parameter is only meaningful if the system support recvmmsg() +(newer Linux OSs do this). The parameter is silently ignored if the +system does not support it. If supported, it sets the maximum number +of UDP messages that can be obtained with a single OS call. For +systems with high UDP traffic, a relatively high batch size can +reduce system overhead and improve performance. However, this +parameter should not be overdone. For each buffer, max message size +bytes are statically required. Also, a too-high number leads to +reduced efficiency, as some structures need to be completely +initialized before the OS call is done. We would suggest to not set +it above a value of 128, except if experimental results show that +this is useful. + + +Threads +^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "1", "no", "none" + +.. versionadded:: 7.5.5 + +Number of worker threads to process incoming messages. These threads +are utilized to pull data off the network. On a busy system, +additional threads (but not more than there are CPUs/Cores) can help +improving performance and avoiding message loss. Note that with too +many threads, performance can suffer. There is a hard upper limit on +the number of threads that can be defined. Currently, this limit is +set to 32. It may increase in the future when massive multicore +processors become available. + + +PreserveCase +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "boolean", "off", "no", "none" + +.. versionadded:: 8.37.0 + +This parameter is for controlling the case in fromhost. If preservecase is set to "on", the case in fromhost is preserved. E.g., 'Host1.Example.Org' when the message was received from 'Host1.Example.Org'. Default to "off" for the backword compatibility. + + +.. index:: imudp; input parameters + + +Input Parameters +---------------- + +.. index:: imudp; address (input parameter) + +Address +^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "``$UDPServerAddress``" + +Local IP address (or name) the UDP server should bind to. Use "*" +to bind to all of the machine's addresses. + + +Port +^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "array", "514", "yes", "``$UDPServerRun``" + +Specifies the port the server shall listen to.. Either a single port can +be specified or an array of ports. If multiple ports are specified, a +listener will be automatically started for each port. Thus, no +additional inputs need to be configured. + +Single port: Port="514" + +Array of ports: Port=["514","515","10514","..."] + + +IpFreeBind +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "2", "no", "none" + +.. versionadded:: 8.18.0 + +Manages the IP_FREEBIND option on the UDP socket, which allows binding it to +an IP address that is nonlocal or not (yet) associated to any network interface. + +The parameter accepts the following values: + +- 0 - does not enable the IP_FREEBIND option on the + UDP socket. If the *bind()* call fails because of *EADDRNOTAVAIL* error, + socket initialization fails. + +- 1 - silently enables the IP_FREEBIND socket + option if it is required to successfully bind the socket to a nonlocal address. + +- 2 - enables the IP_FREEBIND socket option and + warns when it is used to successfully bind the socket to a nonlocal address. + + +Device +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +Bind socket to given device (e.g., eth0) + +For Linux with VRF support, the Device option can be used to specify the +VRF for the Address. + + +Ruleset +^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "RSYSLOG_DefaultRuleset", "no", "``$InputUDPServerBindRuleset``" + +Binds the listener to a specific :doc:`ruleset <../../concepts/multi_ruleset>`. + + +RateLimit.Interval +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "none" + +.. versionadded:: 7.3.1 + +The rate-limiting interval in seconds. Value 0 turns off rate limiting. +Set it to a number of seconds (5 recommended) to activate rate-limiting. + + +RateLimit.Burst +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "10000", "no", "none" + +.. versionadded:: 7.3.1 + +Specifies the rate-limiting burst in number of messages. + + +Name +^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "imudp", "no", "none" + +.. versionadded:: 8.3.3 + +Specifies the value of the inputname property. In older versions, +this was always "imudp" for all +listeners, which still is the default. Starting with 7.3.9 it can be +set to different values for each listener. Note that when a single +input statement defines multiple listener ports, the inputname will be +the same for all of them. If you want to differentiate in that case, +use "name.appendPort" to make them unique. Note that the +"name" parameter can be an empty string. In that case, the +corresponding inputname property will obviously also be the empty +string. This is primarily meant to be used together with +"name.appendPort" to set the inputname equal to the port. + + +Name.appendPort +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +.. versionadded:: 7.3.9 + +Appends the port the inputname property. Note that when no "name" is +specified, the default of "imudp" is used and the port is appended to +that default. So, for example, a listener port of 514 in that case +will lead to an inputname of "imudp514". The ability to append a port +is most useful when multiple ports are defined for a single input and +each of the inputnames shall be unique. Note that there currently is +no differentiation between IPv4/v6 listeners on the same port. + + +DefaultTZ +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +This is an **experimental** parameter; details may change at any +time and it may also be discontinued without any early warning. +Permits to set a default timezone for this listener. This is useful +when working with legacy syslog (RFC3164 et al) residing in different +timezones. If set it will be used as timezone for all messages **that +do not contain timezone info**. Currently, the format **must** be +"+/-hh:mm", e.g. "-05:00", "+01:30". Other formats, including TZ +names (like EST) are NOT yet supported. Note that consequently no +daylight saving settings are evaluated when working with timezones. +If an invalid format is used, "interesting" things can happen, among +them malformed timestamps and rsyslogd segfaults. This will obviously +be changed at the time this feature becomes non-experimental. + + +RcvBufSize +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "size", "none", "no", "none" + +.. versionadded:: 7.3.9 + +This request a socket receive buffer of specific size from the operating system. It +is an expert parameter, which should only be changed for a good reason. +Note that setting this parameter disables Linux auto-tuning, which +usually works pretty well. The default value is 0, which means "keep +the OS buffer size unchanged". This is a size value. So in addition +to pure integer values, sizes like "256k", "1m" and the like can be +specified. Note that setting very large sizes may require root or +other special privileges. Also note that the OS may slightly adjust +the value or shrink it to a system-set max value if the user is not +sufficiently privileged. Technically, this parameter will result in a +setsockopt() call with SO\_RCVBUF (and SO\_RCVBUFFORCE if it is +available). (Maximum Value: 1G) + + +.. _imudp-statistic-counter: + +Statistic Counter +================= + +This plugin maintains :doc:`statistics <../rsyslog_statistic_counter>` for each listener and for each worker thread. + +The listener statistic is named starting with "imudp", followed followed by the +listener IP, a colon and port in parenthesis. For example, the counter for a +listener on port 514 (on all IPs) with no set name is called "imudp(\*:514)". + +If an "inputname" is defined for a listener, that inputname is used instead of +"imudp" as statistic name. For example, if the inputname is set to "myudpinut", +that corresponding statistic name in above case would be "myudpinput(\*:514)". +This has been introduced in 7.5.3. + +The following properties are maintained for each listener: + +- **submitted** - total number of messages submitted for processing since startup + +The worker thread (in short: worker) statistic is named "imudp(wX)" where "X" is +the worker thread ID, which is an monotonically increasing integer starting at 0. +This means the first worker will have the name "imudp(w0)", the second "imudp(w1)" +and so on. Note that workers are all equal. It doesn’t really matter which worker +processes which messages, so the actual worker ID is not of much concern. More +interesting is to check how the load is spread between the worker. Also note that +there is no fixed worker-to-listener relationship: all workers process messages +from all listeners. + +Note: worker thread statistics are available starting with rsyslog 7.5.5. + +- **disallowed** - total number of messages discarded due to disallowed sender + +This counts the number of messages that have been discarded because they have +been received by an disallowed sender. Note that if no allowed senders are +configured (the default), this counter will always be zero. + +This counter was introduced by rsyslog 8.35.0. + + +The following properties are maintained for each worker thread: + +- **called.recvmmsg** - number of recvmmsg() OS calls done + +- **called.recvmsg** - number of recvmsg() OS calls done + +- **msgs.received** - number of actual messages received + + +Caveats/Known Bugs +================== + +- Scheduling parameters are set **after** privileges have been dropped. + In most cases, this means that setting them will not be possible + after privilege drop. This may be worked around by using a + sufficiently-privileged user account. + +Examples +======== + +Example 1 +--------- + +This sets up an UDP server on port 514: + +.. code-block:: none + + module(load="imudp") # needs to be done just once + input(type="imudp" port="514") + + +Example 2 +--------- + +This sets up a UDP server on port 514 bound to device eth0: + +.. code-block:: none + + module(load="imudp") # needs to be done just once + input(type="imudp" port="514" device="eth0") + + +Example 3 +--------- + +The following sample is mostly equivalent to the first one, but request +a larger rcvuf size. Note that 1m most probably will not be honored by +the OS until the user is sufficiently privileged. + +.. code-block:: none + + module(load="imudp") # needs to be done just once + input(type="imudp" port="514" rcvbufSize="1m") + + +Example 4 +--------- + +In the next example, we set up three listeners at ports 10514, 10515 and +10516 and assign a listener name of "udp" to it, followed by the port +number: + +.. code-block:: none + + module(load="imudp") + input(type="imudp" port=["10514","10515","10516"] + inputname="udp" inputname.appendPort="on") + + +Example 5 +--------- + +The next example is almost equal to the previous one, but now the +inputname property will just be set to the port number. So if a message +was received on port 10515, the input name will be "10515" in this +example whereas it was "udp10515" in the previous one. Note that to do +that we set the inputname to the empty string. + +.. code-block:: none + + module(load="imudp") + input(type="imudp" port=["10514","10515","10516"] + inputname="" inputname.appendPort="on") + + +Additional Information on Performance Tuning +============================================ + +Threads and Ports +----------------- + +The maximum number of threads is a module parameter. Thus there is no direct +relation to the number of ports. + +Every worker thread processes all inbound ports in parallel. To do so, it +adds all listen ports to an `epoll()` set and waits for packets to arrive. If +the system supports the `recvmmsg()` call, it tries to receive up to `batchSize` +messages at once. This reduces the number of transitions between user and +kernel space and as such overhead. + +After the packages have been received, imudp processes each message and creates +input batches which are then submitted according to the config file's queue +definition. After that the a new cycle beings and imudp return to wait for +new packets to arrive. + +When multiple threads are defined, each thread performs the processing +described above. All worker threads are created when imudp is started. +Each of them will individually awoken from epoll as data +is present. Each one reads as much available data as possible. With a low +incoming volume this can be inefficient in that the threads compete against +inbound data. At sufficiently high volumes this is not a problem because +multiple workers permit to read data from the operating system buffers +while other workers process the data they have read. It must be noted +that "sufficiently high volume" is not a precise concept. A single thread +can be very efficient. As such it is recommended to run impstats inside a +performance testing lab to find out a good number of worker threads. If +in doubt, start with a low number and increase only if performance +actually increases by adding threads. + +A word of caution: just looking at thread CPU use is **not** a proper +way to monitor imudp processing capabilities. With too many threads +the overhead can increase, even strongly. This can result in a much higher +CPU utilization but still overall less processing capability. + +Please also keep in your mind that additional input worker threads may +cause more mutex contention when adding data to processing queues. + +Too many threads may also reduce the number of messages received via +a single recvmmsg() call, which in turn increases kernel/user space +switching and thus system overhead. + +If **real time** priority is used it must be ensured that not all +operating system cores are used by imudp threads. The reason is that +otherwise for heavy workloads there is no ability to actually process +messages. While this may be desirable in some cases where queue settings +permit for large bursts, it in general can lead to pushback from the +queues. + +For lower volumes, real time priority can increase the operating system +overhead by awaking imudp more often than strictly necessary and thus +reducing the effectiveness of `recvmmsg()`. + +imudp threads and queue worker threads +-------------------------------------- +There is no direct relationship between these two entities. Imudp submits +messages to the configured rulesets and places them into the respective +queues. It is then up the the queue config, and outside of the scope +or knowledge of imudp, how many queue worker threads will be spawned by +the queue in question. + +Note, however, that queue worker threads and imudp input worker threads +compete for system resources. As such the combined overall value should +not overload the system. There is no strict rule to follow when sizing +overall worker numbers: for queue workers it strongly depends on how +compute-intense the workload is. For example, omfile actions need +few worker threads as they are fast. On the contrary, omelasticsearch often +waits for server replies and as such more worker threads can be beneficial. +The queue subsystem auto-tuning of worker threads should handle the +different needs in a useful way. + +Additional Resources +==================== + +- `rsyslog video tutorial on how to store remote messages in a separate file <http://www.rsyslog.com/howto-store-remote-messages-in-a-separate-file/>`_. +- Description of `rsyslog statistic + counters <http://www.rsyslog.com/rsyslog-statistic-counter/>`_. + This also describes all imudp counters. + diff --git a/source/configuration/modules/imuxsock.rst b/source/configuration/modules/imuxsock.rst new file mode 100644 index 0000000..8c05108 --- /dev/null +++ b/source/configuration/modules/imuxsock.rst @@ -0,0 +1,966 @@ +********************************** +imuxsock: Unix Socket Input Module +********************************** + +=========================== =========================================================================== +**Module Name:** **imuxsock** +**Author:** `Rainer Gerhards <http://www.gerhards.net/rainer>`_ <rgerhards@adiscon.com> +=========================== =========================================================================== + + +Purpose +======= + +This module provides the ability to accept syslog messages from applications +running on the local system via Unix sockets. Most importantly, this is the +mechanism by which the :manpage:`syslog(3)` call delivers syslog messages +to rsyslogd. + +.. seealso:: + + :doc:`omuxsock` + + +Notable Features +================ + +- :ref:`imuxsock-rate-limiting-label` +- :ref:`imuxsock-trusted-properties-label` +- :ref:`imuxsock-flow-control-label` +- :ref:`imuxsock-application-timestamps-label` +- :ref:`imuxsock-systemd-details-label` + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + +Module Parameters +----------------- + +.. warning:: + + When running under systemd, **many "sysSock." parameters are ignored**. + See parameter descriptions and the :ref:`imuxsock-systemd-details-label` section for + details. + + +SysSock.IgnoreTimestamp +^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "``$SystemLogSocketIgnoreMsgTimestamp``" + +Ignore timestamps included in the messages, applies to messages received via +the system log socket. + + +SysSock.IgnoreOwnMessages +^^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "none" + +Ignores messages that originated from the same instance of rsyslogd. +There usually is no reason to receive messages from ourselves. This +setting is vital when writing messages to the systemd journal. + +.. versionadded:: 7.3.7 + +.. seealso:: + + See :doc:`omjournal <omjournal>` module documentation for a more + in-depth description. + + +SysSock.Use +^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "``$OmitLocalLogging``" + +Listen on the default local log socket (``/dev/log``) or, if provided, use +the log socket value assigned to the ``SysSock.Name`` parameter instead +of the default. This is most useful if you run multiple instances of +rsyslogd where only one shall handle the system log socket. Unless +disabled by the ``SysSock.Unlink`` setting, this socket is created +upon rsyslog startup and deleted upon shutdown, according to +traditional syslogd behavior. + +The behavior of this parameter is different for systemd systems. For those +systems, ``SysSock.Use`` still needs to be enabled, but the value of +``SysSock.Name`` is ignored and the socket provided by systemd is used +instead. If this parameter is *not* enabled, then imuxsock will only be +of use if a custom input is configured. + +See the :ref:`imuxsock-systemd-details-label` section for details. + + +SysSock.Name +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "/dev/log", "no", "``$SystemLogSocketName``" + +Specifies an alternate log socket to be used instead of the default system +log socket, traditionally ``/dev/log``. Unless disabled by the +``SysSock.Unlink`` setting, this socket is created upon rsyslog startup +and deleted upon shutdown, according to traditional syslogd behavior. + +The behavior of this parameter is different for systemd systems. See the + :ref:`imuxsock-systemd-details-label` section for details. + + +SysSock.FlowControl +^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "``$SystemLogFlowControl``" + +Specifies if flow control should be applied to the system log socket. + + +SysSock.UsePIDFromSystem +^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "``$SystemLogUsePIDFromSystem``" + +Specifies if the pid being logged shall be obtained from the log socket +itself. If so, the TAG part of the message is rewritten. It is recommended +to turn this option on, but the default is "off" to keep compatible +with earlier versions of rsyslog. + +.. versionadded:: 5.7.0 + + +SysSock.RateLimit.Interval +^^^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "max", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "", "no", "``$SystemLogRateLimitInterval``" + +Specifies the rate-limiting interval in seconds. Default value is 0, +which turns off rate limiting. Set it to a number of seconds (5 +recommended) to activate rate-limiting. The default of 0 has been +chosen as people experienced problems with this feature activated +by default. Now it needs an explicit opt-in by setting this parameter. + + +SysSock.RateLimit.Burst +^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "max", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "200", "(2^31)-1", "no", "``$SystemLogRateLimitBurst``" + +Specifies the rate-limiting burst in number of messages. + +.. versionadded:: 5.7.1 + + +SysSock.RateLimit.Severity +^^^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "max", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "1", "", "no", "``$SystemLogRateLimitSeverity``" + +Specifies the severity of messages that shall be rate-limited. + +.. seealso:: + + https://en.wikipedia.org/wiki/Syslog#Severity_level + + +SysSock.UseSysTimeStamp +^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "``$SystemLogUseSysTimeStamp``" + +The same as the input parameter ``UseSysTimeStamp``, but for the system log +socket. This parameter instructs ``imuxsock`` to obtain message time from +the system (via control messages) instead of using time recorded inside +the message. This may be most useful in combination with systemd. Due to +the usefulness of this functionality, we decided to enable it by default. +As such, the behavior is slightly different than previous versions. +However, we do not see how this could negatively affect existing environments. + +.. versionadded:: 5.9.1 + + +SysSock.Annotate +^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "``$SystemLogSocketAnnotate``" + +Turn on annotation/trusted properties for the system log socket. See +the :ref:`imuxsock-trusted-properties-label` section for more info. + + +SysSock.ParseTrusted +^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "``$SystemLogParseTrusted``" + +If ``SysSock.Annotation`` is turned on, create JSON/lumberjack properties +out of the trusted properties (which can be accessed via |FmtAdvancedName| +JSON Variables, e.g. ``$!pid``) instead of adding them to the message. + +.. versionadded:: 7.2.7 + |FmtAdvancedName| directive introduced + +.. versionadded:: 7.3.8 + |FmtAdvancedName| directive introduced + +.. versionadded:: 6.5.0 + |FmtObsoleteName| directive introduced + + +SysSock.Unlink +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "none" + +If turned on (default), the system socket is unlinked and re-created +when opened and also unlinked when finally closed. Note that this +setting has no effect when running under systemd control (because +systemd handles the socket. See the :ref:`imuxsock-systemd-details-label` +section for details. + +.. versionadded:: 7.3.9 + + +SysSock.UseSpecialParser +^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "none" + +The equivalent of the ``UseSpecialParser`` input parameter, but +for the system socket. If turned on (the default) a special parser is +used that parses the format that is usually used +on the system log socket (the one :manpage:`syslog(3)` creates). If set to +"off", the regular parser chain is used, in which case the format on the +log socket can be arbitrary. + +.. note:: + + When the special parser is used, rsyslog is able to inject a more precise + timestamp into the message (it is obtained from the log socket). If the + regular parser chain is used, this is not possible. + +.. versionadded:: 8.9.0 + The setting was previously hard-coded "on" + + +SysSock.ParseHostname +^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +.. note:: + + This option only has an effect if ``SysSock.UseSpecialParser`` is + set to "off". + +Normally, the local log sockets do *not* contain hostnames. If set +to on, parsers will expect hostnames just like in regular formats. If +set to off (the default), the parser chain is instructed to not expect +them. + +.. versionadded:: 8.9.0 + + +Input Parameters +---------------- + +Ruleset +^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "default ruleset", "no", "none" + +Binds specified ruleset to this input. If not set, the default +ruleset is bound. + +.. versionadded:: 8.17.0 + + +IgnoreTimestamp +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "``$InputUnixListenSocketIgnoreMsgTimestamp``" + +Ignore timestamps included in messages received from the input being +defined. + + +IgnoreOwnMessages +^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "none" + +Ignore messages that originated from the same instance of rsyslogd. +There usually is no reason to receive messages from ourselves. This +setting is vital when writing messages to the systemd journal. + +.. versionadded:: 7.3.7 + +.. seealso:: + + See :doc:`omjournal <omjournal>` module documentation for a more + in-depth description. + + + + +FlowControl +^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "``$InputUnixListenSocketFlowControl``" + +Specifies if flow control should be applied to the input being defined. + + +RateLimit.Interval +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "max", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "", "no", "``$IMUXSockRateLimitInterval``" + +Specifies the rate-limiting interval in seconds. Default value is 0, which +turns off rate limiting. Set it to a number of seconds (5 recommended) +to activate rate-limiting. The default of 0 has been chosen as people +experienced problems with this feature activated by default. Now it +needs an explicit opt-in by setting this parameter. + + +RateLimit.Burst +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "max", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "200", "(2^31)-1", "no", "``$IMUXSockRateLimitBurst``" + +Specifies the rate-limiting burst in number of messages. + +.. versionadded:: 5.7.1 + + +RateLimit.Severity +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "max", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "1", "", "no", "``$IMUXSockRateLimitSeverity``" + +Specifies the severity of messages that shall be rate-limited. + +.. seealso:: + + https://en.wikipedia.org/wiki/Syslog#Severity_level + + +UsePIDFromSystem +^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "``$InputUnixListenSocketUsePIDFromSystem``" + +Specifies if the pid being logged shall be obtained from the log socket +itself. If so, the TAG part of the message is rewritten. It is +recommended to turn this option on, but the default is "off" to keep +compatible with earlier versions of rsyslog. + + +UseSysTimeStamp +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "``$InputUnixListenSocketUseSysTimeStamp``" + +This parameter instructs ``imuxsock`` to obtain message time from +the system (via control messages) instead of using time recorded inside +the message. This may be most useful in combination with systemd. Due to +the usefulness of this functionality, we decided to enable it by default. +As such, the behavior is slightly different than previous versions. +However, we do not see how this could negatively affect existing environments. + +.. versionadded:: 5.9.1 + + +CreatePath +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "``$InputUnixListenSocketCreatePath``" + +Create directories in the socket path if they do not already exist. +They are created with 0755 permissions with the owner being the +process under which rsyslogd runs. The default is not to create +directories. Keep in mind, though, that rsyslogd always creates +the socket itself if it does not exist (just not the directories +by default). + +This option is primarily considered useful for defining additional +sockets that reside on non-permanent file systems. As rsyslogd probably +starts up before the daemons that create these sockets, it is a vehicle +to enable rsyslogd to listen to those sockets even though their directories +do not yet exist. + +.. versionadded:: 4.7.0 +.. versionadded:: 5.3.0 + + +Socket +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "``$AddUnixListenSocket``" + +Adds additional unix socket. Formerly specified with the ``-a`` option. + + +HostName +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "NULL", "no", "``$InputUnixListenSocketHostName``" + +Allows overriding the hostname that shall be used inside messages +taken from the input that is being defined. + + +Annotate +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "``$InputUnixListenSocketAnnotate``" + +Turn on annotation/trusted properties for the input that is being defined. +See the :ref:`imuxsock-trusted-properties-label` section for more info. + + +ParseTrusted +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "``$ParseTrusted``" + +Equivalent to the ``SysSock.ParseTrusted`` module parameter, but applies +to the input that is being defined. + + +Unlink +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "``none``" + +If turned on (default), the socket is unlinked and re-created when opened +and also unlinked when finally closed. Set it to off if you handle socket +creation yourself. + +.. note:: + + Note that handling socket creation oneself has the + advantage that a limited amount of messages may be queued by the OS + if rsyslog is not running. + +.. versionadded:: 7.3.9 + + +UseSpecialParser +^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "none" + +Equivalent to the ``SysSock.UseSpecialParser`` module parameter, but applies +to the input that is being defined. + +.. versionadded:: 8.9.0 + The setting was previously hard-coded "on" + + +ParseHostname +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +Equivalent to the ``SysSock.ParseHostname`` module parameter, but applies +to the input that is being defined. + +.. versionadded:: 8.9.0 + + +.. _imuxsock-rate-limiting-label: + +Input rate limiting +=================== + +rsyslog supports (optional) input rate limiting to guard against the problems +of a wild running logging process. If more than +``SysSock.RateLimit.Interval`` \* ``SysSock.RateLimit.Burst`` log messages +are emitted from the same process, those messages with +``SysSock.RateLimit.Severity`` or lower will be dropped. It is not possible +to recover anything about these messages, but imuxsock will tell you how +many it has dropped once the interval has expired AND the next message is +logged. Rate-limiting depends on ``SCM\_CREDENTIALS``. If the platform does +not support this socket option, rate limiting is turned off. If multiple +sockets are configured, rate limiting works independently on each of +them (that should be what you usually expect). + +The same functionality is available for additional log sockets, in which +case the config statements just use the prefix RateLimit... but otherwise +works exactly the same. When working with severities, please keep in mind +that higher severity numbers mean lower severity and configure things +accordingly. To turn off rate limiting, set the interval to zero. + +.. versionadded:: 5.7.1 + + +.. _imuxsock-trusted-properties-label: + +Trusted (syslog) properties +=========================== + +rsyslog can annotate messages from system log sockets (via imuxsock) with +so-called `Trusted syslog +properties <http://www.rsyslog.com/what-are-trusted-properties/>`_, (or just +"Trusted Properties" for short). These are message properties not provided by +the logging client application itself, but rather obtained from the system. +As such, they can not be faked by the user application and are trusted in +this sense. This feature is based on a similar idea introduced in systemd. + +This feature requires a recent enough Linux Kernel and access to +the ``/proc`` file system. In other words, this may not work on all +platforms and may not work fully when privileges are dropped (depending +on how they are dropped). Note that trusted properties can be very +useful, but also typically cause the message to grow rather large. Also, +the format of log messages is changed by adding the trusted properties at +the end. For these reasons, the feature is **not enabled by default**. +If you want to use it, you must turn it on (via +``SysSock.Annotate`` and ``Annotate``). + +.. versionadded:: 5.9.4 + +.. seealso:: + + `What are "trusted properties"? + <http://www.rsyslog.com/what-are-trusted-properties/>`_ + + +.. _imuxsock-flow-control-label: + +Flow-control of Unix log sockets +================================ + +If processing queues fill up, the unix socket reader is blocked for a +short while to help prevent overrunning the queues. If the queues are +overrun, this may cause excessive disk-io and impact performance. + +While turning on flow control for many systems does not hurt, it `can` lead +to a very unresponsive system and as such is disabled by default. + +This means that log records are placed as quickly as possible into the +processing queues. If you would like to have flow control, you +need to enable it via the ``SysSock.FlowControl`` and ``FlowControl`` config +directives. Just make sure you have thought about the implications and have +tested the change on a non-production system first. + + +.. _imuxsock-application-timestamps-label: + +Control over application timestamps +=================================== + +Application timestamps are ignored by default. This is needed, as some +programs (e.g. sshd) log with inconsistent timezone information, what +messes up the local logs (which by default don't even contain time zone +information). This seems to be consistent with what sysklogd has done for +many years. Alternate behaviour may be desirable if gateway-like processes +send messages via the local log slot. In that case, it can be enabled via +the ``SysSock.IgnoreTimestamp`` and ``IgnoreTimestamp`` config directives. + + +.. _imuxsock-systemd-details-label: + +Coexistence with systemd +======================== + +Rsyslog should by default be configured for systemd support on all platforms +that usually run systemd (which means most Linux distributions, but not, for +example, Solaris). + +Rsyslog is able to coexist with systemd with minimal changes on the part of the +local system administrator. While the ``systemd journal`` now assumes full +control of the local ``/dev/log`` system log socket, systemd provides +access to logging data via the ``/run/systemd/journal/syslog`` log socket. +This log socket is provided by the ``syslog.socket`` file that is shipped +with systemd. + +The imuxsock module can still be used in this setup and provides superior +performance over :doc:`imjournal <imjournal>`, the alternative journal input +module. + +.. note:: + + It must be noted, however, that the journal tends to drop messages + when it becomes busy instead of forwarding them to the system log socket. + This is because the journal uses an async log socket interface for forwarding + instead of the traditional synchronous one. + +.. versionadded:: 8.32.0 + rsyslog emits an informational message noting the system log socket provided + by systemd. + +.. seealso:: + + :doc:`imjournal` + + +Handling of sockets +------------------- + +What follows is a brief description of the process rsyslog takes to determine +what system socket to use, which sockets rsyslog should listen on, whether +the sockets should be created and how rsyslog should handle the sockets when +shutting down. + +.. seealso:: + + `Writing syslog Daemons Which Cooperate Nicely With systemd + <https://www.freedesktop.org/wiki/Software/systemd/syslog/>`_ + + +Step 1: Select name of system socket +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +#. If the user has not explicitly chosen to set ``SysSock.Use="off"`` then + the default listener socket (aka, "system log socket" or simply "system + socket") name is set to ``/dev/log``. Otherwise, if the user `has` + explicitly set ``SysSock.Use="off"``, then rsyslog will not listen on + ``/dev/log`` OR any socket defined by the ``SysSock.Name`` parameter and + the rest of this section does not apply. + +#. If the user has specified ``sysSock.Name="/path/to/custom/socket"`` (and not + explicitly set ``SysSock.Use="off"``), then the default listener socket name + is overwritten with ``/path/to/custom/socket``. + +#. Otherwise, if rsyslog is running under systemd AND + ``/run/systemd/journal/syslog`` exists, (AND the user has not + explicitly set ``SysSock.Use="off"``) then the default listener socket name + is overwritten with ``/run/systemd/journal/syslog``. + + +Step 2: Listen on specified sockets +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +.. note:: + + This is true for all sockets, be it system socket or not. But if + ``SysSock.Use="off"``, the system socket will not be listened on. + +rsyslog evaluates the list of sockets it has been asked to activate: + +- the system log socket (if still enabled after completion of the last section) +- any custom inputs defined by the user + +and then checks to see if it has been passed in via systemd (name is checked). +If it was passed in via systemd, the socket is used as-is (e.g., not recreated +upon rsyslog startup), otherwise if not passed in via systemd the log socket +is unlinked, created and opened. + + +Step 3: Shutdown log sockets +^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +.. note:: + + This is true for all sockets, be it system socket or not. + +Upon shutdown, rsyslog processes each socket it is listening on and evaluates +it. If the socket was originally passed in via systemd (name is checked), then +rsyslog does nothing with the socket (systemd maintains the socket). + +If the socket was `not` passed in via systemd AND the configuration permits +rsyslog to do so (the default setting), rsyslog will unlink/remove the log +socket. If not permitted to do so (the user specified otherwise), then rsyslog +will not unlink the log socket and will leave that cleanup step to the +user or application that created the socket to remove it. + + +Statistic Counter +================= + +This plugin maintains a global :doc:`statistics <../rsyslog_statistic_counter>` with the following properties: + +- ``submitted`` - total number of messages submitted for processing since startup + +- ``ratelimit.discarded`` - number of messages discarded due to rate limiting + +- ``ratelimit.numratelimiters`` - number of currently active rate limiters + (small data structures used for the rate limiting logic) + + +Caveats/Known Bugs +================== + +- When running under systemd, **many "sysSock." parameters are ignored**. + See parameter descriptions and the :ref:`imuxsock-systemd-details-label` section for + details. + +- On systems where systemd is used this module is often not loaded by default. + See the :ref:`imuxsock-systemd-details-label` section for details. + +- Application timestamps are ignored by default. See the + :ref:`imuxsock-application-timestamps-label` section for details. + +- `imuxsock does not work on Solaris + <http://www.rsyslog.com/why-does-imuxsock-not-work-on-solaris/>`_ + +.. todolist:: + + +Examples +======== + +Minimum setup +------------- + +The following sample is the minimum setup required to accept syslog +messages from applications running on the local system. + +.. code-block:: none + + module(load="imuxsock") + +This only needs to be done once. + + +Enable flow control +------------------- + +.. code-block:: none + :emphasize-lines: 2 + + module(load="imuxsock" # needs to be done just once + SysSock.FlowControl="on") # enable flow control (use if needed) + +Enable trusted properties +------------------------- + +As noted in the :ref:`imuxsock-trusted-properties-label` section, trusted properties +are disabled by default. If you want to use them, you must turn the feature +on via ``SysSock.Annotate`` for the system log socket and ``Annotate`` for +inputs. + +Append to end of message +^^^^^^^^^^^^^^^^^^^^^^^^ + +The following sample is used to activate message annotation and thus +trusted properties on the system log socket. These trusted properties +are appended to the end of each message. + +.. code-block:: none + :emphasize-lines: 2 + + module(load="imuxsock" # needs to be done just once + SysSock.Annotate="on") + + +Store in JSON message properties +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +The following sample is similar to the first one, but enables parsing of +trusted properties, which places the results into JSON/lumberjack variables. + +.. code-block:: none + :emphasize-lines: 2 + + module(load="imuxsock" + SysSock.Annotate="on" SysSock.ParseTrusted="on") + +Read log data from jails +------------------------ + +The following sample is a configuration where rsyslogd pulls logs from +two jails, and assigns different hostnames to each of the jails: + +.. code-block:: none + :emphasize-lines: 3,4,5 + + module(load="imuxsock") # needs to be done just once + input(type="imuxsock" + HostName="jail1.example.net" + Socket="/jail/1/dev/log") input(type="imuxsock" + HostName="jail2.example.net" Socket="/jail/2/dev/log") + +Read from socket on temporary file system +----------------------------------------- + +The following sample is a configuration where rsyslogd reads the openssh +log messages via a separate socket, but this socket is created on a +temporary file system. As rsyslogd starts up before the sshd daemon, it needs +to create the socket directories, because it otherwise can not open the +socket and thus not listen to openssh messages. + +.. code-block:: none + :emphasize-lines: 3,4 + + module(load="imuxsock") # needs to be done just once + input(type="imuxsock" + Socket="/var/run/sshd/dev/log" + CreatePath="on") + + +Disable rate limiting +--------------------- + +The following sample is used to turn off input rate limiting on the +system log socket. + +.. code-block:: none + :emphasize-lines: 2 + + module(load="imuxsock" # needs to be done just once + SysSock.RateLimit.Interval="0") # turn off rate limiting + diff --git a/source/configuration/modules/index.rst b/source/configuration/modules/index.rst new file mode 100644 index 0000000..be423cd --- /dev/null +++ b/source/configuration/modules/index.rst @@ -0,0 +1,33 @@ +Modules +======= + +Rsyslog has a modular design. This enables functionality to be +dynamically loaded from modules, which may also be written by any third +party. Rsyslog itself offers all non-core functionality as modules. +Consequently, there is a growing number of modules. Here is the entry +point to their documentation and what they do (list is currently not +complete) + +Please note that each module provides (case-insensitive) configuration +parameters, which are NOT necessarily being listed below. Also remember, +that a modules configuration parameter (and functionality) is only +available if it has been loaded. + +It is relatively easy to write a rsyslog module. If none of the +provided modules solve your need, you may consider writing one or have +one written for you by `Adiscon's professional services for +rsyslog <http://www.rsyslog.com/professional-services>`_ (this often +is a very cost-effective and efficient way of getting what you need). + +There exist different classes of loadable modules: + +.. toctree:: + :maxdepth: 1 + + idx_output + idx_input + idx_parser + idx_messagemod + idx_stringgen + idx_library + workflow diff --git a/source/configuration/modules/mmanon.rst b/source/configuration/modules/mmanon.rst new file mode 100644 index 0000000..b1d1a4b --- /dev/null +++ b/source/configuration/modules/mmanon.rst @@ -0,0 +1,370 @@ +**************************************** +IP Address Anonymization Module (mmanon) +**************************************** + +=========================== =========================================================================== +**Module Name:** **mmanon** +**Author:** `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com> +**Available since:** 7.3.7 +=========================== =========================================================================== + + +Purpose +======= + +The mmanon module permits to anonymize IP addresses. It is a message +modification module that actually changes the IP address inside the +message, so after calling mmanon, the original message can no longer be +obtained. Note that anonymization will break digital signatures on the +message, if they exist. + +Please note that log files can also be anonymized via +`SLFA <http://jan.gerhards.net/p/slfa.html>`_ after they +have been created. + +*How are IP-Addresses defined?* + +We assume that an IPv4 address consists of four octets in dotted notation, +where each of the octets has a value between 0 and 255, inclusively. + +An IPv6 is defined by being bewtween zero and eight hex values between 0 +and ffff. These are separated by ':'. Leading zeros in blocks can be omitted +and blocks full of zeros can be abbreviated by using '::'. However, this +can ony happen once in an IP address. + +An IPv6 address with embedded IPv4 is an IPv6 address where the last two blocks +have been replaced by an IPv4 address. (see also: RFC4291, 2.2.3) + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + + +Action Parameters +----------------- + +Parameters starting with 'IPv4.' will configure IPv4 anonymization, +while 'IPv6.' parameters do the same for IPv6 anonymization. + + +ipv4.enable +^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "none" + +Allows to enable or disable the anonymization of IPv4 addresses. + + +ipv4.mode +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "zero", "no", "none" + +There exist the "simple", "random", "random-consitent", and "zero" +modes. In simple mode, only octets as whole can be anonymized +and the length of the message is never changed. This means +that when the last three octets of the address 10.1.12.123 are +anonymized, the result will be 10.0.00.000. This means that +the length of the original octets is still visible and may be used +to draw some privacy-evasive conclusions. This mode is slightly +faster than the other modes, and this may matter in high +throughput environments. + +The modes "random" and "random-consistent" are very similar, in +that they both anonymize ip-addresses by randomizing the last bits (any +number) of a given address. However, while "random" mode assigns a new +random ip-address for every address in a message, "random-consitent" will +assign the same randomized address to every instance of the same original address. + +The default "zero" mode will do full anonymization of any number +of bits and it will also normalize the address, so that no information +about the original IP address is available. So in the above example, +10.1.12.123 would be anonymized to 10.0.0.0. + + +ipv4.bits +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "positive integer", "16", "no", "none" + +This sets the number of bits that should be anonymized (bits are from +the right, so lower bits are anonymized first). This setting permits +to save network information while still anonymizing user-specific +data. The more bits you discard, the better the anonymization +obviously is. The default of 16 bits reflects what German data +privacy rules consider as being sufficinetly anonymized. We assume, +this can also be used as a rough but conservative guideline for other +countries. +Note: when in simple mode, only bits on a byte boundary can be +specified. As such, any value other than 8, 16, 24 or 32 is invalid. +If an invalid value is given, it is rounded to the next byte boundary +(so we favor stronger anonymization in that case). For example, a bit +value of 12 will become 16 in simple mode (an error message is also +emitted). + + +ipv4.replaceChar +^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "char", "x", "no", "none" + +In simple mode, this sets the character that the to-be-anonymized +part of the IP address is to be overwritten with. In any other +mode the parameter is ignored if set. + + +ipv6.enable +^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "none" + +Allows to enable or disable the anonymization of IPv6 addresses. + + +ipv6.anonmode +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "zero", "no", "none" + +This defines the mode, in which IPv6 addresses will be anonymized. +There exist the "random", "random-consistent", and "zero" modes. + +The modes "random" and "random-consistent" are very similar, in +that they both anonymize ip-addresses by randomizing the last bits (any +number) of a given address. However, while "random" mode assigns a new +random ip-address for every address in a message, "random-consistent" will +assign the same randomized address to every instance of the same original address. + +The default "zero" mode will do full anonymization of any number +of bits and it will also normalize the address, so that no information +about the original IP address is available. + +Also note that an anonymmized IPv6 address will be normalized, meaning +there will be no abbreviations, leading zeros will **not** be displayed, +and capital letters in the hex numerals will be lowercase. + + +ipv6.bits +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "positive integer", "96", "no", "none" + +This sets the number of bits that should be anonymized (bits are from +the right, so lower bits are anonymized first). This setting permits +to save network information while still anonymizing user-specific +data. The more bits you discard, the better the anonymization +obviously is. The default of 96 bits reflects what German data +privacy rules consider as being sufficinetly anonymized. We assume, +this can also be used as a rough but conservative guideline for other +countries. + + +embeddedipv4.enable +^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "none" + +Allows to enable or disable the anonymization of IPv6 addresses with embedded IPv4. + + +embeddedipv4.anonmode +^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "zero", "no", "none" + +This defines the mode, in which IPv6 addresses will be anonymized. +There exist the "random", "random-consistent", and "zero" modes. + +The modes "random" and "random-consistent" are very similar, in +that they both anonymize ip-addresses by randomizing the last bits (any +number) of a given address. However, while "random" mode assigns a new +random ip-address for every address in a message, "random-consistent" will +assign the same randomized address to every instance of the same original address. + +The default "zero" mode will do full anonymization of any number +of bits and it will also normalize the address, so that no information +about the original IP address is available. + +Also note that an anonymmized IPv6 address will be normalized, meaning +there will be no abbreviations, leading zeros will **not** be displayed, +and capital letters in the hex numerals will be lowercase. + + +embeddedipv4.bits +^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "positive integer", "96", "no", "none" + +This sets the number of bits that should be anonymized (bits are from +the right, so lower bits are anonymized first). This setting permits +to save network information while still anonymizing user-specific +data. The more bits you discard, the better the anonymization +obviously is. The default of 96 bits reflects what German data +privacy rules consider as being sufficinetly anonymized. We assume, +this can also be used as a rough but conservative guideline for other +countries. + + +See Also +======== + +- `Howto anonymize messages that go to specific + files <http://www.rsyslog.com/howto-anonymize-messages-that-go-to-specific-files/>`_ + + +Caveats/Known Bugs +================== + +- will **not** anonymize addresses in the header + + +Examples +======== + +Anonymizing messages +-------------------- + +In this snippet, we write one file without anonymization and another one +with the message anonymized. Note that once mmanon has run, access to +the original message is no longer possible (execept if stored in user +variables before anonymization). + +.. code-block:: none + + module(load="mmanon") + action(type="omfile" file="/path/to/non-anon.log") + action(type="mmanon" ipv6.enable="off") + action(type="omfile" file="/path/to/anon.log") + + +Anonymizing a specific part of the ip address +--------------------------------------------- + +This next snippet is almost identical to the first one, but here we +anonymize the full IPv4 address. Note that by modifying the number of +bits, you can anonymize different parts of the address. Keep in mind +that in simple mode (used here), the bit values must match IP address +bytes, so for IPv4 only the values 8, 16, 24 and 32 are valid. Also, in +this example the replacement is done via asterisks instead of lower-case +"x"-letters. Also keep in mind that "replacementChar" can only be set in +simple mode. + +.. code-block:: none + + module(load="mmanon") action(type="omfile" file="/path/to/non-anon.log") + action(type="mmanon" ipv4.bits="32" ipv4.mode="simple" replacementChar="\*" ipv6.enable="off") + action(type="omfile" file="/path/to/anon.log") + + +Anonymizing an odd number of bits +--------------------------------- + +The next snippet is also based on the first one, but anonymizes an "odd" +number of bits, 12. The value of 12 is used by some folks as a +compromise between keeping privacy and still permitting to gain some more +in-depth insight from log files. Note that anonymizing 12 bits may be +insufficient to fulfill legal requirements (if such exist). + +.. code-block:: none + + module(load="mmanon") action(type="omfile" file="/path/to/non-anon.log") + action(type="mmanon" ipv4.bits="12" ipv6.enable="off") action(type="omfile" + file="/path/to/anon.log") + + +Anonymizing ipv4 and ipv6 addresses +----------------------------------- + +You can also anonymize IPv4 and IPv6 in one go using a configuration like this. + +.. code-block:: none + + module(load="mmanon") action(type="omfile" file="/path/to/non-anon.log") + action(type="mmanon" ipv4.bits="12" ipv6.bits="128" ipv6.anonmode="random") action(type="omfile" + file="/path/to/anon.log") + + +Anonymizing with default values +------------------------------- + +It is also possible to use the default configuration for both types of +anonymization. This will result in IPv4 addresses being anonymized in zero +mode anonymizing 16 bits. IPv6 addresses will also be anonymized in zero +mode anonymizing 96 bits. + +.. code-block:: none + + module(load="mmanon") + action(type="omfile" file="/path/to/non-anon.log") + action(type="mmanon") + action(type="omfile" file="/path/to/anon.log") + + +Anonymizing only ipv6 addresses +------------------------------- + +Another option is to only anonymize IPv6 addresses. When doing this you have to +disable IPv4 aonymization. This example will lead to only IPv6 addresses anonymized +(using the random-consistent mode). + +.. code-block:: none + + module(load="mmanon") + action(type="omfile" file="/path/to/non-anon.log") + action(type="mmanon" ipv4.enable="off" ipv6.anonmode="random-consistent") + action(type="omfile" file="/path/to/anon.log") + diff --git a/source/configuration/modules/mmcount.rst b/source/configuration/modules/mmcount.rst new file mode 100644 index 0000000..de3247d --- /dev/null +++ b/source/configuration/modules/mmcount.rst @@ -0,0 +1,56 @@ +******* +mmcount +******* + +=========================== =========================================================================== +**Module Name:** **mmcount** +**Author:** Bala.FA <barumuga@redhat.com> +**Available since:** 7.5.0 +=========================== =========================================================================== + + +**Status:**\ Non project-supported module - contact author or rsyslog +mailing list for questions + + +Purpose +======= + +Message modification plugin which counts messages. + +This module provides the capability to count log messages by severity +or json property of given app-name. The count value is added into the +log message as json property named 'mmcount'. + + +Examples +======== + +Example usage of the module in the configuration file. + +.. code-block:: none + + module(load="mmcount") + + # count each severity of appname gluster + action(type="mmcount" appname="gluster") + + # count each value of gf_code of appname gluster + action(type="mmcount" appname="glusterd" key="!gf_code") + + # count value 9999 of gf_code of appname gluster + action(type="mmcount" appname="glusterfsd" key="!gf_code" value="9999") + + # send email for every 50th mmcount + if $app-name == 'glusterfsd' and $!mmcount <> 0 and $!mmcount % 50 == 0 then { + $ActionMailSMTPServer smtp.example.com + $ActionMailFrom rsyslog@example.com + $ActionMailTo glusteradmin@example.com + $template mailSubject,"50th message of gf_code=9999 on %hostname%" + $template mailBody,"RSYSLOG Alert\r\nmsg='%msg%'" + $ActionMailSubject mailSubject + $ActionExecOnlyOnceEveryInterval 30 + :ommail:;RSYSLOG_SyslogProtocol23Format + } + + diff --git a/source/configuration/modules/mmdarwin.rst b/source/configuration/modules/mmdarwin.rst new file mode 100644 index 0000000..17d8c0d --- /dev/null +++ b/source/configuration/modules/mmdarwin.rst @@ -0,0 +1,229 @@ +.. index:: ! mmdarwin + +.. role:: json(code) + :language: json + +*************************** +Darwin connector (mmdarwin) +*************************** + +================ =========================================== +**Module Name:** **mmdarwin** +**Author:** Guillaume Catto <guillaume.catto@advens.fr>, + Theo Bertin <theo.bertin@advens.fr> +================ =========================================== + +Purpose +======= + +Darwin is an open source Artificial Intelligence Framework for CyberSecurity. The mmdarwin module allows us to call Darwin in order to enrich our JSON-parsed logs with a score, and/or to allow Darwin to generate alerts. + +How to build the module +======================= + +To compile Rsyslog with mmdarwin you'll need to: + +* set *--enable-mmdarwin* on configure + +Configuration Parameter +======================= + +Input Parameters +---------------- + +key +^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "yes", "none" + +The key name to use to store the returned data. + +For example, given the following log line: + +.. code-block:: json + + { + "from": "192.168.1.42", + "date": "2012-12-21 00:00:00", + "status": "200", + "data": { + "status": true, + "message": "Request processed correctly" + } + } + +and the :json:`"certitude"` key, the enriched log line would be: + +.. code-block:: json + :emphasize-lines: 9 + + { + "from": "192.168.1.42", + "date": "2012-12-21 00:00:00", + "status": "200", + "data": { + "status": true, + "message": "Request processed correctly" + }, + "certitude": 0 + } + +where :json:`"certitude"` represents the score returned by Darwin. + + +socketpath +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "yes", "none" + +The Darwin filter socket path to use. + + +response +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", \"no", "no", "none" + +Tells the Darwin filter what to do next: + +* :json:`"no"`: no response will be sent, nothing will be sent to next filter. +* :json:`"back"`: a score for the input will be returned by the filter, nothing will be forwarded to the next filter. +* :json:`"darwin"`: the data provided will be forwarded to the next filter (in the format specified in the filter's configuration), no response will be given to mmdarwin. +* :json:`"both"`: the filter will respond to mmdarwin with the input's score AND forward the data (in the format specified in the filter's configuration) to the next filter. + +.. note:: + + Please be mindful when setting this parameter, as the called filter will only forward data to the next configured filter if you ask the filter to do so with :json:`"darwin"` or :json:`"both"`, if a next filter if configured but you ask for a :json:`"back"` response, the next filter **WILL NOT** receive anything! + +filtercode +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "0x00000000", "no", "none" + +Each Darwin module has a unique filter code. For example, the code of the hostlookup filter is :json:`"0x66726570"`. +This code was mandatory but has now become obsolete. you can leave it as it is. + +fields +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "array", "none", "yes", "none" + +Array containing values to be sent to Darwin as parameters. + +Two types of values can be set: + +* if it starts with a bang (:json:`"!"`), mmdarwin will search in the JSON-parsed log line the associated value. You can search in subkeys as well: just add a bang to go to a deeper level. +* otherwise, the value is considered static, and will be forwarded directly to Darwin. + +For example, given the following log line: + +.. code-block:: json + + { + "from": "192.168.1.42", + "date": "2012-12-21 00:00:00", + "status": "200", + "data": { + "status": true, + "message": "Request processed correctly" + } + } + +and the :json:`"fields"` array: + +.. code-block:: none + + ["!from", "!data!status", "rsyslog"] + +The parameters sent to Darwin would be :json:`"192.168.1.42"`, :json:`true` and :json:`"rsyslog"`. + +.. note:: + The order of the parameters is important. Thus, you have to be careful when providing the fields in the array. + Refer to `Darwin documentation`_ to see what each filter requires as parameters. + +.. _`Darwin documentation`: https://github.com/VultureProject/darwin/wiki + +send_partial +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "boolean", "off", "no", "none" + +Whether to send to Darwin if not all :json:`"fields"` could be found in the message, or not. +All current Darwin filters required a strict number (and format) of parameters as input, so they will most likely not process the data if some fields are missing. This should be kept to "off", unless you know what you're doing. + +For example, for the following log line: + +.. code-block:: json + + { + "from": "192.168.1.42", + "date": "2012-12-21 00:00:00", + "status": "200", + "data": { + "status": true, + "message": "Request processed correctly" + } + } + +and the :json:`"fields"` array: + +.. code-block:: none + + ["!from", "!data!status", "!this!field!is!not!in!message"] + +the third field won't be found, so the call to Darwin will be dropped. + + +Configuration example +===================== + +This example shows a possible configuration of mmdarwin. + +.. code-block:: none + + module(load="imtcp") + module(load="mmjsonparse") + module(load="mmdarwin") + + input(type="imtcp" port="8042" Ruleset="darwin_ruleset") + + ruleset(name="darwin_ruleset") { + action(type="mmjsonparse" cookie="") + action(type="mmdarwin" socketpath="/path/to/reputation_1.sock" fields=["!srcip", "ATTACK;TOR"] key="reputation" response="back" filtercode="0x72657075") + + call darwin_output + } + + ruleset(name="darwin_output") { + action(type="omfile" file="/path/to/darwin_output.log") + } diff --git a/source/configuration/modules/mmdblookup.rst b/source/configuration/modules/mmdblookup.rst new file mode 100644 index 0000000..d92f849 --- /dev/null +++ b/source/configuration/modules/mmdblookup.rst @@ -0,0 +1,141 @@ +.. index:: ! mmdblookup + +************************************ +MaxMind/GeoIP DB lookup (mmdblookup) +************************************ + +================ ================================== +**Module Name:** mmdblookup +**Author:** `chenryn <rao.chenlin@gmail.com>`_ +**Available:** 8.24+ +================ ================================== + + +Purpose +======= + +MaxMindDB is the new file format for storing information about IP addresses +in a highly optimized, flexible database format. GeoIP2 Databases are +available in the MaxMind DB format. + +Plugin author claimed a MaxMindDB vs GeoIP speed around 4 to 6 times. + + +How to build the module +======================= + +To compile Rsyslog with mmdblookup you'll need to: + +* install *libmaxminddb-devel* package +* set *--enable-mmdblookup* on configure + + +Configuration Parameter +======================= + +.. note:: + + Parameter names are case-insensitive. + + +Module Parameters +----------------- + +container +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "!iplocation", "no", "none" + +.. versionadded:: 8.28.0 + +Specifies the container to be used to store the fields amended by +mmdblookup. + + +Input Parameters +---------------- + +key +^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "yes", "none" + +Name of field containing IP address. + + +mmdbfile +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "yes", "none" + +Location of Maxmind DB file. + + +fields +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "array", "none", "yes", "none" + +Fields that will be appended to processed message. The fields will +always be appended in the container used by mmdblookup (which may be +overridden by the "container" parameter on module load). + +By default, the maxmindb field name is used for variables. This can +be overridden by specifying a custom name between colons at the +beginning of the field name. As usual, bang signs denote path levels. +So for example, if you want to extract "!city!names!en" but rename it +to "cityname", you can use ":cityname:!city!names!en" as field name. + + +Examples +======== + +Minimum configuration +--------------------- + +This example shows the minimum configuration. + +.. code-block:: none + + # load module + module( load="mmdblookup" ) + + action( type="mmdblookup" mmdbfile="/etc/rsyslog.d/GeoLite2-City.mmdb" + fields=["!continent!code","!location"] key="!clientip" ) + + +Custom container and field name +------------------------------- + +The following example uses a custom container and custom field name + +.. code-block:: none + + # load module + module( load="mmdblookup" container="!geo_ip") + + action( type="mmdblookup" mmdbfile="/etc/rsyslog.d/GeoLite2-City.mmdb" + fields=[":continent:!continent!code", ":loc:!location"] + key="!clientip") + + diff --git a/source/configuration/modules/mmexternal.rst b/source/configuration/modules/mmexternal.rst new file mode 100644 index 0000000..afc85cc --- /dev/null +++ b/source/configuration/modules/mmexternal.rst @@ -0,0 +1,110 @@ +******************************************************** +Support module for external message modification modules +******************************************************** + +=========================== =========================================================================== +**Module Name:** **mmexternal** +**Author:** `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com> +**Available since:** 8.3.0 +=========================== =========================================================================== + + +Purpose +======= + +This module permits to integrate external message modification plugins +into rsyslog. + +For details on the interface specification, see rsyslog's source in the +./plugins/external/INTERFACE.md. + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + + +Action Parameters +----------------- + +binary +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "yes", "none" + +The name of the external message modification plugin to be called. This +can be a full path name. + + +interface.input +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "msg", "no", "none" + +This can either be "msg", "rawmsg" or "fulljson". In case of "fulljson", the +message object is provided as a json object. Otherwise, the respective +property is provided. This setting **must** match the external plugin's +expectations. Check the external plugin documentation for what needs to be used. + + +output +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +This is a debug aid. If set, this is a filename where the plugins output +is logged. Note that the output is also being processed as usual by rsyslog. +Setting this parameter thus gives insight into the internal processing +that happens between plugin and rsyslog core. + + +forceSingleInstance +^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +This is an expert parameter, just like the equivalent *omprog* parameter. +See the message modification plugin's documentation if it is needed. + + +Examples +======== + +Execute external module +----------------------- + +The following config file snippet is used to write execute an external +message modification module "mmexternal.py". Note that the path to the +module is specified here. This is necessary if the module is not in the +default search path. + +.. code-block:: none + + module (load="mmexternal") # needs to be done only once inside the config + + action(type="mmexternal" binary="/path/to/mmexternal.py") + + diff --git a/source/configuration/modules/mmfields.rst b/source/configuration/modules/mmfields.rst new file mode 100644 index 0000000..876a7ca --- /dev/null +++ b/source/configuration/modules/mmfields.rst @@ -0,0 +1,132 @@ +*********************************** +Fields Extraction Module (mmfields) +*********************************** + +=========================== =========================================================================== +**Module Name:** **mmfields** +**Author:** `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com> +**Available since:** 7.5.1 +=========================== =========================================================================== + + +Purpose +======= + +The mmfield module permits to extract fields. It is an alternate to +using the property replacer field extraction capabilities. In contrast +to the property replacer, all fields are extracted as once and stored +inside the structured data part (more precisely: they become Lumberjack +[JSON] properties). + +Using this module is of special advantage if a field-based log format is +to be processed, like for example CEF **and** either a large number +of fields is needed or a specific field is used multiple times inside +filters. In these scenarios, mmfields potentially offers better +performance than the property replacer of the RainerScript field +extraction method. The reason is that mmfields extracts all fields as +one big sweep, whereas the other methods extract fields individually, +which requires multiple passes through the same data. On the other hand, +adding field content to the rsyslog property dictionary also has some +overhead, so for high-performance use cases it is suggested to do some +performance testing before finally deciding which method to use. This is +most important if only a smaller subset of the fields is actually +needed. + +In any case, mmfields provides a very handy and easy to use way to parse +structured data into a it's individual data items. Again, a primary use +case was support for CEF (Common Event Format), which is made extremely +easy to do with this module. + +This module is implemented via the action interface. Thus it can be +conditionally used depending on some prerequisites. + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + + +Action Parameters +----------------- + +separator +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "char", ",", "no", "none" + +This is the character used to separate fields. Currently, only a +single character is permitted, while the RainerScript method permits +to specify multi-character separator strings. For CEF, this is not +required. If there is actual need to support multi-character +separator strings, support can relatively easy be added. It is +suggested to request it on the rsyslog mailing list, together with +the use case - we intend to add functionality only if there is a real +use case behind the request (in the past we too-often implemented +things that actually never got used). +The fields are named f\ *nbr*, where *nbr* is the field number +starting with one and being incremented for each field. + + +jsonRoot +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "!", "no", "none" + +This parameters specifies into which json path the extracted fields +shall be written. The default is to use the json root object itself. + + +Examples +======== + +Parsing messages and writing them to file +----------------------------------------- + +This is a very simple use case where each message is parsed. The default +separator character of comma is being used. + +.. code-block:: none + + module(load="mmfields") + template(name="ftpl" + type="string" + string="%$!%\\n") + action(type="mmfields") + action(type="omfile" + file="/path/to/logfile" + template="ftpl") + + +Writing into a specific json path +--------------------------------- + +The following sample is similar to the previous one, but this time the +colon is used as separator and data is written into the "$!mmfields" +json path. + +.. code-block:: none + + module(load="mmfields") + template(name="ftpl" + type="string" + string="%$!%\\n") + action(type="mmfields" + separator=":" + jsonRoot="!mmfields") + action(type="omfile" + file="/path/to/logfile" + template="ftpl") + diff --git a/source/configuration/modules/mmjsonparse.rst b/source/configuration/modules/mmjsonparse.rst new file mode 100644 index 0000000..3d47c4f --- /dev/null +++ b/source/configuration/modules/mmjsonparse.rst @@ -0,0 +1,147 @@ +*********************************************************** +JSON/CEE Structured Content Extraction Module (mmjsonparse) +*********************************************************** + +=========================== =========================================================================== +**Module Name:** **mmjsonparse** +**Author:** `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com> +**Available since:** 6.6.0 +=========================== =========================================================================== + + +Purpose +======= + +This module provides support for parsing structured log messages that +follow the CEE/lumberjack spec. The so-called "CEE cookie" is checked +and, if present, the JSON-encoded structured message content is parsed. +The properties are then available as original message properties. + +As a convenience, mmjsonparse will produce a valid CEE/lumberjack log +message if passed a message without the CEE cookie. A JSON structure +will be created and the "msg" field will be the only field and it will +contain the message. Note that in this case, mmjsonparse will +nonetheless return that the JSON parsing has failed. + +The "CEE cookie" is the character squence "@cee:" which must prepend the +actual JSON. Note that the JSON must be valid and MUST NOT be followed +by any non-JSON message. If either of these conditions is not true, +mmjsonparse will **not** parse the associated JSON. This is based on the +cookie definition used in CEE/project lumberjack and is meant to aid +against an erroneous detection of a message as being CEE where it is +not. + +This also means that mmjsonparse currently is NOT a generic JSON parser +that picks up JSON from wherever it may occur in the message. This is +intentional, but future versions may support config parameters to relax +the format requirements. + + +Notable Features +================ + +- :ref:`mmjsonparse-parsing-result` + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + + +Action Parameters +----------------- + +cookie +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "@cee:", "no", "none" + +Permits to set the cookie that must be present in front of the +JSON part of the message. + +Most importantly, this can be set to the empty string ("") in order +to not require any cookie. In this case, leading spaces are permitted +in front of the JSON. No non-whitespace characters are permitted +after the JSON. If such is required, mmnormalize must be used. + + +useRawMsg +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +Specifies if the raw message should be used for normalization (on) +or just the MSG part of the message (off). + + +container +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "$!", "no", "none" + +Specifies the JSON container (path) under which parsed elements should be +placed. By default, all parsed properties are merged into root of +message properties. You can place them under a subtree, instead. You +can place them in local variables, also, by setting path="$.". + + +.. _mmjsonparse-parsing-result: + +Check parsing result +==================== + +You can check whether rsyslogd was able to successfully parse the +message by reading the $parsesuccess variable : + +.. code-block:: none + + action(type="mmjsonparse") + if $parsesuccess == "OK" then { + action(type="omfile" File="/tmp/output") + } + else if $parsesuccess == "FAIL" then { + action(type="omfile" File="/tmp/parsing_failure") + } + + +Examples +======== + +Apply default normalization +--------------------------- + +This activates the module and applies normalization to all messages. + +.. code-block:: none + + module(load="mmjsonparse") + action(type="mmjsonparse") + + +Permit parsing messages without cookie +-------------------------------------- + +To permit parsing messages without cookie, use this action statement + +.. code-block:: none + + action(type="mmjsonparse" cookie="") + diff --git a/source/configuration/modules/mmkubernetes.rst b/source/configuration/modules/mmkubernetes.rst new file mode 100644 index 0000000..83efc18 --- /dev/null +++ b/source/configuration/modules/mmkubernetes.rst @@ -0,0 +1,630 @@ +***************************************** +Kubernetes Metadata Module (mmkubernetes) +***************************************** + +=========================== =========================================================================== +**Module Name:** **mmkubernetes** +**Author:** `Tomáš Heinrich` + `Rich Megginson` <rmeggins@redhat.com> +=========================== =========================================================================== + +Purpose +======= + +This module is used to add `Kubernetes <https://kubernetes.io/>` +metadata to log messages logged by containers running in Kubernetes. +It will add the namespace uuid, pod uuid, pod and namespace labels and +annotations, and other metadata associated with the pod and +namespace. + +.. note:: + + This **only** works with log files in `/var/log/containers/*.log` (docker + `--log-driver=json-file`, or CRI-O log files), or with journald entries with + message properties `CONTAINER_NAME` and `CONTAINER_ID_FULL` (docker + `--log-driver=journald`), and when the application running inside the + container writes logs to `stdout`/`stderr`. This **does not** currently + work with other log drivers. + +For json-file and CRI-O logs, you must use the `imfile` module with the +`addmetadata="on"` parameter, and the filename must match the +liblognorm rules specified by the `filenamerules` +(:ref:`filenamerules`) or `filenamerulebase` (:ref:`filenamerulebase`) +parameter values. + +For journald logs, there must be a message property `CONTAINER_NAME` +which matches the liblognorm rules specified by the `containerrules` +(:ref:`containerrules`) or `containerrulebase` +(:ref:`containerrulebase`) parameter values. The record must also have +the message property `CONTAINER_ID_FULL`. + +This module is implemented via the output module interface. This means +that mmkubernetes should be called just like an action. After it has +been called, there will be two new message properties: `kubernetes` +and `docker`. There will be subfields of each one for the various +metadata items: `$!kubernetes!namespace_name` +`$!kubernetes!labels!this-is-my-label`, etc. There is currently only +1 docker subfield: `$!docker!container_id`. See +https://github.com/ViaQ/elasticsearch-templates/blob/master/namespaces/kubernetes.yml +and +https://github.com/ViaQ/elasticsearch-templates/blob/master/namespaces/docker.yml +for more details. + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + +Module Parameters and Action Parameters +--------------------------------------- + +.. _kubernetesurl: + +KubernetesURL +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "https://kubernetes.default.svc.cluster.local:443", "no", "none" + +The URL of the Kubernetes API server. Example: `https://localhost:8443`. + +.. _mmkubernetes-tls.cacert: + +tls.cacert +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +Full path and file name of file containing the CA cert of the +Kubernetes API server cert issuer. Example: `/etc/rsyslog.d/mmk8s-ca.crt`. +This parameter is not mandatory if using an `http` scheme instead of `https` in +`kubernetesurl`, or if using `allowunsignedcerts="yes"`. + +.. _mmkubernetes-tls.mycert: + +tls.mycert +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +This is the full path and file name of the file containing the client cert for +doing client cert auth against Kubernetes. This file is in PEM format. For +example: `/etc/rsyslog.d/k8s-client-cert.pem` + +.. _mmkubernetes-tls.myprivkey: + +tls.myprivkey +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +This is the full path and file name of the file containing the private key +corresponding to the cert `tls.mycert` used for doing client cert auth against +Kubernetes. This file is in PEM format, and must be unencrypted, so take +care to secure it properly. For example: `/etc/rsyslog.d/k8s-client-key.pem` + +.. _tokenfile: + +tokenfile +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +The file containing the token to use to authenticate to the Kubernetes API +server. One of `tokenfile` or `token` is required if Kubernetes is configured +with access control. Example: `/etc/rsyslog.d/mmk8s.token` + +.. _token: + +token +^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +The token to use to authenticate to the Kubernetes API server. One of `token` +or `tokenfile` is required if Kubernetes is configured with access control. +Example: `UxMU46ptoEWOSqLNa1bFmH` + +.. _annotation_match: + +annotation_match +^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "array", "none", "no", "none" + +By default no pod or namespace annotations will be added to the +messages. This parameter is an array of patterns to match the keys of +the `annotations` field in the pod and namespace metadata to include +in the `$!kubernetes!annotations` (for pod annotations) or the +`$!kubernetes!namespace_annotations` (for namespace annotations) +message properties. Example: `["k8s.*master","k8s.*node"]` + +.. _srcmetadatapath: + +srcmetadatapath +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "$!metadata!filename", "no", "none" + +When reading json-file logs, with `imfile` and `addmetadata="on"`, +this is the property where the filename is stored. + +.. _dstmetadatapath: + +dstmetadatapath +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "$!", "no", "none" + +This is the where the `kubernetes` and `docker` properties will be +written. By default, the module will add `$!kubernetes` and +`$!docker`. + +.. _allowunsignedcerts: + +allowunsignedcerts +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "boolean", "off", "no", "none" + +If `"on"`, this will set the curl `CURLOPT_SSL_VERIFYPEER` option to +`0`. You are strongly discouraged to set this to `"on"`. It is +primarily useful only for debugging or testing. + +.. _skipverifyhost: + +skipverifyhost +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "boolean", "off", "no", "none" + +If `"on"`, this will set the curl `CURLOPT_SSL_VERIFYHOST` option to +`0`. You are strongly discouraged to set this to `"on"`. It is +primarily useful only for debugging or testing. + +.. _de_dot: + +de_dot +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "boolean", "on", "no", "none" + +When processing labels and annotations, if this parameter is set to +`"on"`, the key strings will have their `.` characters replaced with +the string specified by the `de_dot_separator` parameter. + +.. _de_dot_separator: + +de_dot_separator +^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "_", "no", "none" + +When processing labels and annotations, if the `de_dot` parameter is +set to `"on"`, the key strings will have their `.` characters replaced +with the string specified by the string value of this parameter. + +.. _filenamerules: + +filenamerules +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "SEE BELOW", "no", "none" + +.. note:: + + This directive is not supported with liblognorm 2.0.2 and earlier. + +When processing json-file logs, these are the lognorm rules to use to +match the filename and extract metadata. The default value is:: + + rule=:/var/log/containers/%pod_name:char-to:_%_%namespace_name:char-to:_%_%contai\ + ner_name_and_id:char-to:.%.log + +.. note:: + + In the above rules, the slashes ``\`` ending each line indicate + line wrapping - they are not part of the rule. + +.. _filenamerulebase: + +filenamerulebase +^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "/etc/rsyslog.d/k8s_filename.rulebase", "no", "none" + +When processing json-file logs, this is the rulebase used to match the filename +and extract metadata. For the actual rules, see :ref:`filenamerules`. + +.. _containerrules: + +containerrules +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "SEE BELOW", "no", "none" + +.. note:: + + This directive is not supported with liblognorm 2.0.2 and earlier. + +For journald logs, there must be a message property `CONTAINER_NAME` +which has a value matching these rules specified by this parameter. +The default value is:: + + rule=:%k8s_prefix:char-to:_%_%container_name:char-to:.%.%container_hash:char-to:\ + _%_%pod_name:char-to:_%_%namespace_name:char-to:_%_%not_used_1:char-to:_%_%not_u\ + sed_2:rest% + rule=:%k8s_prefix:char-to:_%_%container_name:char-to:_%_%pod_name:char-to:_%_%na\ + mespace_name:char-to:_%_%not_used_1:char-to:_%_%not_used_2:rest% + +.. note:: + + In the above rules, the slashes ``\`` ending each line indicate + line wrapping - they are not part of the rule. + +There are two rules because the `container_hash` is optional. + +.. _containerrulebase: + +containerrulebase +^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "/etc/rsyslog.d/k8s_container_name.rulebase", "no", "none" + +When processing json-file logs, this is the rulebase used to match the +CONTAINER_NAME property value and extract metadata. For the actual rules, see +:ref:`containerrules`. + +.. _mmkubernetes-busyretryinterval: + +busyretryinterval +^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "5", "no", "none" + +The number of seconds to wait before retrying operations to the Kubernetes API +server after receiving a `429 Busy` response. The default `"5"` means that the +module will retry the connection every `5` seconds. Records processed during +this time will _not_ have any additional metadata associated with them, so you +will need to handle cases where some of your records have all of the metadata +and some do not. + +If you want to have rsyslog suspend the plugin until the Kubernetes API server +is available, set `busyretryinterval` to `"0"`. This will cause the plugin to +return an error to rsyslog. + +.. _mmkubernetes-sslpartialchain: + +sslpartialchain +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "boolean", "off", "no", "none" + +This option is only available if rsyslog was built with support for OpenSSL and +only if the `X509_V_FLAG_PARTIAL_CHAIN` flag is available. If you attempt to +set this parameter on other platforms, you will get an `INFO` level log +message. This was done so that you could use the same configuration on +different platforms. +If `"on"`, this will set the OpenSSL certificate store flag +`X509_V_FLAG_PARTIAL_CHAIN`. This will allow you to verify the Kubernetes API +server cert with only an intermediate CA cert in your local trust store, rather +than having to have the entire intermediate CA + root CA chain in your local +trust store. See also `man s_client` - the `-partial_chain` flag. +If you get errors like this, you probably need to set `sslpartialchain="on"`: + +.. code-block:: none + + rsyslogd: mmkubernetes: failed to connect to [https://...url...] - + 60:Peer certificate cannot be authenticated with given CA certificates + +.. _mmkubernetes-cacheexpireinterval: + +cacheexpireinterval +^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "-1", "no", "none" + +This parameter allows you to expire entries from the metadata cache. The +values are: + +- -1 (default) - disables metadata cache expiration +- 0 - check cache for expired entries before every cache lookup +- 1 or higher - the number is a number of seconds - check the cache + for expired entries every this many seconds, when processing an + entry + +The cache is only checked if processing a record from Kubernetes. There +isn't some sort of housekeeping thread that continually runs cleaning up +the cache. When an record from Kubernetes is processed: + +If `cacheexpireinterval` is -1, then do not check for cache expiration. +If `cacheexpireinterval` is 0, then check for cache expiration. +If `cacheexpireinterval` is greater than 0, check for cache expiration +if the last time we checked was more than this many seconds ago. + +When cache expiration is checked, it will delete all cache entries which +have a ttl less than or equal to the current time. The cache entry ttl +is set using the `cacheentryttl`. + +.. _mmkubernetes-cacheentryttl: + +cacheentryttl +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "3600", "no", "none" + +This parameter allows you to set the maximum age (time-to-live, or ttl) of +an entry in the metadata cache. The value is in seconds. The default value +is `3600` (one hour). When cache expiration is checked, if a cache entry +has a ttl less than or equal to the current time, it will be removed from +the cache. + +This option is only used if `cacheexpireinterval` is 0 or greater. + +This value must be 0 or greater, otherwise, if `cacheexpireinterval` is 0 +or greater, you will get an error. + +.. _mmkubernetes-statistic-counter: + +Statistic Counter +================= + +This plugin maintains per-action :doc:`statistics +<../rsyslog_statistic_counter>`. The statistic is named +"mmkubernetes($kubernetesurl)", where `$kubernetesurl` is the +:ref:`kubernetesurl` setting for the action. + +Parameters are: + +- **recordseen** - number of messages seen by the action which the action has + determined have Kubernetes metadata associated with them + +- **namespacemetadatasuccess** - the number of times a successful request was + made to the Kubernetes API server for namespace metadata. + +- **namespacemetadatanotfound** - the number of times a request to the + Kubernetes API server for namespace metadata was returned with a `404 Not + Found` error code - the namespace did not exist at that time. + +- **namespacemetadatabusy** - the number of times a request to the Kubernetes + API server for namespace metadata was returned with a `429 Busy` error + code - the server was too busy to send a proper response. + +- **namespacemetadataerror** - the number of times a request to the Kubernetes + API server for namespace metadata was returned with some other error code + not handled above. These are typically "hard" errors which require some + sort of intervention to fix e.g. Kubernetes server down, credentials incorrect. + +- **podmetadatasuccess** - the number of times a successful request was made + to the Kubernetes API server for pod metadata. + +- **podmetadatanotfound** - the number of times a request to the Kubernetes + API server for pod metadata was returned with a `404 Not Found` error code - + the pod did not exist at that time. + +- **podmetadatabusy** - the number of times a request to the Kubernetes API + server for pod metadata was returned with a `429 Busy` error code - the + server was too busy to send a proper response. + +- **podmetadataerror** - the number of times a request to the Kubernetes API + server for pod metadata was returned with some other error code not handled + above. These are typically "hard" errors which require some sort of + intervention to fix e.g. Kubernetes server down, credentials incorrect. + +- **podcachenumentries** - the number of entries in the pod metadata cache. + +- **namespacecachenumentries** - the number of entries in the namespace metadata + cache. + +- **podcachehits** - the number of times a requested entry was found in the + pod metadata cache. + +- **namespacecachehits** - the number of times a requested entry was found in the + namespace metadata cache. + +- **podcachemisses** - the number of times a requested entry was not found in the + pod metadata cache, and had to be requested from Kubernetes. + +- **namespacecachemisses** - the number of times a requested entry was not found + in the namespace metadata cache, and had to be requested from Kubernetes. + +Fields +------ + +These are the fields added from the metadata in the json-file filename, or from +the `CONTAINER_NAME` and `CONTAINER_ID_FULL` fields from the `imjournal` input: + +`$!kubernetes!namespace_name`, `$!kubernetes!pod_name`, +`$!kubernetes!container_name`, `$!docker!id`, `$!kubernetes!master_url`. + +If mmkubernetes can extract the above fields from the input, the following +fields will always be present. If they are not present, mmkubernetes +failed to look up the namespace or pod in Kubernetes: + +`$!kubernetes!namespace_id`, `$!kubernetes!pod_id`, +`$!kubernetes!creation_timestamp`, `$!kubernetes!host` + +The following fields may be present, depending on how the namespace and pod are +defined in Kubernetes, and depending on the value of the directive +`annotation_match`: + +`$!kubernetes!labels`, `$!kubernetes!annotations`, `$!kubernetes!namespace_labels`, +`$!kubernetes!namespace_annotations` + +More fields may be added in the future. + +Error Handling +-------------- +If the plugin encounters a `404 Not Found` in response to a request for +namespace or pod metadata, that is, the pod or namespace is missing, the plugin +will cache that result, and no metadata will be available for that pod or +namespace forever. If the pod or namespace is recreated, you will need to +restart rsyslog in order to clear the cache and allow it to find that metadata. + +If the plugin gets a `429 Busy` response, the plugin will _not_ cache that +result, and will _not_ add the metadata to the record. This can happen in very +large Kubernetes clusters when you run into the upper limit on the number of +concurrent Kubernetes API service connections. You may have to increase that +limit. In the meantime, you can control what the plugin does with those +records using the :ref:`mmkubernetes-busyretryinterval` setting. If you want +to continue to process the records, but with incomplete metadata, set +`busyretryinterval` to a non-zero value, which will be the number of seconds +after which mmkubernetes will retry the connection. The default value is `5`, +so by default, the plugin will retry the connection every `5` seconds. If the +`429` error condition in the Kubernetes API server is brief and transient, this +means you will have some (hopefully small) number of records without the +metadata such as the uuids, labels, and annotations, but your pipeline will not +stop. If the `429` error condition in the Kubernetes API server is persistent, +it may require Kubernetes API server administrator intervention to address, and +you may want to use the `busyretryinterval` value of `"0"`. This will cause +the module to return a "hard" error (see below). + +For other errors, the plugin will assume they are "hard" errors requiring admin +intervention, return an error code, and rsyslog will suspend the plugin. Use +the :ref:`mmkubernetes-statistic-counter` to monitor for problems getting data +from the Kubernetes API service. + +Example +------- + +Assuming you have an `imfile` input reading from docker json-file container +logs managed by Kubernetes, with `addmetadata="on"` so that mmkubernetes can +get the basic necessary Kubernetes metadata from the filename: + +.. code-block:: none + + input(type="imfile" file="/var/log/containers/*.log" + tag="kubernetes" addmetadata="on") + +(Add `reopenOnTruncate="on"` if using Docker, not required by CRI-O). + +and/or an `imjournal` input for docker journald container logs annotated by +Kubernetes: + +.. code-block:: none + + input(type="imjournal") + +Then mmkubernetes can be used to annotate log records like this: + +.. code-block:: none + + module(load="mmkubernetes") + + action(type="mmkubernetes") + +After this, you should have log records with fields described in the `Fields` +section above. + +Credits +------- + +This work is based on +https://github.com/fabric8io/fluent-plugin-kubernetes_metadata_filter +and has many of the same features. diff --git a/source/configuration/modules/mmnormalize.rst b/source/configuration/modules/mmnormalize.rst new file mode 100644 index 0000000..7d526a5 --- /dev/null +++ b/source/configuration/modules/mmnormalize.rst @@ -0,0 +1,178 @@ +Log Message Normalization Module (mmnormalize) +============================================== + +**Module Name: mmnormalize** + +**Available since:** 6.1.2+ + +**Author:** Rainer Gerhards <rgerhards@adiscon.com> + +**Description**: + +This module provides the capability to normalize log messages via +`liblognorm <http://www.liblognorm.com>`_. Thanks to liblognorm, +unstructured text, like usually found in log messages, can very quickly +be parsed and put into a normal form. This is done so quickly, that it +should be possible to normalize events in realtime. + +This module is implemented via the output module interface. This means +that mmnormalize should be called just like an action. After it has been +called, the normalized message properties are available and can be +accessed. These properties are called the "CEE/lumberjack" properties, +because liblognorm creates a format that is inspired by the +CEE/lumberjack approach. + +**Please note:** CEE/lumberjack properties are different from regular +properties. They have always "$!" prepended to the property name given +in the rulebase. Such a property needs to be called with +**%$!propertyname%**. + +Note that from a performance point of view mmnormalize should only be called +once on each message, if possible. To do so, place all rules into a single +rule base. If that is not possible, you can safely call mmnormalize multiple +times. This incurs a small performance drawback. + +Module Parameters +~~~~~~~~~~~~~~~~~ + +Note: parameter names are case-insensitive. + +.. function:: allow_regex <boolean> + + **Default**: off + + Specifies if regex field-type should be allowed. Regex field-type has + significantly higher computational overhead compared to other fields, + so it should be avoided when another field-type can achieve the desired + effect. Needs to be "on" for regex field-type to work. + +Action Parameters +~~~~~~~~~~~~~~~~~ + +Note: parameter names are case-insensitive. + +.. function:: ruleBase <word> + + Specifies which rulebase file is to use. If there are multiple + mmnormalize instances, each one can use a different file. However, a + single instance can use only a single file. This parameter or **rule** MUST be + given, because normalization can only happen based on a rulebase. It + is recommended that an absolute path name is given. Information on + how to create the rulebase can be found in the `liblognorm + manual <http://www.liblognorm.com/files/manual/index.html>`_. + +.. function:: rule <array> + + *(Available since: 8.26.0)* + + Contains an array of strings which will be put together as the rulebase. This parameter + or **rulebase** MUST be given, because normalization can only happen based on a rulebase. + +.. function:: useRawMsg <boolean> + + **Default**: off + + Specifies if the raw message should be used for normalization (on) + or just the MSG part of the message (off). + +.. function:: path <word> + + **Default**: $! + + Specifies the JSON path under which parsed elements should be + placed. By default, all parsed properties are merged into root of + message properties. You can place them under a subtree, instead. You + can place them in local variables, also, by setting path="$.". + +.. function:: variable <word> + + *(Available since: 8.5.1)* + + Specifies if a variable insteed of property 'msg' should be used for + normalization. A variable can be property, local variable, json-path etc. + Please note that **useRawMsg** overrides this parameter, so if **useRawMsg** + is set, **variable** will be ignored and raw message will be used. + + + + +Legacy Configuration Parameters +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +Note: parameter names are case-insensitive. + +- $mmnormalizeRuleBase <rulebase-file> - equivalent to the "ruleBase" + parameter. +- $mmnormalizeUseRawMsg <on/off> - equivalent to the "useRawMsg" + parameter. + +See Also +~~~~~~~~ + +- `First steps for + mmnormalize <http://www.rsyslog.com/normalizer-first-steps-for-mmnormalize/>`_ +- `Log normalization and special + characters <http://www.rsyslog.com/log-normalization-and-special-characters/>`_ +- `Log normalization and the leading + space <http://www.rsyslog.com/log-normalization-and-the-leading-space/>`_ +- `Using mmnormalize effectively with Adiscon + LogAnalyzer <http://www.rsyslog.com/using-rsyslog-mmnormalize-module-effectively-with-adiscon-loganalyzer/>`_ + +Caveats/Known Bugs +~~~~~~~~~~~~~~~~~~ + +None known at this time. + +Example +~~~~~~~ + +**Sample 1:** + +In this sample messages are received via imtcp. Then they are normalized with the given rulebase. +After that they are written in a file. + +:: + + module(load="mmnormalize") + module(load="imtcp") + + input(type="imtcp" port="10514" ruleset="outp") + + ruleset(name="outp") { + action(type="mmnormalize" rulebase="/tmp/rules.rulebase") + action(type="omfile" File="/tmp/output") + } + +**Sample 2:** + +In this sample messages are received via imtcp. Then they are normalized based on the given rules. +The strings from **rule** are put together and are equal to a rulebase with the same content. + +:: + + module(load="mmnormalize") + module(load="imtcp") + + input(type="imtcp" port="10514" ruleset="outp") + + ruleset(name="outp") { + action(type="mmnormalize" rule=["rule=:%host:word% %tag:char-to:\\x3a%: no longer listening on %ip:ipv4%#%port:number%", "rule=:%host:word% %ip:ipv4% user was logged out"]) + action(type="omfile" File="/tmp/output") + } + +**Sample 3:** + +This activates the module and applies normalization to all messages: + +:: + + module(load="mmnormalize") + action(type="mmnormalize" ruleBase="/path/to/rulebase.rb") + +The same in legacy format: + +:: + + $ModLoad mmnormalize + $mmnormalizeRuleBase /path/to/rulebase.rb + *.* :mmnormalize: diff --git a/source/configuration/modules/mmpstrucdata.rst b/source/configuration/modules/mmpstrucdata.rst new file mode 100644 index 0000000..481f2e0 --- /dev/null +++ b/source/configuration/modules/mmpstrucdata.rst @@ -0,0 +1,101 @@ +RFC5424 structured data parsing module (mmpstrucdata) +===================================================== + +**Module Name:** mmpstrucdata + +**Author:** Rainer Gerhards <rgerhards@adiscon.com> + +**Available since**: 7.5.4 + +**Description**: + +The mmpstrucdata parses the structured data of `RFC5424 <https://tools.ietf.org/html/rfc5424>`_ into the message json variable tree. The data parsed, if available, is stored under "jsonRoot!rfc5424-sd!...". Please note that only RFC5424 messages will be processed. + +The difference of RFC5424 is in the message layout: the SYSLOG-MSG part only contains the structured-data part instead of the normal message part. Further down you can find a example of a structured-data part. + +**Module Configuration Parameters**: + +Note: parameter names are case-insensitive. + +Currently none. + + + +**Action Confguration Parameters**: + +Note: parameter names are case-insensitive. + +- **jsonRoot** - default "!" + Specifies into which json container the data shall be parsed to. + +- **sd_name.lowercase** - default "on" + + Available: rsyslog 8.32.0 and above + + Specifies if sd names (SDID) shall be lowercased. If set to "on", this + is the case, if "off" than not. The default of "on" is used because that + was the traditional mode of operations. It it generally advised to + change the parameter to "off" if not otherwise required. + +**See Also** + +- `Howto anonymize messages that go to specific + files <http://www.rsyslog.com/howto-anonymize-messages-that-go-to-specific-files/>`_ + +**Caveats/Known Bugs:** + +- this module is currently experimental; feedback is appreciated +- property names are treated case-insensitive in rsyslog. As such, + RFC5424 names are treated case-insensitive as well. If such names + only differ in case (what is not recommended anyways), problems will + occur. +- structured data with duplicate SD-IDs and SD-PARAMS is not properly + processed + +**Samples:** + +Below you can find a structured data part of a random message which has three parameters. + +:: + + [exampleSDID@32473 iut="3" eventSource="Application"eventID="1011"] + + +In this snippet, we parse the message and emit all json variable to a +file with the message anonymized. Note that once mmpstrucdata has run, +access to the original message is no longer possible (execept if stored +in user variables before anonymization). + +:: + + module(load="mmpstrucdata") action(type="mmpstrucdata") + template(name="jsondump" type="string" string="%msg%: %$!%\\n") + action(type="omfile" file="/path/to/log" template="jsondump") + + +**A more practical one:** + +Take this example message (inspired by RFC5424 sample;)): + +``<34>1 2003-10-11T22:14:15.003Z mymachine.example.com su - ID47 [exampleSDID@32473 iut="3" eventSource="Application" eventID="1011"][id@2 test="tast"] BOM'su root' failed for lonvick on /dev/pts/8`` + +We apply this configuration: + +:: + + module(load="mmpstrucdata") action(type="mmpstrucdata") + template(name="sample2" type="string" string="ALL: %$!%\\nSD: + %$!RFC5424-SD%\\nIUT:%$!rfc5424-sd!exampleSDID@32473!iut%\\nRAWMSG: + %rawmsg%\\n\\n") action(type="omfile" file="/path/to/log" + template="sample2") + + + +This will output: + +``ALL: { "rfc5424-sd": { "examplesdid@32473": { "iut": "3", "eventsource": "Application", "eventid": "1011" }, "id@2": { "test": "tast" } } } SD: { "examplesdid@32473": { "iut": "3", "eventsource": "Application", "eventid": "1011" }, "id@2": { "test": "tast" } } IUT:3 RAWMSG: <34>1 2003-10-11T22:14:15.003Z mymachine.example.com su - ID47 [exampleSDID@32473 iut="3" eventSource="Application" eventID="1011"][id@2 test="tast"] BOM'su root' failed for lonvick on /dev/pts/8`` + +As you can seem, you can address each of the individual items. Note that +the case of the RFC5424 parameter names has been converted to lower +case. + diff --git a/source/configuration/modules/mmrfc5424addhmac.rst b/source/configuration/modules/mmrfc5424addhmac.rst new file mode 100644 index 0000000..d3e5333 --- /dev/null +++ b/source/configuration/modules/mmrfc5424addhmac.rst @@ -0,0 +1,93 @@ +mmrfc5424addhmac +================ + +**Module Name: mmrfc5424addhmac** + +**Author:**\ Rainer Gerhards <rgerhards@adiscon.com> + +**Available since**: 7.5.6 + +**Description**: + +This module adds a hmac to RFC5424 structured data if not already +present. This is a custom module and uses openssl as requested by the +sponsor. This works exclusively for RFC5424 formatted messages; all +others are ignored. + +If both `mmpstrucdata <mmpstrucdata.html>`_ and mmrfc5424addhmac are to +be used, the recommended calling sequence is + +#. mmrfc5424addhmac +#. mmpstrucdata + +with that sequence, the generated hash will become available for +mmpstrucdata. + + + +**Module Configuration Parameters**: + +Note: parameter names are case-insensitive. + +Currently none. + + + +**Action Confguration Parameters**: + +Note: parameter names are case-insensitive. + +- **key** + The "key" (string) to be used to generate the hmac. +- **hashfunction** + An openssl hash function name for the function to be used. This is + passed on to openssl, so see the openssl list of supported function + names. +- **sd\_id** + The RFC5424 structured data ID to be used by this module. This is + the SD-ID that will be added. Note that nothing is added if this + SD-ID is already present. + +**Verification method** + +rsyslog does not contain any tools to verify a log file (this was not +part of the custom project). So you need to write your own verifier. + +When writing the verifier, keep in mind that the log file contains +messages with the hash SD-ID included. For obvious reasons, this SD-ID +was not present when the hash was created. So before the actual +verification is done, this SD-ID must be removed, and the remaining +(original) message be verified. Also, it is important to note that the +output template must write the exact same message format that was +received. Otherwise, a verification failure will obviously occur - and +must so, because the message content actually was altered. + +So in a more formal description, verification of a message m can be done +as follows: + +#. let m' be m with the configured SD-ID removed (everything between + []). Otherwise, m' must be an exact duplicate of m. +#. call openssl's HMAC function as follows: + ``HMAC(hashfunction, key, len(key), m', len(m'), hash, &hashlen);`` + Where hashfunction and key are the configured values and hash is an + output buffer for the hash. +#. let h be the extracted hash value obtained from m within the relevant + SD-ID. Be sure to convert the hex string back to the actual byte + values. +#. now compare hash and h under consideration of the sizes. If these + values match the verification succeeds, otherwise the message was + modified. + +If you need help implementing a verifier function or want to sponsor +development of a verification tool, please simply email +`sales@adiscon.com <sales@adiscon.com>`_ for a quote. + +**See Also** + +- `How to add a HMAC to RFC5424 + messages <http://www.rsyslog.com/how-to-add-a-hmac-to-rfc5424-structured-data-messages/>`_ + +**Caveats/Known Bugs:** + +- none + diff --git a/source/configuration/modules/mmrm1stspace.rst b/source/configuration/modules/mmrm1stspace.rst new file mode 100644 index 0000000..915f026 --- /dev/null +++ b/source/configuration/modules/mmrm1stspace.rst @@ -0,0 +1,30 @@ +mmrm1stspace: First Space Modification Module +============================================= + +**Author:** Pascal Withopf <pascalwithopf1@gmail.com> + +In rfc3164 the msg begins at the first letter after the tag. It is often the +case that this is a unnecessary space. This module removes this first character +if it is a space. + +Configuration Parameters +------------------------ + +Note: parameter names are case-insensitive. + +Currently none. + +Examples +-------- + +This example receives messages over imtcp and modifies them, before sending +them to a file. + +:: + + module(load="imtcp") + module(load="mmrm1stspace") + input(type="imtcp" port="13514") + action(type="mmrm1stspace") + action(type="omfile" file="output.log") + diff --git a/source/configuration/modules/mmsequence.rst b/source/configuration/modules/mmsequence.rst new file mode 100644 index 0000000..a35599f --- /dev/null +++ b/source/configuration/modules/mmsequence.rst @@ -0,0 +1,156 @@ +Number generator and counter module (mmsequence) +================================================ + +**Module Name: mmsequence** + +**Author:**\ Pavel Levshin <pavel@levshin.spb.ru> + +**Status:**\ Non project-supported module - contact author or rsyslog +mailing list for questions + +**This module is deprecated** in v8 and solely provided for backward +compatibility reasons. It was written as a work-around for missing +global variable support in v7. Global variables are available in v8, +and at some point in time this module will entirely be removed. + +**Do not use this module for newly crafted config files.** +Use global variables instead. + + +**Available since**: 7.5.6 + +**Description**: + +This module generates numeric sequences of different kinds. It can be +used to count messages up to a limit and to number them. It can generate +random numbers in a given range. + +This module is implemented via the output module interface, so it is +called just as an action. The number generated is stored in a variable. + + + +**Action Parameters**: + +Note: parameter names are case-insensitive. + +- **mode** "random" or "instance" or "key" + + Specifies mode of the action. In "random" mode, the module generates + uniformly distributed integer numbers in a range defined by "from" + and "to". + + In "instance" mode, which is default, the action produces a counter + in range [from, to). This counter is specific to this action + instance. + + In "key" mode, the counter can be shared between multiple instances. + This counter is identified by a name, which is defined with "key" + parameter. + +- **from** [non-negative integer], default "0" + + Starting value for counters and lower margin for random generator. + +- **to** [positive integer], default "INT\_MAX" + + Upper margin for all sequences. Note that this margin is not + inclusive. When next value for a counter is equal or greater than + this parameter, the counter resets to the starting value. + +- **step** [non-negative integer], default "1" + + Increment for counters. If step is "0", it can be used to fetch + current value without modification. The latter not applies to + "random" mode. This is useful in "key" mode or to get constant values + in "instance" mode. + +- **key** [word], default "" + + Name of the global counter which is used in this action. + +- **var** [word], default "$!mmsequence" + + Name of the variable where the number will be stored. Should start + with "$". + +**Sample**: + +:: + + # load balance + Ruleset( + name="logd" + queue.workerthreads="5" + ){ + + Action( + type="mmsequence" + mode="instance" + from="0" + to="2" + var="$.seq" + ) + + if $.seq == "0" then { + Action( + type="mmnormalize" + userawmsg="on" + rulebase="/etc/rsyslog.d/rules.rb" + ) + } else { + Action( + type="mmnormalize" + userawmsg="on" + rulebase="/etc/rsyslog.d/rules.rb" + ) + } + + # output logic here + } + # generate random numbers + action( + type="mmsequence" + mode="random" + to="100" + var="$!rndz" + ) + # count from 0 to 99 + action( + type="mmsequence" + mode="instance" + to="100" + var="$!cnt1" + ) + # the same as before but the counter is global + action( + type="mmsequence" + mode="key" + key="key1" + to="100" + var="$!cnt2" + ) + # count specific messages but place the counter in every message + if $msg contains "txt" then + action( + type="mmsequence" + mode="key" + to="100" + var="$!cnt3" + ) + else + action( + type="mmsequence" + mode="key" + to="100" + step="0" + var="$!cnt3" + key="" + ) + +**Legacy Configuration Parameters**: + +Note: parameter names are case-insensitive. + +Not supported. + diff --git a/source/configuration/modules/mmsnmptrapd.rst b/source/configuration/modules/mmsnmptrapd.rst new file mode 100644 index 0000000..0f75d8c --- /dev/null +++ b/source/configuration/modules/mmsnmptrapd.rst @@ -0,0 +1,103 @@ +mmsnmptrapd message modification module +======================================= + +**Module Name:** mmsnmptrapd + +**Author:** Rainer Gerhards <rgerhards@adiscon.com> (custom-created) + +**Multi-Ruleset Support:** since 5.8.1 + +**Description**: + +This module uses a specific configuration of snmptrapd's tag values to +obtain information of the original source system and the severity +present inside the original SNMP trap. It then replaces these fields +inside the syslog message. + +Let's look at an example. Essentially, SNMPTT will invoke something like +this: + +:: + + logger -t snmptrapd/warning/realhost Host 003c.abcd.ffff in vlan 17 is flapping between port Gi4/1 and port Gi3/2 + +This message modification module will change the tag (removing the +additional information), hostname and severity (not shown in example), +so the log entry will look as follows: + +:: + + 2011-04-21T16:43:09.101633+02:00 realhost snmptrapd: Host 003c.abcd.ffff in vlan 122 is flapping between port Gi4/1 and port Gi3/2 + +The following logic is applied to all message being processed: + +#. The module checks incoming syslog entries. If their TAG field starts + with "snmptrapd/" (configurable), they are modified, otherwise not. + If the are modified, this happens as follows: +#. It will derive the hostname from the tag field which has format + snmptrapd/severity/hostname +#. It should derive the severity from the tag field which has format + snmptrapd/severity/hostname. A configurable mapping table will be + used to drive a new severity value from that severity string. If no + mapping has been defined, the original severity is not changed. +#. It replaces the "FromHost" value with the derived value from step 2 +#. It replaces the "Severity" value with the derived value from step 3 + +Note that the placement of this module inside the configuration is +important. All actions before this modules is called will work on the +unmodified message. All messages after it's call will work on the +modified message. Please also note that there is some extra power in +case it is required: as this module is implemented via the output module +interface, a filter can be used (actually must be used) in order to tell +when it is called. Usually, the catch-all filter (\*.\*) is used, but +more specific filters are fully supported. So it is possible to define +different parameters for this module depending on different filters. It +is also possible to just run messages from one remote system through +this module, with the help of filters or multiple rulesets and ruleset +bindings. In short words, all capabilities rsyslog offers to control +output modules are also available to mmsnmptrapd. + +**Configuration Parameters**: + +Note: parameter names are case-insensitive. + +- **$mmsnmptrapdTag** [tagname] + + Tells the module which start string inside the tag to look for. The + default is "snmptrapd". Note that a slash is automatically added to + this tag when it comes to matching incoming messages. It MUST not be + given, except if two slashes are required for whatever reasons (so + "tag/" results in a check for "tag//" at the start of the tag field). + +- **$mmsnmptrapdSeverityMapping** [severitymap] + This specifies the severity mapping table. It needs to be specified + as a list. Note that due to the current config system **no + whitespace** is supported inside the list, so be sure not to use any + whitespace inside it. + The list is constructed of Severity-Name/Severity-Value pairs, + delimited by comma. Severity-Name is a case-sensitive string, e.g. + "warning" and an associated numerical value (e.g. 4). Possible values + are in the rage 0..7 and are defined in RFC5424, table 2. The given + sample would be specified as "warning/4". + If multiple instances of mmsnmptrapd are used, each instance uses + the most recently defined $mmsnmptrapdSeverityMapping before itself. + +**Caveats/Known Bugs:** + +- currently none known + +**Example:** + +This enables to rewrite messages from snmptrapd and configures error and +warning severities. The default tag is used. + +:: + + $ModLoad mmsnmptrapd # needs to be done just once + # ... other module loads and listener setup ... + *.* /path/to/file/with/originalMessage # this file receives unmodified messages + $mmsnmptrapdSeverityMapping warning/4,error/3 + *.* :mmsnmptrapd: # now message is modified + *.* /path/to/file/with/modifiedMessage # this file receives modified messages + # ... rest of config ... + diff --git a/source/configuration/modules/mmtaghostname.rst b/source/configuration/modules/mmtaghostname.rst new file mode 100644 index 0000000..114f723 --- /dev/null +++ b/source/configuration/modules/mmtaghostname.rst @@ -0,0 +1,89 @@ +****************************************** +mmtaghostname: message modification module +****************************************** + +================ ============================================================== +**Module Name:** **mmtaghostname** +**Authors:** Jean-Philippe Hilaire <jean-philippe.hilaire@pmu.fr> & Philippe Duveau <philippe.duveau@free.fr> +================ ============================================================== + + +Purpose +======= + +As a message modification, it can be used in a different step of the +message processing without interfering in the parsers' chain process +and can be applied before or after parsing process using rulesets. + +The purposes are : + +- to add a tag on message produce by input module which does not provide + a tag like imudp or imtcp. Useful when the tag is used for routing the + message. + +- to force message hostname to the rsyslog valeur. + AWS Use case : applications in auto-scaling systems provides logs to rsyslog + through udp/tcp. As a result of auto-scaling, the name of the host is based + on an ephemeral IPs (short term meaning). In this situation rsyslog local + hostname is generally closed to business rule. So replacing hostanme received + by the rsyslog local Hostname provide values to the logs collected. + +Compile +======= + +To successfully compile mmtaghostname module. + +.. code-block:: none + + ./configure --enable-mmtaghostname ... + +Configuration Parameters +======================== + +Tag +^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "no", ,"none" + +The tag to be assigned to messages modified. If you would like to see the +colon after the tag, you need to include it when you assign a tag value, +like so: ``tag="myTagValue:"``. + +If this attribute is no provided, messages tags are not modified. + +ForceLocalHostname +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "Binary", "no", ,"off" + +This attribute force to set the HOSTNAME of the message to the rsyslog +value "localHostName". This allow to set a valid value to message received +received from local application through imudp or imtcp. + +Sample +====== + +In this sample, the message received is parsed by RFC5424 parser and then +the HOSTNAME is overwritten and a tag is setted. + +.. code-block:: none + + module(load='mmtaghostname') + module(load='imudp') + global(localhostname="sales-front") + + ruleset(name="TagUDP" parser=[ "rsyslog.rfc5424" ]) { + action(type="mmtaghostname" tag="front" forcelocalhostname="on") + call ... + } + input(type="imudp" port="514" ruleset="TagUDP") diff --git a/source/configuration/modules/mmutf8fix.rst b/source/configuration/modules/mmutf8fix.rst new file mode 100644 index 0000000..594bb90 --- /dev/null +++ b/source/configuration/modules/mmutf8fix.rst @@ -0,0 +1,112 @@ +Fix invalid UTF-8 Sequences (mmutf8fix) +======================================= + +**Module Name:** mmutf8fix + +**Author:** Rainer Gerhards <rgerhards@adiscon.com> + +**Available since**: 7.5.4 + +**Description**: + +The mmutf8fix module permits to fix invalid UTF-8 sequences. Most often, +such invalid sequences result from syslog sources sending in non-UTF +character sets, e.g. ISO 8859. As syslog does not have a way to convey +the character set information, these sequences are not properly handled. +While they are typically uncritical with plain text files, they can +cause big headache with database sources as well as systems like +ElasticSearch. + +The module supports different "fixing" modes and fixes. The current +implementation will always replace invalid bytes with a single US ASCII +character. Additional replacement modes will probably be added in the +future, depending on user demand. In the longer term it could also be +evolved into an any-charset-to-UTF8 converter. But first let's see if it +really gets into widespread enough use. + +**Proper Usage**: + +Some notes are due for proper use of this module. This is a message +modification module utilizing the action interface, which means you call +it like an action. This gives great flexibility on the question on when +and how to call this module. Note that once it has been called, it +actually modifies the message. The original message is then no longer +available. However, this does **not** change any properties set, used or +extracted before the modification is done. + +One potential use case is to normalize all messages. This is done by +simply calling mmutf8fix right in front of all other actions. + +If only a specific source (or set of sources) is known to cause +problems, mmutf8fix can be conditionally called only on messages from +them. This also offers performance benefits. If such multiple sources +exists, it probably is a good idea to define different listeners for +their incoming traffic, bind them to specific +`ruleset <multi_ruleset.html>`_ and call mmutf8fix as first action in +this ruleset. + +**Module Configuration Parameters**: + +Note: parameter names are case-insensitive. + +Currently none. + + + +**Action Confguration Parameters**: + +Note: parameter names are case-insensitive. + +- **mode** - **utf-8**/controlcharacters + + This sets the basic detection mode. + In **utf-8** mode (the default), proper UTF-8 encoding is checked and + bytes which are not proper UTF-8 sequences are acted on. If a proper + multi-byte start sequence byte is detected but any of the following + bytes is invalid, the whole sequence is replaced by the replacement + method. This mode is most useful with non-US-ASCII character sets, + which validly includes multibyte sequences. Note that in this mode + control characters are NOT being replaced, because they are valid + UTF-8. + In **controlcharacters** mode, all bytes which do not represent a + printable US-ASCII character (codes 32 to 126) are replaced. Note + that this also mangles valid UTF-8 multi-byte sequences, as these are + (deliberately) outside of that character range. This mode is most + useful if it is known that no characters outside of the US-ASCII + alphabet need to be processed. +- **replacementChar** - default " " (space), a single character + + This is the character that invalid sequences are replaced by. + Currently, it MUST be a **printable** US-ASCII character. + +**Caveats/Known Bugs:** + +- overlong UTF-8 encodings are currently not detected in utf-8 mode. + +**Samples:** + +In this snippet, we write one file without fixing UTF-8 and another one +with the message fixed. Note that once mmutf8fix has run, access to the +original message is no longer possible. + +:: + + module(load="mmutf8fix") action(type="omfile" + file="/path/to/non-fixed.log") action(type="mmutf8fix") + action(type="omfile" file="/path/to/fixed.log") + +In this sample, we fix only message originating from host 10.0.0.1. + +:: + + module(load="mmutf8fix") if $fromhost-ip == "10.0.0.1" then + action(type="mmutf8fix") # all other actions here... + +This is mostly the same as the previous sample, but uses +"controlcharacters" processing mode. + +:: + + module(load="mmutf8fix") if $fromhost-ip == "10.0.0.1" then + action(type="mmutf8fix" mode="controlcharacters") # all other actions here... + diff --git a/source/configuration/modules/module_workflow.png b/source/configuration/modules/module_workflow.png Binary files differnew file mode 100644 index 0000000..e1a72e9 --- /dev/null +++ b/source/configuration/modules/module_workflow.png diff --git a/source/configuration/modules/omamqp1.rst b/source/configuration/modules/omamqp1.rst new file mode 100644 index 0000000..c5e2e07 --- /dev/null +++ b/source/configuration/modules/omamqp1.rst @@ -0,0 +1,476 @@ +***************************************** +omamqp1: AMQP 1.0 Messaging Output Module +***************************************** + +=========================== =========================================================================== +**Module Name:** **omamqp1** +**Available Since:** **8.17.0** +**Original Author:** Ken Giusti <kgiusti@gmail.com> +=========================== =========================================================================== + + +Purpose +======= + +This module provides the ability to send logging via an AMQP 1.0 +compliant message bus. It puts the log messages into an AMQP +message and sends the message to a destination on the bus. + + +Notable Features +================ + +- :ref:`omamqp1-message-format` +- :ref:`omamqp1-interoperability` + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + + +Action Parameters +----------------- + +Host +^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "5672", "yes", "none" + +The address of the message bus in *host[:port]* format. +The port defaults to 5672 if absent. Examples: *"localhost"*, +*"127.0.0.1:9999"*, *"bus.someplace.org"* + + +Target +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "yes", "none" + +The destination for the generated messages. This can be +the name of a queue or topic. On some messages buses it may be +necessary to create this target manually. Example: *"amq.topic"* + + +Username +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +Used by SASL to authenticate with the message bus. + + +Password +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +Used by SASL to authenticate with the message bus. + + +Template +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "RSYSLOG_FileFormat", "no", "none" + +Format for the log messages. + + +idleTimeout +^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "none" + +The idle timeout in seconds. This enables connection +heartbeats and is used to detect a failed connection to the message +bus. Set to zero to disable. + + +reconnectDelay +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "5", "no", "none" + +The time in seconds this module will delay before +attempting to re-established a failed connection to the message bus. + + +MaxRetries +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "10", "no", "none" + +The number of times an undeliverable message is +re-sent to the message bus before it is dropped. This is unrelated +to rsyslog's action.resumeRetryCount. Once the connection to the +message bus is active this module is ready to receive log messages +from rsyslog (i.e. the module has 'resumed'). Even though the +connection is active, any particular message may be rejected by the +message bus (e.g. 'unrouteable'). The module will retry +(e.g. 'suspend') for up to *maxRetries* attempts before discarding +the message as undeliverable. Setting this to zero disables the +limit and unrouteable messages will be retried as long as the +connection stays up. You probably do not want that to +happen. + + +DisableSASL +^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "none" + +Setting this to a non-zero value will disable SASL +negotiation. Only necessary if the message bus does not offer SASL +support. + + +Dependencies +============ + +* `libqpid-proton <http://qpid.apache.org/proton>`_ + +Configure +========= + +.. code-block:: none + + ./configure --enable-omamqp1 + + +.. _omamqp1-message-format: + +Message Format +============== + +Messages sent from this module to the message bus contain an AMQP List +in the message body. This list contains one or more log messages as +AMQP String types. Each string entry is a single log message. The +list is ordered such that the oldest log appears at the front of the +list (e.g. list index 0), whilst the most recent log is at the end of +the list. + + +.. _omamqp1-interoperability: + +Interoperability +================ + +The output plugin has been tested against the following messaging systems: + +* `QPID C++ Message Broker <http://qpid.apache.org/components/cpp-broker>`_ +* `QPID Dispatch Message Router <http://qpid.apache.org/components/dispatch-router>`_ + + +TODO +==== + +- Add support for SSL connections. + + +Examples +======== + +Example 1 +--------- + +This example shows a minimal configuration. The module will attempt +to connect to a QPID broker at *broker.amqp.org*. Messages are +sent to the *amq.topic* topic, which exists on the broker by default: + +.. code-block:: none + + module(load="omamqp1") + action(type="omamqp1" + host="broker.amqp.org" + target="amq.topic") + + +Example 2 +--------- + +This example forces rsyslogd to authenticate with the message bus. +The message bus must be provisioned such that user *joe* is allowed to +send to the message bus. All messages are sent to *log-queue*. It is +assumed that *log-queue* has already been provisioned: + +.. code-block:: none + + module(load="omamqp1") + + action(type="omamqp1" + host="bus.amqp.org" + target="log-queue" + username="joe" + password="trustno1") + + +Notes on use with the QPID C++ broker (qpidd) +============================================= + +*Note well*: These notes assume use of version 0.34 of the QPID C++ +broker. Previous versions may not be fully compatible. + +To use the Apache QPID C++ broker **qpidd** as the message bus, a +version of qpidd that supports the AMQP 1.0 protocol must be used. + +Since qpidd can be packaged without AMQP 1.0 support you should verify +AMQP 1.0 has been enabled by checking for AMQP 1.0 related options in +the qpidd help text. For example: + +.. code-block:: none + + qpidd --help + + ... + + AMQP 1.0 Options: + --domain DOMAIN Domain of this broker + --queue-patterns PATTERN Pattern for on-demand queues + --topic-patterns PATTERN Pattern for on-demand topics + + +If no AMQP 1.0 related options appear in the help output then your +instance of qpidd does not support AMQP 1.0 and cannot be used with +this output module. + +The destination for message (target) *must* be created before log +messages arrive. This can be done using the qpid-config tool. + +Example: + +.. code-block:: none + + qpid-config add queue rsyslogd + + +Alternatively the target can be created on demand by configuring a +queue-pattern (or topic-pattern) that matches the target. To do this, +add a *queue-patterns* or *topic_patterns* configuration directive to +the qpidd configuration file /etc/qpid/qpidd.conf. + +For example to have qpidd automatically create a queue named +*rsyslogd* add the following to the qpidd configuration file: + +.. code-block:: none + + queue-patterns=rsyslogd + + +or, if a topic behavior is desired instead of a queue: + +.. code-block:: none + + topic-patterns=rsyslogd + + +These dynamic targets are auto-delete and will be destroyed once there +are no longer any subscribers or queue-bound messages. + +Versions of qpidd <= 0.34 also need to have the SASL service name set +to *"amqp"* if SASL authentication is used. Add this to the qpidd.conf +file: + +.. code-block:: none + + sasl-service-name=amqp + + +Notes on use with the QPID Dispatch Router (qdrouterd) +====================================================== + +*Note well*: These notes assume use of version 0.5 of the QPID Dispatch +Router **qdrouterd**. Previous versions may not be fully compatible. + +The default qdrouterd configuration does not have SASL authentication +turned on. If SASL authentication is required you must configure SASL +in the qdrouter configuration file /etc/qpid-dispatch/qdrouterd.conf + +First create a SASL configuration file for qdrouterd. This +configuration file is usually /etc/sasl2/qdrouterd.conf, but its +default location may vary depending on your platform's configuration. + +This document assumes you understand how to properly configure Cyrus +SASL. + +Here is an example qdrouterd SASL configuration file that allows the +client to use either the **DIGEST-MD5** or **PLAIN** authentication +mechanisms and specifies the path to the SASL user credentials +database: + +.. code-block:: none + + pwcheck_method: auxprop + auxprop_plugin: sasldb + sasldb_path: /var/lib/qdrouterd/qdrouterd.sasldb + mech_list: DIGEST-MD5 PLAIN + + +Once a SASL configuration file has been set up for qdrouterd the path +to the directory holding the configuration file and the name of the +configuration file itself **without the '.conf' suffix** must be added +to the /etc/qpid-dispatch/qdrouterd.conf configuration file. This is +done by adding *saslConfigPath* and *saslConfigName* to the +*container* section of the configuration file. For example, assuming +the file /etc/sasl2/qdrouterd.conf holds the qdrouterd SASL +configuration: + +.. code-block:: none + + container { + workerThreads: 4 + containerName: Qpid.Dispatch.Router.A + saslConfigPath: /etc/sasl2 + saslConfigName: qdrouterd + } + + +In addition the address used by the omamqp1 module to connect to +qdrouterd must have SASL authentication turned on. This is done by +adding the *authenticatePeer* attribute set to 'yes' to the +corresponding *listener* entry: + +.. code-block:: none + + listener { + addr: 0.0.0.0 + port: amqp + authenticatePeer: yes + } + + +This should complete the SASL setup needed by qdrouterd. + +The target address used as the destination for the log messages must +be picked with care. qdrouterd uses the prefix of the target address +to determine the forwarding pattern used for messages sent to that +target address. Addresses starting with the prefix *queue* are +distributed to only one message receiver. If there are multiple +message consumers listening to that target address only one listener +will receive the message - mimicking the behavior of a queue with +competing subscribers. For example: *queue/rsyslogd* + +If a multicast pattern is desired - where all active listeners receive +their own copy of the message - the target address prefix *multicast* +may be used. For example: *multicast/rsyslogd* + +Note well: if there are no active receivers for the log messages the +messages will be rejected by qdrouterd since the messages are +undeliverable. In this case the omamqp1 module will return a +**SUSPENDED** status to the rsyslogd main task. rsyslogd may then +re-submit the rejected log messages to the module which will attempt +to send them again. This retry option is configured via rsyslogd - it +is not part of this module. Refer to the rsyslogd actions +documentation. + + +Using qdrouterd in combination with qpidd +========================================= + +A qdrouterd-based message bus can use a broker as a message storage +mechanism for those that require broker-based message services (such +as a message store). This section explains how to configure qdrouterd +and qpidd for this type of deployment. Please read the above notes +for deploying qpidd and qdrouterd first. + +Each qdrouterd instance that is to connect the broker to the message +bus must define a *connector* section in the qdrouterd.conf file. +This connector contains the addressing information necessary to have +the message bus set up a connection to the broker. For example, if a +broker is available on host broker.host.com at port 5672: + +.. code-block:: none + + connector { + name: mybroker + role: on-demand + addr: broker.host.com + port: 5672 + } + + +In order to route messages to and from the broker, a static *link +route* must be configured on qdrouterd. This link route contains a +target address prefix and the name of the connector to use for +forwarding matching messages. + +For example, to have qdrouterd forward messages that have a target +address prefixed by "Broker" to the connector defined above, the +following link pattern must be added to the qdrouterd.conf +configuration: + +.. code-block:: none + + linkRoutePattern { + prefix: /Broker/ + connector: mybroker + } + + +A queue must then be created on the broker. The name of the queue +must be prefixed by the same prefix specified in the linkRoutePattern +entry. For example: + +.. code-block:: none + + $ qpid-config add queue Broker/rsyslogd + + +Lastly use the name of the queue for the target address for the omamqp +module action. For example, assuming qdrouterd is listening on local +port 5672: + +.. code-block:: none + + action(type="omamqp1" + host="localhost:5672" + target="Broker/rsyslogd") + + diff --git a/source/configuration/modules/omazureeventhubs.rst b/source/configuration/modules/omazureeventhubs.rst new file mode 100644 index 0000000..2c27660 --- /dev/null +++ b/source/configuration/modules/omazureeventhubs.rst @@ -0,0 +1,412 @@ +********************************************************** +omazureeventhubs: Microsoft Azure Event Hubs Output Module +********************************************************** + +=========================== =========================================================================== +**Module Name:** **omazureeventhubs** +**Author:** Andre Lorbach <alorbach@adiscon.com> +**Available since:** v8.2304 +=========================== =========================================================================== + + +Purpose +======= + +The purpose of the rsyslog output plugin omazureeventhubs is to provide a +fast and reliable way to send log data from rsyslog to Microsoft Azure Event Hubs. +This plugin uses the Advanced Message Queuing Protocol (AMQP) to securely transmit +log data from rsyslog to Microsoft Azure, where it can be centralized, analyzed, and stored. +The plugin uses the "Qpid Proton C API" library to implement the AMQP protocol, +providing a flexible and efficient solution for sending log data to Microsoft Azure Event Hubs. + +AMQP is a reliable and secure binary protocol for exchanging messages between applications, +and it is widely used in the cloud and enterprise messaging systems. The use of AMQP in the +omazureeventhubs plugin, in combination with the Qpid Proton C API library, ensures that +log data is transmitted in a robust and reliable manner, even in the presence of network +outages or other disruptions. + +The omazureeventhubs plugin supports various configuration options, allowing organizations to +customize their log data pipeline to meet their specific requirements. +This includes options for specifying the Event Hubs endpoint, port, and authentication credentials. +With this plugin, organizations can easily integrate their rsyslog infrastructure with +Microsoft Azure Event Hubs, providing a scalable and secure solution for log management. +The plugin is designed to work with the latest versions of rsyslog and Microsoft Azure, +ensuring compatibility and reliability. + + +Requirements +============ + +To output logs from rsyslog to Microsoft Azure Event Hubs, you will need to fulfill the +following requirements: + +- Qpid Proton C Library Version 0.13 or higher including Qpid Proton ProActor +- The AMQP Protocol needs to have firewall Ports 5671 and 443 TCP to be open for outgoing connections. + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + + +Action Parameters +----------------- + +azurehost +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "yes", "none" + +Specifies the fully qualified domain name (FQDN) of the Event Hubs instance that +the rsyslog output plugin should connect to. The format of the hostname should +be **<namespace>.servicebus.windows.net**, where **<namespace>** is the name +of the Event Hubs namespace that was created in Microsoft Azure. + + +azureport +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "5671", "no", "none" + +Specifies the TCP port number used by the Event Hubs instance for incoming connections. +The default port number for Event Hubs is 5671 for connections over the +AMQP Secure Sockets Layer (SSL) protocol. This property is usually optional in the configuration +file of the rsyslog output plugin, as the default value of 5671 is typically used. + + +azure_key_name +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive", "Available since" + :widths: auto + :class: parameter-table + + "word", "none", "yes", "none" + +The configuration property for the Azure key name used to connect to Microsoft Azure Event Hubs is +typically referred to as the "Event Hubs shared access key name". It specifies the name of +the shared access key that is used to authenticate and authorize connections to the Event Hubs instance. +The shared access key is a secret string that is used to securely sign and validate requests +to the Event Hubs instance. + + +azure_key +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "yes", "none" + +The configuration property for the Azure key used to connect to Microsoft Azure Event Hubs is +typically referred to as the "Event Hubs shared access key". It specifies the value of the +shared access key that is used to authenticate and authorize connections to the Event Hubs instance. +The shared access key is a secret string that is used to securely sign and validate requests +to the Event Hubs instance. + + +container +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "yes", "none" + +The configuration property for the Azure container used to connect to Microsoft Azure Event Hubs is +typically referred to as the "Event Hubs Instance". It specifies the name of the Event Hubs Instance, +to which log data should be sent. + + +template +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "RSYSLOG_FileFormat", "no", "none" + +Specifies the template used to format and structure the log messages that will be sent from rsyslog to +Microsoft Azure Event Hubs. + +The message template can include rsyslog variables, such as the timestamp, hostname, or process name, +and it can use rsyslog macros, such as $rawmsg or $json, to control the formatting of log data. + +For a message template sample with valid JSON output see the sample below: + +.. code-block:: none + + template(name="generic" type="list" option.jsonf="on") { + property(outname="timestamp" name="timereported" dateFormat="rfc3339" format="jsonf") + constant(value="\"source\": \"EventHubMessage\", ") + property(outname="host" name="hostname" format="jsonf") + property(outname="severity" name="syslogseverity" caseConversion="upper" format="jsonf" datatype="number") + property(outname="facility" name="syslogfacility" format="jsonf" datatype="number") + property(outname="appname" name="syslogtag" format="jsonf") + property(outname="message" name="msg" format="jsonf" ) + property(outname="etlsource" name="$myhostname" format="jsonf") + } + + +amqp_address +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +The configuration property for the AMQP address used to connect to Microsoft Azure Event Hubs is +typically referred to as the "Event Hubs connection string". It specifies the URL that is used to connect +to the target Event Hubs instance in Microsoft Azure. If the amqp_address is configured, the configuration +parameters for **azurehost**, **azureport**, **azure_key_name** and **azure_key** will be ignored. + +A sample Event Hubs connection string URL is: + +.. code-block:: none + + amqps://[Shared access key name]:[Shared access key]@[Event Hubs namespace].servicebus.windows.net/[Event Hubs Instance] + + +eventproperties +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "array", "none", "no", "none" + +The **eventproperties** configuration property is an array property used to add key-value pairs as additional properties to the +encoded AMQP message object, providing additional information about the log event. +These properties can be used for filtering, routing, and grouping log events in Azure Event Hubs. + +The event properties property is specified as a list of key-value pairs separated by comma, +with the key and value separated by an equal sign. + +For example, the following configuration setting adds two event properties: + +.. code-block:: none + + eventproperties=[ "Table=TestTable", + "Format=JSON"] + +In this example, the Table and Format keys are added to the message object as event properties, +with the corresponding values of TestTable and JSON, respectively. + + +closeTimeout +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "2000", "no", "none" + +The close timeout configuration property is used in the rsyslog output module +to specify the amount of time the output module should wait for a response +from Microsoft Azure Event Hubs before timing out and closing the connection. + +This property is used to control the amount of time the output module will wait +for a response from the target Event Hubs instance before giving up and +assuming that the connection has failed. The close timeout property is specified in milliseconds. + + +statsname +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "omazureeventhubs", "no", "none" + +The name assigned to statistics specific to this action instance. The supported set of +statistics tracked for this action instance are **submitted**, **accepted**, **failures** and **failures_other**. +See the :ref:`statistics-counter_omazureeventhubs_label` section for more details. + + +.. _statistics-counter_omazureeventhubs_label: + +Statistic Counter +================= + +This plugin maintains global :doc:`statistics <../rsyslog_statistic_counter>` for omazureeventhubs that +accumulate all action instances. The statistic origin is named "omazureeventhubs" with following counters: + + +- **submitted** - This counter tracks the number of log messages that have been submitted by the rsyslog process + to the output module for delivery to Microsoft Azure Event Hubs. + +- **accepted** - This counter tracks the number of log messages that have been successfully delivered to + Microsoft Azure Event Hubs by the output module. + +- **failures** - This counter tracks the number of log messages that have failed to be delivered to + Microsoft Azure Event Hubs due to various error conditions, such as network connectivity issues, + incorrect configuration settings, or other technical problems. This counter provides important information about + any issues that may be affecting the delivery of log data to Microsoft Azure Event Hubs. + +- **failures_other** - This counter tracks the number of log messages that have failed to be delivered due to + other error conditions, such as incorrect payload format or unexpected data. + +These statistics counters are updated in real-time by the rsyslog output module as log data is processed, +and they provide valuable information about the performance and operation of the output module. + +For multiple actions using statistics callback, there will be one record for each action. + +.. _omazureeventhubs-examples-label: + +Examples +======== + +Example 1: Use AMQP URL +----------------------- + +The following sample does the following: + +- loads the omazureeventhubs module +- outputs all logs to Microsoft Azure Event Hubs with standard template +- Uses amqp_address parameter + +.. code-block:: none + + module(load="omazureeventhubs") + action(type="omazureeventhubs" amqp_address="amqps://<AccessKeyName>:<AccessKey>@<EventHubsNamespace>.servicebus.windows.net/<EventHubsInstance>") + + +Example 2: RAW Format +--------------------- + +The following sample does the following: + +- loads the omazureeventhubs module +- outputs all logs to Microsoft Azure Event Hubs with simple custom template +- Uses **azurehost**, **azureport**, **azure_key_name** and **azure_key** + parameters instead of **amqp_address** parameter + +.. code-block:: none + + module(load="omazureeventhubs") + template(name="outfmt" type="string" string="%msg%\n") + + action(type="omazureeventhubs" + azurehost="<EventHubsNamespace>.servicebus.windows.net" + azureport="5671" + azure_key_name="<AccessKeyName>" + azure_key="<AccessKey>" + container="<EventHubsInstance>" + template="outfmt" + ) + + +Example 3: JSON Format +---------------------- + +The following sample does the following: + +- loads the omazureeventhubs module +- outputs all logs to Microsoft Azure Event Hubs with JSON custom template +- Uses **azurehost**, **azureport**, **azure_key_name** and **azure_key** + parameters instead of **amqp_address** parameter +- Uses **eventproperties** array parameter to set additional message properties + +.. code-block:: none + + module(load="omazureeventhubs") + template(name="outfmtjson" type="list" option.jsonf="on") { + property(outname="timestamp" name="timereported" dateFormat="rfc3339" format="jsonf") + constant(value="\"source\": \"EventHubMessage\", ") + property(outname="host" name="hostname" format="jsonf") + property(outname="severity" name="syslogseverity" caseConversion="upper" format="jsonf" datatype="number") + property(outname="facility" name="syslogfacility" format="jsonf" datatype="number") + property(outname="appname" name="syslogtag" format="jsonf") + property(outname="message" name="msg" format="jsonf" ) + property(outname="etlsource" name="$myhostname" format="jsonf") + } + + action(type="omazureeventhubs" + azurehost="<EventHubsNamespace>.servicebus.windows.net" + azureport="5671" + azure_key_name="<AccessKeyName>" + azure_key="<AccessKey>" + container="<EventHubsInstance>" + template="outfmtjson" + eventproperties=[ "Table=CustomTable", + "Format=JSON"] + ) + +Example 4: High Performance +--------------------------- + +To achieve high performance when sending syslog data to Azure Event Hubs, you should consider configuring your output module to use multiple worker instances. This can be done by setting the "workerthreads" parameter in the configuration file. + +The following example is for high performance (Azure Premium Tier) and does the following: + +- loads the omazureeventhubs module +- outputs all logs to Microsoft Azure Event Hubs with JSON custom template +- Uses **azurehost**, **azureport**, **azure_key_name** and **azure_key** + parameters instead of **amqp_address** parameter +- Uses **eventproperties** array parameter to set additional message properties +- Uses **Linkedlist** In-Memory Queue which enables multiple omazureeventhubs workers running at the same time. Using a dequeue size of 2000 and a dequeue timeout of 1000 has shown very good results in performance tests. +- Uses 8 workerthreads in this example, which will be spawn automatically if more than 2000 messages are waiting in the Queue. To achieve more performance, the number can be incremented. + +.. code-block:: none + + module(load="omazureeventhubs") + template(name="outfmtjson" type="list" option.jsonf="on") { + property(outname="timestamp" name="timereported" dateFormat="rfc3339" format="jsonf") + constant(value="\"source\": \"EventHubMessage\", ") + property(outname="host" name="hostname" format="jsonf") + property(outname="severity" name="syslogseverity" caseConversion="upper" format="jsonf" datatype="number") + property(outname="facility" name="syslogfacility" format="jsonf" datatype="number") + property(outname="appname" name="syslogtag" format="jsonf") + property(outname="message" name="msg" format="jsonf" ) + property(outname="etlsource" name="$myhostname" format="jsonf") + } + + action(type="omazureeventhubs" + azurehost="<EventHubsNamespace>.servicebus.windows.net" + azureport="5671" + azure_key_name="<AccessKeyName>" + azure_key="<AccessKey>" + container="<EventHubsInstance>" + template="outfmtjson" + eventproperties=[ "Table=CustomTable", + "Format=JSON"] + queue.type="linkedList" + queue.size="200000" + queue.saveonshutdown="on" + queue.dequeueBatchSize="2000" + queue.minDequeueBatchSize.timeout="1000" + queue.workerThreads="8" + queue.workerThreadMinimumMessages="2000" + queue.timeoutWorkerthreadShutdown="10000" + queue.timeoutshutdown="1000" + ) + diff --git a/source/configuration/modules/omclickhouse.rst b/source/configuration/modules/omclickhouse.rst new file mode 100644 index 0000000..499d8bd --- /dev/null +++ b/source/configuration/modules/omclickhouse.rst @@ -0,0 +1,324 @@ +************************************** +omclickhouse: ClickHouse Output Module +************************************** + +=========================== =========================================================================== +**Module Name:** **omclickhouse** +**Author:** Pascal Withopf <pwithopf@adiscon.com> +=========================== =========================================================================== + + +Purpose +======= + +This module provides native support for logging to +`ClickHouse <https://clickhouse.yandex/>`_. +To enable the module use "--enable-clickhouse" while configuring rsyslog. +Tests for the testbench can be enabled with "--enable-clickhouse-tests". + + +Notable Features +================ + +- :ref:`omclickhouse-statistic-counter` + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + + +Action Parameters +----------------- + +Server +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "localhost", "no", "none" + +The address of a ClickHouse server. + +.. _port: + +Port +^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "8123", "no", "none" + +HTTP port to use to connect to ClickHouse. + + +usehttps +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "none" + +Default scheme to use when sending events to ClickHouse if none is +specified on a server. + + +template +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "StdClickHouseFmt", "no", "none" + +This is the message format that will be sent to ClickHouse. The +resulting string needs to be a valid INSERT Query, otherwise ClickHouse +will return an error. Defaults to: + +.. code-block:: none + + "\"INSERT INTO rsyslog.SystemEvents (severity, facility, " + "timestamp, hostname, tag, message) VALUES (%syslogseverity%, %syslogfacility%, " + "'%timereported:::date-unixtimestamp%', '%hostname%', '%syslogtag%', '%msg%')\"" + + +bulkmode +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "none" + +The "off" setting means logs are shipped one by one. Each in +its own HTTP request. +The default "on" will send multiple logs in the same request. This is +recommended, because it is many times faster than when bulkmode is turned off. +The maximum number of logs sent in a single bulk request depends on your +maxbytes and queue settings - usually limited by the `dequeue batch +size <http://www.rsyslog.com/doc/node35.html>`_. More information +about queues can be found +`here <http://www.rsyslog.com/doc/node32.html>`_. + + +maxbytes +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "Size", "104857600/100mb", "no", "none" + +When shipping logs with bulkmode **on**, maxbytes specifies the maximum +size of the request body sent to ClickHouse. Logs are batched until +either the buffer reaches maxbytes or the `dequeue batch +size <http://www.rsyslog.com/doc/node35.html>`_ is reached. + + +user +^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "default", "no", "none" + +If you have basic HTTP authentication deployed you can specify your user-name here. + + +pwd +^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "", "no", "none" + +Password for basic authentication. + + +errorFile +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +If specified, records failed in bulk mode are written to this file, including +their error cause. Rsyslog itself does not process the file any more, but the +idea behind that mechanism is that the user can create a script to periodically +inspect the error file and react appropriately. As the complete request is +included, it is possible to simply resubmit messages from that script. + +*Please note:* when rsyslog has problems connecting to clickhouse, a general +error is assumed. However, if we receive negative responses during batch +processing, we assume an error in the data itself (like a mandatory field is +not filled in, a format error or something along those lines). Such errors +cannot be solved by simply resubmitting the record. As such, they are written +to the error file so that the user (script) can examine them and act appropriately. +Note that e.g. after search index reconfiguration (e.g. dropping the mandatory +attribute) a resubmit may be successful. + + +allowUnsignedCerts +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "none" + +The module accepts connections to servers, which have unsigned certificates. +If this parameter is disabled, the module will verify whether the certificates +are authentic. + + +skipverifyhost +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "boolean", "off", "no", "none" + +If `"on"`, this will set the curl `CURLOPT_SSL_VERIFYHOST` option to +`0`. You are strongly discouraged to set this to `"on"`. It is +primarily useful only for debugging or testing. + + +healthCheckTimeout +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "int", "3500", "no", "none" + +This parameter sets the timeout for checking the availability +of ClickHouse. Value is given in milliseconds. + + +timeout +^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "int", "0", "no", "none" + +This parameter sets the timeout for sending data to ClickHouse. +Value is given in milliseconds. + + +.. _omclickhouse-statistic-counter: + +Statistic Counter +================= + +This plugin maintains global :doc:`statistics <../rsyslog_statistic_counter>`, +which accumulate all action instances. The statistic is named "omclickhouse". +Parameters are: + +- **submitted** - number of messages submitted for processing (with both + success and error result) + +- **fail.httprequests** - the number of times a http request failed. Note + that a single http request may be used to submit multiple messages, so this + number may be (much) lower than failed.http. + +- **failed.http** - number of message failures due to connection like-problems + (things like remote server down, broken link etc) + +- **fail.clickhouse** - number of failures due to clickhouse error reply; Note that + this counter does NOT count the number of failed messages but the number of + times a failure occurred (a potentially much smaller number). Counting messages + would be quite performance-intense and is thus not done. + +- **response.success** - number of records successfully sent in bulk index + requests - counts the number of successful responses + + +**The fail.httprequests and failed.http counters reflect only failures that +omclickhouse detected.** Once it detects problems, it (usually, depends on +circumstances) tell the rsyslog core that it wants to be suspended until the +situation clears (this is a requirement for rsyslog output modules). Once it is +suspended, it does NOT receive any further messages. Depending on the user +configuration, messages will be lost during this period. Those lost messages will +NOT be counted by impstats (as it does not see them). + + +Examples +======== + +Example 1 +--------- + +The following sample does the following: + +- loads the omclickhouse module +- outputs all logs to ClickHouse using the default settings + +.. code-block:: none + + module(load="omclickhouse") + action(type="omclickhouse") + + +Example 2 +--------- + +In this example the URL will use http and the specified parameters to create +the REST URL. + +.. code-block:: none + + module(load="omclickhouse") + action(type="omclickhouse" server="127.0.0.1" port="8124" user="user1" pwd="pwd1" + usehttps="off") + + +Example 3 +--------- + +This example will send messages in batches up to 10MB. +If an error occurs it will be written in the error file. + +.. code-block:: none + + module(load="omclickhouse") + action(type="omclickhouse" maxbytes="10mb" errorfile="clickhouse-error.log") + + diff --git a/source/configuration/modules/omelasticsearch.rst b/source/configuration/modules/omelasticsearch.rst new file mode 100644 index 0000000..ee561fc --- /dev/null +++ b/source/configuration/modules/omelasticsearch.rst @@ -0,0 +1,1102 @@ +******************************************** +omelasticsearch: Elasticsearch Output Module +******************************************** + +=========================== =========================================================================== +**Module Name:** **omelasticsearch** +**Author:** `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com> +=========================== =========================================================================== + + +Purpose +======= + +This module provides native support for logging to +`Elasticsearch <http://www.elasticsearch.org/>`_. + + +Notable Features +================ + +- :ref:`omelasticsearch-statistic-counter` + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + + +Action Parameters +----------------- + +Server +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "array", "none", "no", "none" + +An array of Elasticsearch servers in the specified format. If no scheme +is specified, it will be chosen according to usehttps_. If no port is +specified, serverport_ will be used. Defaults to "localhost". + +Requests to Elasticsearch will be load-balanced between all servers in +round-robin fashion. + +.. code-block:: none + + Examples: + server="localhost:9200" + server=["elasticsearch1", "elasticsearch2"] + + +.. _serverport: + +Serverport +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "9200", "no", "none" + +Default HTTP port to use to connect to Elasticsearch if none is specified +on a server_. Defaults to 9200 + + +.. _healthchecktimeout: + +HealthCheckTimeout +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "3500", "no", "none" + +Specifies the number of milliseconds to wait for a successful health check +on a server_. Before trying to submit events to Elasticsearch, rsyslog will +execute an *HTTP HEAD* to ``/_cat/health`` and expect an *HTTP OK* within +this timeframe. Defaults to 3500. + +*Note, the health check is verifying connectivity only, not the state of +the Elasticsearch cluster.* + + +.. _esVersion_major: + +esVersion.major +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "none" + +ElasticSearch is notoriously bad at maintaining backwards compatibility. For this +reason, the setting can be used to configure the server's major version number (e.g. 7, 8, ...). +As far as we know breaking changes only happen with major version changes. +As of now, only value 8 triggers API changes. All other values select +pre-version-8 API usage. + +.. _searchIndex: + +searchIndex +^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +`Elasticsearch +index <http://www.elasticsearch.org/guide/appendix/glossary.html#index>`_ +to send your logs to. Defaults to "system" + + +.. _dynSearchIndex: + +dynSearchIndex +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +Whether the string provided for searchIndex_ should be taken as a +`rsyslog template <http://www.rsyslog.com/doc/rsyslog_conf_templates.html>`_. +Defaults to "off", which means the index name will be taken +literally. Otherwise, it will look for a template with that name, and +the resulting string will be the index name. For example, let's +assume you define a template named "date-days" containing +"%timereported:1:10:date-rfc3339%". Then, with dynSearchIndex="on", +if you say searchIndex="date-days", each log will be sent to and +index named after the first 10 characters of the timestamp, like +"2013-03-22". + + +.. _searchType: + +searchType +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +`Elasticsearch +type <http://www.elasticsearch.org/guide/appendix/glossary.html#type>`_ +to send your index to. Defaults to "events". +Setting this parameter to an empty string will cause the type to be omitted, +which is required since Elasticsearch 7.0. See +`Elasticsearch documentation <https://www.elastic.co/guide/en/elasticsearch/reference/current/removal-of-types.html>`_ +for more information. + + +.. _dynSearchType: + +dynSearchType +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +Like dynSearchIndex_, it allows you to specify a +`rsyslog template <http://www.rsyslog.com/doc/rsyslog_conf_templates.html>`_ +for searchType_, instead of a static string. + + +.. _pipelineName: + +pipelineName +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +The `ingest node <https://www.elastic.co/guide/en/elasticsearch/reference/current/ingest.html>`_ +pipeline name to be included in the request. This allows pre processing +of events before indexing them. By default, events are not send to a pipeline. + + +.. _dynPipelineName: + +dynPipelineName +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +Like dynSearchIndex_, it allows you to specify a +`rsyslog template <http://www.rsyslog.com/doc/rsyslog_conf_templates.html>`_ +for pipelineName_, instead of a static string. + + +.. _skipPipelineIfEmpty: + +skipPipelineIfEmpty +^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +When POST'ing a document, Elasticsearch does not allow an empty pipeline +parameter value. If boolean option skipPipelineIfEmpty is set to `"on"`, the +pipeline parameter won't be posted. Default is `"off"`. + + +.. _asyncrepl: + +asyncrepl +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +No longer supported as ElasticSearch no longer supports it. + + +.. _usehttps: + +usehttps +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +Default scheme to use when sending events to Elasticsearch if none is +specified on a server_. Good for when you have +Elasticsearch behind Apache or something else that can add HTTPS. +Note that if you have a self-signed certificate, you'd need to install +it first. This is done by copying the certificate to a trusted path +and then running *update-ca-certificates*. That trusted path is +typically */usr/local/share/ca-certificates* but check the man page of +*update-ca-certificates* for the default path of your distro + + +.. _timeout: + +timeout +^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "1m", "no", "none" + +How long Elasticsearch will wait for a primary shard to be available +for indexing your log before sending back an error. Defaults to "1m". + + +.. _indextimeout: + +indexTimeout +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "none" + +.. versionadded:: 8.2204.0 + +Specifies the number of milliseconds to wait for a successful log indexing +request on a server_. By default there is no timeout. + + +.. _template: + +template +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "see below", "no", "none" + +This is the JSON document that will be indexed in Elasticsearch. The +resulting string needs to be a valid JSON, otherwise Elasticsearch +will return an error. Defaults to: + +.. code-block:: none + + $template StdJSONFmt, "{\"message\":\"%msg:::json%\",\"fromhost\":\"%HOSTNAME:::json%\",\"facility\":\"%syslogfacility-text%\",\"priority\":\"%syslogpriority-text%\",\"timereported\":\"%timereported:::date-rfc3339%\",\"timegenerated\":\"%timegenerated:::date-rfc3339%\"}" + +Which will produce this sort of documents (pretty-printed here for +readability): + +.. code-block:: none + + { + "message": " this is a test message", + "fromhost": "test-host", + "facility": "user", + "priority": "info", + "timereported": "2013-03-12T18:05:01.344864+02:00", + "timegenerated": "2013-03-12T18:05:01.344864+02:00" + } + +Another template, FullJSONFmt, is available that includes more fields including programname, PROCID (usually the process ID), and MSGID. + +.. _bulkmode: + +bulkmode +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +The default "off" setting means logs are shipped one by one. Each in +its own HTTP request, using the `Index +API <http://www.elasticsearch.org/guide/reference/api/index_.html>`_. +Set it to "on" and it will use Elasticsearch's `Bulk +API <http://www.elasticsearch.org/guide/reference/api/bulk.html>`_ to +send multiple logs in the same request. The maximum number of logs +sent in a single bulk request depends on your maxbytes_ +and queue settings - +usually limited by the `dequeue batch +size <http://www.rsyslog.com/doc/node35.html>`_. More information +about queues can be found +`here <http://www.rsyslog.com/doc/node32.html>`_. + + +.. _maxbytes: + +maxbytes +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "100m", "no", "none" + +.. versionadded:: 8.23.0 + +When shipping logs with bulkmode_ **on**, maxbytes specifies the maximum +size of the request body sent to Elasticsearch. Logs are batched until +either the buffer reaches maxbytes or the `dequeue batch +size <http://www.rsyslog.com/doc/node35.html>`_ is reached. In order to +ensure Elasticsearch does not reject requests due to content length, verify +this value is set according to the `http.max_content_length +<https://www.elastic.co/guide/en/elasticsearch/reference/current/modules-http.html>`_ +setting in Elasticsearch. Defaults to 100m. + + +.. _parent: + +parent +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +Specifying a string here will index your logs with that string the +parent ID of those logs. Please note that you need to define the +`parent +field <http://www.elasticsearch.org/guide/reference/mapping/parent-field.html>`_ +in your +`mapping <http://www.elasticsearch.org/guide/reference/mapping/>`_ +for that to work. By default, logs are indexed without a parent. + + +.. _dynParent: + +dynParent +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +Using the same parent for all the logs sent in the same action is +quite unlikely. So you'd probably want to turn this "on" and specify +a +`rsyslog template <http://www.rsyslog.com/doc/rsyslog_conf_templates.html>`_ +that will provide meaningful parent IDs for your logs. + + +.. _uid: + +uid +^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +If you have basic HTTP authentication deployed (eg through the +`elasticsearch-basic +plugin <https://github.com/Asquera/elasticsearch-http-basic>`_), you +can specify your user-name here. + + +.. _pwd: + +pwd +^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +Password for basic authentication. + + +.. _errorfile: + +errorFile +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +If specified, records failed in bulk mode are written to this file, including +their error cause. Rsyslog itself does not process the file any more, but the +idea behind that mechanism is that the user can create a script to periodically +inspect the error file and react appropriately. As the complete request is +included, it is possible to simply resubmit messages from that script. + +*Please note:* when rsyslog has problems connecting to elasticsearch, a general +error is assumed and the submit is retried. However, if we receive negative +responses during batch processing, we assume an error in the data itself +(like a mandatory field is not filled in, a format error or something along +those lines). Such errors cannot be solved by simply resubmitting the record. +As such, they are written to the error file so that the user (script) can +examine them and act appropriately. Note that e.g. after search index +reconfiguration (e.g. dropping the mandatory attribute) a resubmit may +be successful. + +.. _omelasticsearch-tls.cacert: + +tls.cacert +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +This is the full path and file name of the file containing the CA cert for the +CA that issued the Elasticsearch server cert. This file is in PEM format. For +example: `/etc/rsyslog.d/es-ca.crt` + +.. _tls.mycert: + +tls.mycert +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +This is the full path and file name of the file containing the client cert for +doing client cert auth against Elasticsearch. This file is in PEM format. For +example: `/etc/rsyslog.d/es-client-cert.pem` + +.. _tls.myprivkey: + +tls.myprivkey +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +This is the full path and file name of the file containing the private key +corresponding to the cert `tls.mycert` used for doing client cert auth against +Elasticsearch. This file is in PEM format, and must be unencrypted, so take +care to secure it properly. For example: `/etc/rsyslog.d/es-client-key.pem` + +.. _omelasticsearch-allowunsignedcerts: + +allowunsignedcerts +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "boolean", "off", "no", "none" + +If `"on"`, this will set the curl `CURLOPT_SSL_VERIFYPEER` option to +`0`. You are strongly discouraged to set this to `"on"`. It is +primarily useful only for debugging or testing. + +.. _omelasticsearch-skipverifyhost: + +skipverifyhost +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "boolean", "off", "no", "none" + +If `"on"`, this will set the curl `CURLOPT_SSL_VERIFYHOST` option to +`0`. You are strongly discouraged to set this to `"on"`. It is +primarily useful only for debugging or testing. + +.. _omelasticsearch-bulkid: + +bulkid +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +This is the unique id to assign to the record. The `bulk` part is misleading - this +can be used in both bulk mode :ref:`bulkmode` or in index +(record at a time) mode. Although you can specify a static value for this +parameter, you will almost always want to specify a *template* for the value of +this parameter, and set `dynbulkid="on"` :ref:`omelasticsearch-dynbulkid`. NOTE: +you must use `bulkid` and `dynbulkid` in order to use `writeoperation="create"` +:ref:`omelasticsearch-writeoperation`. + +.. _omelasticsearch-dynbulkid: + +dynbulkid +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +If this parameter is set to `"on"`, then the `bulkid` parameter :ref:`omelasticsearch-bulkid` +specifies a *template* to use to generate the unique id value to assign to the record. If +using `bulkid` you will almost always want to set this parameter to `"on"` to assign +a different unique id value to each record. NOTE: +you must use `bulkid` and `dynbulkid` in order to use `writeoperation="create"` +:ref:`omelasticsearch-writeoperation`. + +.. _omelasticsearch-writeoperation: + +writeoperation +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "index", "no", "none" + +The value of this parameter is either `"index"` (the default) or `"create"`. If `"create"` is +used, this means the bulk action/operation will be `create` - create a document only if the +document does not already exist. The record must have a unique id in order to use `create`. +See :ref:`omelasticsearch-bulkid` and :ref:`omelasticsearch-dynbulkid`. See +:ref:`omelasticsearch-writeoperation-example` for an example. + +.. _omelasticsearch-retryfailures: + +retryfailures +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +If this parameter is set to `"on"`, then the module will look for an +`"errors":true` in the bulk index response. If found, each element in the +response will be parsed to look for errors, since a bulk request may have some +records which are successful and some which are failures. Failed requests will +be converted back into records and resubmitted back to rsyslog for +reprocessing. Each failed request will be resubmitted with a local variable +called `$.omes`. This is a hash consisting of the fields from the metadata +header in the original request, and the fields from the response. If the same +field is in the request and response, the value from the field in the *request* +will be used, to facilitate retries that want to send the exact same request, +and want to know exactly what was sent. +See below :ref:`omelasticsearch-retry-example` for an example of how retry +processing works. +*NOTE* The retried record will be resubmitted at the "top" of your processing +pipeline. If your processing pipeline is not idempotent (that is, your +processing pipeline expects "raw" records), then you can specify a ruleset to +redirect retries to. See :ref:`omelasticsearch-retryruleset` below. + +`$.omes` fields: + +* writeoperation - the operation used to submit the request - for rsyslog + omelasticsearch this currently means either `"index"` or `"create"` +* status - the HTTP status code - typically an error will have a `4xx` or `5xx` + code - of particular note is `429` - this means Elasticsearch was unable to + process this bulk record request due to a temporary condition e.g. the bulk + index thread pool queue is full, and rsyslog should retry the operation. +* _index, _type, _id, pipeline, _parent - the metadata associated with the + request - not all of these fields will be present with every request - for + example, if you do not use `"pipelinename"` or `"dynpipelinename"`, there + will be no `$.omes!pipeline` field. +* error - a hash containing one or more, possibly nested, fields containing + more detailed information about a failure. Typically there will be fields + `$.omes!error!type` (a keyword) and `$.omes!error!reason` (a longer string) + with more detailed information about the rejection. NOTE: The format is + apparently not described in great detail, so code must not make any + assumption about the availability of `error` or any specific sub-field. + +There may be other fields too - the code just copies everything in the +response. Here is an example of a detailed error response, in JSON format, from +Elasticsearch 5.6.9: + +.. code-block:: json + + {"omes": + {"writeoperation": "create", + "_index": "rsyslog_testbench", + "_type": "test-type", + "_id": "92BE7AF79CD44305914C7658AF846A08", + "status": 400, + "error": + {"type": "mapper_parsing_exception", + "reason": "failed to parse [msgnum]", + "caused_by": + {"type": "number_format_exception", + "reason": "For input string: \"x00000025\""}}}} + +Reference: https://www.elastic.co/guide/en/elasticsearch/guide/current/bulk.html#bulk + +.. _omelasticsearch-retryruleset: + +retryruleset +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "", "no", "none" + +If `retryfailures` is not `"on"` (:ref:`omelasticsearch-retryfailures`) then +this parameter has no effect. This parameter specifies the name of a ruleset +to use to route retries. This is useful if you do not want retried messages to +be processed starting from the top of your processing pipeline, or if you have +multiple outputs but do not want to send retried Elasticsearch failures to all +of your outputs, and you do not want to clutter your processing pipeline with a +lot of conditionals. See below :ref:`omelasticsearch-retry-example` for an +example of how retry processing works. + +.. _omelasticsearch-ratelimit.interval: + +ratelimit.interval +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "600", "no", "none" + +If `retryfailures` is not `"on"` (:ref:`omelasticsearch-retryfailures`) then +this parameter has no effect. Specifies the interval in seconds onto which +rate-limiting is to be applied. If more than ratelimit.burst messages are read +during that interval, further messages up to the end of the interval are +discarded. The number of messages discarded is emitted at the end of the +interval (if there were any discards). +Setting this to value zero turns off ratelimiting. + +.. _omelasticsearch-ratelimit.burst: + +ratelimit.burst +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "20000", "no", "none" + +If `retryfailures` is not `"on"` (:ref:`omelasticsearch-retryfailures`) then +this parameter has no effect. Specifies the maximum number of messages that +can be emitted within the ratelimit.interval interval. For further information, +see description there. + +.. _omelasticsearch-rebindinterval: + +rebindinterval +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "-1", "no", "none" + +This parameter tells omelasticsearch to close the connection and reconnect +to Elasticsearch after this many operations have been submitted. The default +value `-1` means that omelasticsearch will not reconnect. A value greater +than `-1` tells omelasticsearch, after this many operations have been +submitted to Elasticsearch, to drop the connection and establish a new +connection. This is useful when rsyslog connects to multiple Elasticsearch +nodes through a router or load balancer, and you need to periodically drop +and reestablish connections to help the router balance the connections. Use +the counter `rebinds` to monitor the number of times this has happened. + +.. _omelasticsearch-statistic-counter: + +Statistic Counter +================= + +This plugin maintains global :doc:`statistics <../rsyslog_statistic_counter>`, +which accumulate all action instances. The statistic is named "omelasticsearch". +Parameters are: + +- **submitted** - number of messages submitted for processing (with both + success and error result) + +- **fail.httprequests** - the number of times a http request failed. Note + that a single http request may be used to submit multiple messages, so this + number may be (much) lower than fail.http. + +- **fail.http** - number of message failures due to connection like-problems + (things like remote server down, broken link etc) + +- **fail.es** - number of failures due to elasticsearch error reply; Note that + this counter does NOT count the number of failed messages but the number of + times a failure occurred (a potentially much smaller number). Counting messages + would be quite performance-intense and is thus not done. + +The following counters are available when `retryfailures="on"` is used: + +- **response.success** - number of records successfully sent in bulk index + requests - counts the number of successful responses + +- **response.bad** - number of times omelasticsearch received a response in a + bulk index response that was unrecognized or unable to be parsed. This may + indicate that omelasticsearch is attempting to communicate with a version of + Elasticsearch that is incompatible, or is otherwise sending back data in the + response that cannot be handled + +- **response.duplicate** - number of records in the bulk index request that + were duplicates of already existing records - this will only be reported if + using `writeoperation="create"` and `bulkid` to assign each record a unique + ID + +- **response.badargument** - number of times omelasticsearch received a + response that had a status indicating omelasticsearch sent bad data to + Elasticsearch. For example, status `400` and an error message indicating + omelasticsearch attempted to store a non-numeric string value in a numeric + field. + +- **response.bulkrejection** - number of times omelasticsearch received a + response that had a status indicating Elasticsearch was unable to process + the record at this time - status `429`. The record can be retried. + +- **response.other** - number of times omelasticsearch received a + response not recognized as one of the above responses, typically some other + `4xx` or `5xx` http status. + +- **rebinds** - if using `rebindinterval` this will be the number of + times omelasticsearch has reconnected to Elasticsearch + +**The fail.httprequests and fail.http counters reflect only failures that +omelasticsearch detected.** Once it detects problems, it (usually, depends on +circumstances) tell the rsyslog core that it wants to be suspended until the +situation clears (this is a requirement for rsyslog output modules). Once it is +suspended, it does NOT receive any further messages. Depending on the user +configuration, messages will be lost during this period. Those lost messages will +NOT be counted by impstats (as it does not see them). + +Note that some previous (pre 7.4.5) versions of this plugin had different counters. +These were experimental and confusing. The only ones really used were "submits", +which were the number of successfully processed messages and "connfail" which were +equivalent to "failed.http". + +How Retries Are Handled +======================= + +When using `retryfailures="on"` (:ref:`omelasticsearch-retryfailures`), the +original `Message` object (that is, the original `smsg_t *msg` object) **is not +available**. This means none of the metadata associated with that object, such +as various timestamps, hosts/ip addresses, etc. are not available for the retry +operation. The only thing available are the metadata header (_index, _type, +_id, pipeline, _parent) and original JSON string sent in the original request, +and whatever data is returned in the error response. All of these are made +available in the `$.omes` fields. If the same field name exists in the request +metadata and the response, the field from the request will be used, in order to +facilitate retrying the exact same request. For the message to retry, the code +will take the original JSON string and parse it back into an internal `Message` +object. This means you **may need to use a different template** to output +messages for your retry ruleset. For example, if you used the following +template to format the Elasticsearch message for the initial submission: + +.. code-block:: none + + template(name="es_output_template" + type="list" + option.json="on") { + constant(value="{") + constant(value="\"timestamp\":\"") property(name="timereported" dateFormat="rfc3339") + constant(value="\",\"message\":\"") property(name="msg") + constant(value="\",\"host\":\"") property(name="hostname") + constant(value="\",\"severity\":\"") property(name="syslogseverity-text") + constant(value="\",\"facility\":\"") property(name="syslogfacility-text") + constant(value="\",\"syslogtag\":\"") property(name="syslogtag") + constant(value="\"}") + } + +You would have to use a different template for the retry, since none of the +`timereported`, `msg`, etc. fields will have the same values for the retry as +for the initial try. + +Same with the other omelasticsearch parameters which can be constructed with +templates, such as `"dynpipelinename"`, `"dynsearchindex"`, `"dynsearchtype"`, +`"dynparent"`, and `"dynbulkid"`. For example, if you generate the `_id` to +use in the request, you will want to reuse the same `_id` for each subsequent +retry: + +.. code-block:: none + + template(name="id-template" type="string" string="%$.es_msg_id%") + if strlen($.omes!_id) > 0 then { + set $.es_msg_id = $.omes!_id; + } else { + # NOTE: depends on rsyslog being compiled with --enable-uuid + set $.es_msg_id = $uuid; + } + action(type="omelasticsearch" bulkid="id-template" ...) + +That is, if this is a retry, `$.omes!_id` will be set, so use that value for +the bulk id for this record, otherwise, generate a new one with `$uuid`. Note +that the template uses the temporary variable `$.es_msg_id` which must be set +each time, to either `$.omes!_id` or `$uuid`. + +The `rawmsg` field is a special case. If the original request had a field +called `message`, then when constructing the new message from the original to +retry, the `rawmsg` message property will be set to the value of the `message` +field. Otherwise, the `rawmsg` property value will be set to the entire +original request - the data part, not the metadata. In previous versions, +without the `message` field, the `rawmsg` property was set to the value of the +data plus the Elasticsearch metadata, which caused problems with retries. See +`rsyslog issue 3573 <https://github.com/rsyslog/rsyslog/issues/3573>`_ + +Examples +======== + +Example 1 +--------- + +The following sample does the following: + +- loads the omelasticsearch module +- outputs all logs to Elasticsearch using the default settings + +.. code-block:: none + + module(load="omelasticsearch") + *.* action(type="omelasticsearch") + + +Example 2 +--------- + +The following sample does the following: + +- loads the omelasticsearch module +- outputs all logs to Elasticsearch using the full JSON logging template including program name + +.. code-block:: none + + module(load="omelasticsearch") + *.* action(type="omelasticsearch" template="FullJSONFmt") + + +Example 3 +--------- + +The following sample does the following: + +- loads the omelasticsearch module +- defines a template that will make the JSON contain the following + properties + + - RFC-3339 timestamp when the event was generated + - the message part of the event + - hostname of the system that generated the message + - severity of the event, as a string + - facility, as a string + - the tag of the event + +- outputs to Elasticsearch with the following settings + + - host name of the server is myserver.local + - port is 9200 + - JSON docs will look as defined in the template above + - index will be "test-index" + - type will be "test-type" + - activate bulk mode. For that to work effectively, we use an + in-memory queue that can hold up to 5000 events. The maximum bulk + size will be 300 + - retry indefinitely if the HTTP request failed (eg: if the target + server is down) + +.. code-block:: none + + module(load="omelasticsearch") + template(name="testTemplate" + type="list" + option.json="on") { + constant(value="{") + constant(value="\"timestamp\":\"") property(name="timereported" dateFormat="rfc3339") + constant(value="\",\"message\":\"") property(name="msg") + constant(value="\",\"host\":\"") property(name="hostname") + constant(value="\",\"severity\":\"") property(name="syslogseverity-text") + constant(value="\",\"facility\":\"") property(name="syslogfacility-text") + constant(value="\",\"syslogtag\":\"") property(name="syslogtag") + constant(value="\"}") + } + action(type="omelasticsearch" + server="myserver.local" + serverport="9200" + template="testTemplate" + searchIndex="test-index" + searchType="test-type" + bulkmode="on" + maxbytes="100m" + queue.type="linkedlist" + queue.size="5000" + queue.dequeuebatchsize="300" + action.resumeretrycount="-1") + + +.. _omelasticsearch-writeoperation-example: + +Example 4 +--------- + +The following sample shows how to use :ref:`omelasticsearch-writeoperation` +with :ref:`omelasticsearch-dynbulkid` and :ref:`omelasticsearch-bulkid`. For +simplicity, it assumes rsyslog has been built with `--enable-libuuid` which +provides the `uuid` property for each record: + +.. code-block:: none + + module(load="omelasticsearch") + set $!es_record_id = $uuid; + template(name="bulkid-template" type="list") { property(name="$!es_record_id") } + action(type="omelasticsearch" + ... + bulkmode="on" + bulkid="bulkid-template" + dynbulkid="on" + writeoperation="create") + + +.. _omelasticsearch-retry-example: + +Example 5 +--------- + +The following sample shows how to use :ref:`omelasticsearch-retryfailures` to +process, discard, or retry failed operations. This uses +`writeoperation="create"` with a unique `bulkid` so that we can check for and +discard duplicate messages as successful. The `try_es` ruleset is used both +for the initial attempt and any subsequent retries. The code in the ruleset +assumes that if `$.omes!status` is set and is non-zero, this is a retry for a +previously failed operation. If the status was successful, or Elasticsearch +said this was a duplicate, the record is already in Elasticsearch, so we can +drop the record. If there was some error processing the response +e.g. Elasticsearch sent a response formatted in some way that we did not know +how to process, then submit the record to the `error_es` ruleset. If the +response was a "hard" error like `400`, then submit the record to the +`error_es` ruleset. In any other case, such as a status `429` or `5xx`, the +record will be resubmitted to Elasticsearch. In the example, the `error_es` +ruleset just dumps the records to a file. + +.. code-block:: none + + module(load="omelasticsearch") + module(load="omfile") + template(name="bulkid-template" type="list") { property(name="$.es_record_id") } + + ruleset(name="error_es") { + action(type="omfile" template="RSYSLOG_DebugFormat" file="es-bulk-errors.log") + } + + ruleset(name="try_es") { + if strlen($.omes!status) > 0 then { + # retry case + if ($.omes!status == 200) or ($.omes!status == 201) or (($.omes!status == 409) and ($.omes!writeoperation == "create")) then { + stop # successful + } + if ($.omes!writeoperation == "unknown") or (strlen($.omes!error!type) == 0) or (strlen($.omes!error!reason) == 0) then { + call error_es + stop + } + if ($.omes!status == 400) or ($.omes!status < 200) then { + call error_es + stop + } + # else fall through to retry operation + } + if strlen($.omes!_id) > 0 then { + set $.es_record_id = $.omes!_id; + } else { + # NOTE: depends on rsyslog being compiled with --enable-uuid + set $.es_record_id = $uuid; + } + action(type="omelasticsearch" + ... + bulkmode="on" + bulkid="bulkid-template" + dynbulkid="on" + writeoperation="create" + retryfailures="on" + retryruleset="try_es") + } + call try_es diff --git a/source/configuration/modules/omfile.rst b/source/configuration/modules/omfile.rst new file mode 100644 index 0000000..b5d1b22 --- /dev/null +++ b/source/configuration/modules/omfile.rst @@ -0,0 +1,930 @@ +************************** +omfile: File Output Module +************************** + +=========================== =========================================================================== +**Module Name:** **omfile** +**Author:** `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com> +=========================== =========================================================================== + + +Purpose +======= + +The omfile plug-in provides the core functionality of writing messages +to files residing inside the local file system (which may actually be +remote if methods like NFS are used). Both files named with static names +as well files with names based on message content are supported by this +module. + + +Notable Features +================ + +- :ref:`omfile-statistic-counter` + + +Configuration Parameters +======================== + +Omfile is a built-in module that does not need to be loaded. In order to +specify module parameters, use + +.. code-block:: none + + module(load="builtin:omfile" ...parameters...) + + +Note that legacy parameters **do not** affect new-style RainerScript configuration +objects. See :doc:`basic configuration structure doc <../basic_structure>` to +learn about different configuration languages in use by rsyslog. + +.. note:: + + Parameter names are case-insensitive. + + +General Notes +------------- + +As can be seen in the parameters below, owner and groups can be set either by +name or by direct id (uid, gid). While using a name is more convenient, using +the id is more robust. There may be some situations where the OS is not able +to do the name-to-id resolution, and these cases the owner information will be +set to the process default. This seems to be uncommon and depends on the +authentication provider and service start order. In general, using names +is fine. + + +Module Parameters +----------------- + +Template +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "RSYSLOG_FileFormat", "no", "``$ActionFileDefaultTemplate``" + +Set the default template to be used if an action is not configured +to use a specific template. + + +DirCreateMode +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "FileCreateMode", "0700", "no", "``$DirCreateMode``" + +Sets the default dirCreateMode to be used for an action if no +explicit one is specified. + + +FileCreateMode +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "FileCreateMode", "0644", "no", "``$FileCreateMode``" + +Sets the default fileCreateMode to be used for an action if no +explicit one is specified. + + +fileOwner +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "UID", "process user", "no", "``$FileOwner``" + +Sets the default fileOwner to be used for an action if no +explicit one is specified. + + +fileOwnerNum +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "process user", "no", "none" + +Sets the default fileOwnerNum to be used for an action if no +explicit one is specified. + + +fileGroup +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "GID", "process user's primary group", "no", "``$FileGroup``" + +Sets the default fileGroup to be used for an action if no +explicit one is specified. + + +fileGroupNum +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "process user's primary group", "no", "none" + +Sets the default fileGroupNum to be used for an action if no +explicit one is specified. + + +dirOwner +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "UID", "process user", "no", "``$DirOwner``" + +Sets the default dirOwner to be used for an action if no +explicit one is specified. + + +dirOwnerNum +^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "process user", "no", "none" + +Sets the default dirOwnerNum to be used for an action if no +explicit one is specified. + + +dirGroup +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "GID", "process user's primary group", "no", "``$DirGroup``" + +Sets the default dirGroup to be used for an action if no +explicit one is specified. + + +dirGroupNum +^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "process user's primary group", "no", "none" + +Sets the default dirGroupNum to be used for an action if no +explicit one is specified. + + +dynafile.donotsuspend +^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "none" + +This permits SUSPENDing dynafile actions. Traditionally, SUSPEND mode was +never entered for dynafiles as it would have blocked overall processing +flow. Default is not to suspend (and thus block). + + +compression.driver +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "zlib", "no", "none" + +.. versionadded:: 8.2208.0 + +For compressed operation ("zlib mode"), this permits to set the compression +driver to be used. Originally, only zlib was supported and still is the +default. Since 8.2208.0 zstd is also supported. It provides much better +compression ratios and performance, especially with multiple zstd worker +threads enabled. + +Possible values are: +- zlib +- zstd + + +compression.zstd.workers +^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "positive integer", "zlib library default", "no", "none" + +.. versionadded:: 8.2208.0 + +In zstd mode, this enables to configure zstd-internal compression worker threads. +This setting has nothing to do with rsyslog workers. The zstd library provides +an enhanced worker thread pool which permits multithreaed compression of serial +data streams. Rsyslog fully supports this mode for optimal performance. + +Please note that for this parameter to have an effect, the zstd library must +be compiled with multithreading support. As of this writing (2022), this is +**not** the case for many frequently used distros and distro versions. In this +case, you may want to custom install the zstd library with threading enabled. Note +that this does not require a rsyslog rebuild. + + +Action Parameters +----------------- + +Note that **one** of the parameters *file* or *dynaFile* must be specified. This +selects whether a static or dynamic file (name) shall be written to. + + +File +^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +This creates a static file output, always writing into the same file. +If the file already exists, new data is appended to it. Existing +data is not truncated. If the file does not already exist, it is +created. Files are kept open as long as rsyslogd is active. This +conflicts with external log file rotation. In order to close a file +after rotation, send rsyslogd a HUP signal after the file has been +rotated away. Either file or dynaFile can be used, but not both. If both +are given, dynaFile will be used. + + +dynaFile +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +For each message, the file name is generated based on the given +template. Then, this file is opened. As with the *file* property, +data is appended if the file already exists. If the file does not +exist, a new file is created. The template given in "templateName" +is just a regular :doc:`rsyslog template <../templates>`, so all +you have full control over how to format the file name. Either file +or dynaFile can be used, but not both. If both are given, dynaFile +will be used. + +A cache of recent files is kept. Note +that this cache can consume quite some memory (especially if large +buffer sizes are used). Files are kept open as long as they stay +inside the cache. +Files are removed from the cache when a HUP signal is sent, the +*closeTimeout* occurs, or the cache runs out of space, in which case +the least recently used entry is evicted. + + +Template +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "template set via module parameter", "no", "``$ActionFileDefaultTemplate``" + +Sets the template to be used for this action. + + +closeTimeout +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "File: 0 DynaFile: 10", "no", "none" + +.. versionadded:: 8.3.3 + +Specifies after how many minutes of inactivity a file is +automatically closed. Note that this functionality is implemented +based on the +:doc:`janitor process <../../concepts/janitor>`. +See its doc to understand why and how janitor-based times are +approximate. + + +dynaFileCacheSize +^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "10", "no", "``$DynaFileCacheSize``" + +This parameter specifies the maximum size of the cache for +dynamically-generated file names (dynafile= parmeter). +This setting specifies how many open file handles should +be cached. If, for example, the file name is generated with the hostname +in it and you have 100 different hosts, a cache size of 100 would ensure +that files are opened once and then stay open. This can be a great way +to increase performance. If the cache size is lower than the number of +different files, the least recently used one is discarded (and the file +closed). + +Note that this is a per-action value, so if you have +multiple dynafile actions, each of them have their individual caches +(which means the numbers sum up). Ideally, the cache size exactly +matches the need. You can use :doc:`impstats <impstats>` to tune +this value. Note that a too-low cache size can be a very considerable +performance bottleneck. + + +zipLevel +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "``$OMFileZipLevel``" + +If greater than 0, turns on gzip compression of the output file. The +higher the number, the better the compression, but also the more CPU +is required for zipping. + + +veryRobustZip +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +.. versionadded:: 7.3.0 + +If *zipLevel* is greater than 0, +then this setting controls if extra headers are written to make the +resulting file extra hardened against malfunction. If set to off, +data appended to previously unclean closed files may not be +accessible without extra tools (like `gztool <https://github.com/circulosmeos/gztool>`_ with: ``gztool -p``). +Note that this risk is usually +expected to be bearable, and thus "off" is the default mode. The +extra headers considerably degrade compression, files with this +option set to "on" may be four to five times as large as files +processed in "off" mode. + +**In order to avoid this degradation in compression** both +*flushOnTXEnd* and *asyncWriting* parameters must be set to "off" +and also *ioBufferSize* must be raised from default "4k" value to +at least "32k". This way a reasonable compression factor is +maintained, similar to a non-blocked gzip file: + +.. code-block:: none + + veryRobustZip="on" ioBufferSize="64k" flushOnTXEnd="off" asyncWriting="off" + + +Do not forget to add your desired *zipLevel* to this configuration line. + + +flushInterval +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "1", "no", "``$OMFileFlushInterval``" + +Defines, in seconds, the interval after which unwritten data is +flushed. + + +asyncWriting +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "``$OMFileASyncWriting``" + +If turned on, the files will be written in asynchronous mode via a +separate thread. In that case, double buffers will be used so that +one buffer can be filled while the other buffer is being written. +Note that in order to enable FlushInterval, AsyncWriting must be set +to "on". Otherwise, the flush interval will be ignored. + + +flushOnTXEnd +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "``$OMFileFlushOnTXEnd``" + +Omfile has the capability to write output using a buffered writer. +Disk writes are only done when the buffer is full. So if an error +happens during that write, data is potentially lost. Bear in mind that +the buffer may become full only after several hours or a rsyslog +shutdown (however a buffer flush can still be forced by sending rsyslogd +a HUP signal). In cases where this is unacceptable, set FlushOnTXEnd +to "on". Then, data is written at the end of each transaction +(for pre-v5 this means after each log message) and the usual error +recovery thus can handle write errors without data loss. +Note that this option severely reduces the effect of zip compression +and should be switched to "off" for that use case. +Also note that the default -on- is primarily an aid to preserve the +traditional syslogd behaviour. + +If you are using dynamic file names (dynafiles), flushes can actually +happen more frequently. In this case, a flush can also happen when +the file name changes within a transaction. + + +ioBufferSize +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "size", "4 KiB", "no", "``$OMFileIOBufferSize``" + +Size of the buffer used to writing output data. The larger the +buffer, the potentially better performance is. The default of 4k is +quite conservative, it is useful to go up to 64k, and 128k if you +used gzip compression (then, even higher sizes may make sense) + + +dirOwner +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "UID", "system default", "no", "``$DirOwner``" + +Set the file owner for directories newly created. Please note that +this setting does not affect the owner of directories already +existing. The parameter is a user name, for which the userid is +obtained by rsyslogd during startup processing. Interim changes to +the user mapping are not detected. + + +dirOwnerNum +^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "system default", "no", "``$DirOwnerNum``" + +.. versionadded:: 7.5.8 + +Set the file owner for directories newly created. Please note that +this setting does not affect the owner of directories already +existing. The parameter is a numerical ID, which is used regardless +of whether the user actually exists. This can be useful if the user +mapping is not available to rsyslog during startup. + + +dirGroup +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "GID", "system default", "no", "``$DirGroup``" + +Set the group for directories newly created. Please note that this +setting does not affect the group of directories already existing. +The parameter is a group name, for which the groupid is obtained by +rsyslogd on during startup processing. Interim changes to the user +mapping are not detected. + + +dirGroupNum +^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "system default", "no", "``$DirGroupNum``" + +Set the group for directories newly created. Please note that this +setting does not affect the group of directories already existing. +The parameter is a numerical ID, which is used regardless of whether +the group actually exists. This can be useful if the group mapping is +not available to rsyslog during startup. + + +fileOwner +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "UID", "system default", "no", "``$FileOwner``" + +Set the file owner for files newly created. Please note that this +setting does not affect the owner of files already existing. The +parameter is a user name, for which the userid is obtained by +rsyslogd during startup processing. Interim changes to the user +mapping are *not* detected. + + +fileOwnerNum +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "system default", "no", "``$FileOwnerNum``" + +.. versionadded:: 7.5.8 + +Set the file owner for files newly created. Please note that this +setting does not affect the owner of files already existing. The +parameter is a numerical ID, which which is used regardless of +whether the user actually exists. This can be useful if the user +mapping is not available to rsyslog during startup. + + +fileGroup +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "GID", "system default", "no", "``$FileGroup``" + +Set the group for files newly created. Please note that this setting +does not affect the group of files already existing. The parameter is +a group name, for which the groupid is obtained by rsyslogd during +startup processing. Interim changes to the user mapping are not +detected. + + +fileGroupNum +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "system default", "no", "``$FileGroupNum``" + +.. versionadded:: 7.5.8 + +Set the group for files newly created. Please note that this setting +does not affect the group of files already existing. The parameter is +a numerical ID, which is used regardless of whether the group +actually exists. This can be useful if the group mapping is not +available to rsyslog during startup. + + +fileCreateMode +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "equally-named module parameter", "no", "``$FileCreateMode``" + +The FileCreateMode directive allows to specify the creation mode +with which rsyslogd creates new files. If not specified, the value +0644 is used (which retains backward-compatibility with earlier +releases). The value given must always be a 4-digit octal number, +with the initial digit being zero. +Please note that the actual permission depend on rsyslogd's process +umask. If in doubt, use "$umask 0000" right at the beginning of the +configuration file to remove any restrictions. + + +dirCreateMode +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "equally-named module parameter", "no", "``$DirCreateMode``" + +This is the same as FileCreateMode, but for directories +automatically generated. + + +failOnChOwnFailure +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "``$FailOnCHOwnFailure``" + +This option modifies behaviour of file creation. If different owners +or groups are specified for new files or directories and rsyslogd +fails to set these new owners or groups, it will log an error and NOT +write to the file in question if that option is set to "on". If it is +set to "off", the error will be ignored and processing continues. +Keep in mind, that the files in this case may be (in)accessible by +people who should not have permission. The default is "on". + + +createDirs +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "``$CreateDirs``" + +Create directories on an as-needed basis + + +sync +^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "``$ActionFileEnableSync``" + +Enables file syncing capability of omfile. + +When enabled, rsyslog does a sync to the data file as well as the +directory it resides after processing each batch. There currently +is no way to sync only after each n-th batch. + +Enabling sync causes a severe performance hit. Actually, +it slows omfile so much down, that the probability of loosing messages +**increases**. In short, +you should enable syncing only if you know exactly what you do, and +fully understand how the rest of the engine works, and have tuned +the rest of the engine to lossless operations. + + +sig.Provider +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "no signature provider", "no", "none" + +Selects a signature provider for log signing. By selecting a provider, +the signature feature is turned on. + +Currently there is one signature provider available: ":doc:`ksi_ls12 <sigprov_ksi12>`". + +Previous signature providers ":doc:`gt <sigprov_gt>`" and ":doc:`ksi <sigprov_ksi>`" are deprecated. + + +cry.Provider +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "no crypto provider", "no", "none" + +Selects a crypto provider for log encryption. By selecting a provider, +the encryption feature is turned on. + +Currently, there only is one provider called ":doc:`gcry <../cryprov_gcry>`". + + +rotation.sizeLimit +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "size", "0 (disabled)", "no", "`$outchannel` (partly)" + +This permits to set a size limit on the output file. When the limit is reached, +rotation of the file is tried. The rotation script needs to be configured via +`rotation.sizeLimitCommand`. + +Please note that the size limit is not exact. Some excess bytes are permitted +to prevent messages from being split across two files. Also, a full batch of +messages is not terminated in between. As such, in practice, the size of the +output file can grow some KiB larger than configured. + +Also avoid to configer a too-low limit, especially for busy files. Calling the +rotation script is relatively performance intense. As such, it could negatively +affect overall rsyslog performance. + + +rotation.sizeLimitCommand +^^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "(empty)", "no", "`$outchannel` (partly)" + +This permits to configure the script to be called whe a size limit on the output +file is reached. The actual size limit needs to be configured via +`rotation.sizeLimit`. + + +.. _omfile-statistic-counter: + +Statistic Counter +================= + +This plugin maintains :doc:`statistics <../rsyslog_statistic_counter>` for each +dynafile cache. Dynafile cache performance is critical for overall system performance, +so reviewing these counters on a busy system (especially one experiencing performance +problems) is advisable. The statistic is named "dynafile cache", followed by the +template name used for this dynafile action. + +The following properties are maintained for each dynafile: + +- **request** - total number of requests made to obtain a dynafile + +- **level0** - requests for the current active file, so no real cache + lookup needed to be done. These are extremely good. + +- **missed** - cache misses, where the required file did not reside in + cache. Even with a perfect cache, there will be at least one miss per + file. That happens when the file is being accessed for the first time + and brought into cache. So "missed" will always be at least as large + as the number of different files processed. + +- **evicted** - the number of times a file needed to be evicted from + the cache as it ran out of space. These can simply happen when + date-based files are used, and the previous date files are being + removed from the cache as time progresses. It is better, though, to + set an appropriate "closeTimeout" (counter described below), so that + files are removed from the cache after they become no longer accessed. + It is bad if active files need to be evicted from the cache. This is a + very costly operation as an evict requires to close the file (thus a + full flush, no matter of its buffer state) and a later access requires + a re-open – and the eviction of another file, as the cache obviously has + run out of free entries. If this happens frequently, it can severely + affect performance. So a high eviction rate is a sign that the dynafile + cache size should be increased. If it is already very high, it is + recommended to re-think about the design of the file store, at least if + the eviction process causes real performance problems. + +- **maxused** - the maximum number of cache entries ever used. This can + be used to trim the cache down to a value that’s actually useful but + does not waste resources. Note that when date-based files are used and + rsyslog is run for an extended period of time, the cache gradually fills + up to the max configured value as older files are migrated out of it. + This will make "maxused" questionable after some time. Frequently enough + purging the cache can prevent this (usually, once a day is sufficient). + +- **closetimeouts** - available since 8.3.3 – tells how often a file was + closed due to timeout settings ("closeTimeout" action parameter). These + are cases where dynafiles or static files have been closed by rsyslog due + to inactivity. Note that if no "closeTimeout" is specified for the action, + this counter always is zero. A high or low number in itself doesn’t mean + anything good or bad. It totally depends on the use case, so no general + advise can be given. + + +Caveats/Known Bugs +================== + +- people often report problems that dynafiles are not properly created. + The common cause for this problem is SELinux rules, which do not permit + the create of those files (check generated file names and paths!). The + same happens for generic permission issues (this is often a problem + under Ubuntu where permissions are dropped by default) + +- One needs to be careful with log rotation if signatures and/or + encryption are being used. These create side-files, which form a set + and must be kept together. + For signatures, the ".sigstate" file must NOT be rotated away if + signature chains are to be build across multiple files. This is + because .sigstate contains just global information for the whole file + set. However, all other files need to be rotated together. The proper + sequence is to + + #. move all files inside the file set + #. only AFTER this is completely done, HUP rsyslog + + This sequence will ensure that all files inside the set are + atomically closed and in sync. HUPing only after a subset of files + have been moved results in inconsistencies and will most probably + render the file set unusable. + +- If ``zipLevel`` is greater than 0 and ``veryRobustZip`` is set to off, + data appended to previously unclean closed files will not be + accessible with ``gunzip`` if rsyslog writes again in the same + file. Nonetheless, data is still there and can be correctly accessed + with other tools like `gztool <https://github.com/circulosmeos/gztool>`_ (v>=1.1) with: ``gztool -p``. + + +Examples +======== + +Example 1 +--------- + +The following command writes all syslog messages into a file. + +.. code-block:: none + + action(type="omfile" dirCreateMode="0700" FileCreateMode="0644" + File="/var/log/messages") + + diff --git a/source/configuration/modules/omfwd.rst b/source/configuration/modules/omfwd.rst new file mode 100644 index 0000000..06adcd0 --- /dev/null +++ b/source/configuration/modules/omfwd.rst @@ -0,0 +1,795 @@ +************************************** +omfwd: syslog Forwarding Output Module +************************************** + +=========================== =========================================================================== +**Module Name:** **omfwd** +**Author:** `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com> +=========================== =========================================================================== + + +Purpose +======= + +The omfwd plug-in provides the core functionality of traditional message +forwarding via UDP and plain TCP. It is a built-in module that does not +need to be loaded. + + +Notable Features +================ + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + +Module Parameters +----------------- + +Template +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "RSYSLOG_TraditionalForwardFormat", "no", "``$ActionForwardDefaultTemplateName``" + +Sets a non-standard default template for this module. + + +Action Parameters +----------------- + +Target +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +Name or IP-Address of the system that shall receive messages. Any +resolvable name is fine. + + +Port +^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "514", "no", "none" + +Name or numerical value of port to use when connecting to target. + + +Protocol +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "udp", "no", "none" + +Type of protocol to use for forwarding. Note that \`\`tcp'' means +both legacy plain tcp syslog as well as RFC5425-based TLS-encrypted +syslog. Which one is selected depends on the StreamDriver parameter. +If StreamDriver is set to "ossl" or "gtls" it will use TLS-encrypted syslog. + + +NetworkNamespace +^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +Name of a network namespace as in /var/run/netns/ to use for forwarding. + +If the setns() system call is not available on the system (e.g. BSD +kernel, linux kernel before v2.6.24) the given namespace will be +ignored. + +Address +^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +.. versionadded:: 8.35.0 + +Bind socket to a given local IP address. This option is only supported +for UDP, not TCP. + +IpFreeBind +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "2", "no", "none" + +.. versionadded:: 8.35.0 + +Manages the IP_FREEBIND option on the UDP socket, which allows binding it to +an IP address that is not yet associated to any network interface. This option +is only relevant if the address option is set. + +The parameter accepts the following values: + +- 0 - does not enable the IP_FREEBIND option on the + UDP socket. If the *bind()* call fails because of *EADDRNOTAVAIL* error, + socket initialization fails. + +- 1 - silently enables the IP_FREEBIND socket + option if it is required to successfully bind the socket to a nonlocal address. + +- 2 - enables the IP_FREEBIND socket option and + warns when it is used to successfully bind the socket to a nonlocal address. + +Device +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +Bind socket to given device (e.g., eth0) + +For Linux with VRF support, the Device option can be used to specify the +VRF for the Target address. + + +TCP_Framing +^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "traditional", "no", "none" + +Framing-Mode to be used for forwarding, either "traditional" or +"octet-counted". This affects only TCP-based protocols, it is ignored for UDP. +In protocol engineering, "framing" means how multiple messages over the same +connection are separated. Usually, this is transparent to users. Unfortunately, +the early syslog protocol evolved and so there are cases where users need to +specify the framing. The "traditional" framing is nontransparent. With it, +messages end when an LF (aka "line break", "return") is encountered, and the +next message starts immediately after the LF. If multi-line messages are +received, these are essentially broken up into multiple message, usually with +all but the first message segment being incorrectly formatted. The +"octet-counted" framing solves this issue. With it, each message is prefixed +with the actual message length, so that a receiver knows exactly where the +message ends. Multi-line messages cause no problem here. This mode is very +close to the method described in RFC5425 for TLS-enabled syslog. Unfortunately, +only few syslogd implementations support "octet-counted" framing. As such, the +"traditional" framing is set as default, even though it has defects. If it is +known that the receiver supports "octet-counted" framing, it is suggested to +use that framing mode. + + +TCP_FrameDelimiter +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "10", "no", "none" + +Sets a custom frame delimiter for TCP transmission when running TCP\_Framing +in "traditional" mode. The delimiter has to be a number between 0 and 255 +(representing the ASCII-code of said character). The default value for this +parameter is 10, representing a '\\n'. When using Graylog, the parameter +must be set to 0. + + +ZipLevel +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "none" + +Compression level for messages. + +Up until rsyslog 7.5.1, this was the only compression setting that +rsyslog understood. Starting with 7.5.1, we have different +compression modes. All of them are affected by the ziplevel. If, +however, no mode is explicitly set, setting ziplevel also turns on +"single" compression mode, so pre 7.5.1 configuration will continue +to work as expected. + +The compression level is specified via the usual factor of 0 to 9, +with 9 being the strongest compression (taking up most processing +time) and 0 being no compression at all (taking up no extra +processing time). + + +compression.Mode +^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +*mode* is one of "none", "single", or "stream:always". The default +is "none", in which no compression happens at all. +In "single" compression mode, Rsyslog implements a proprietary +capability to zip transmitted messages. That compression happens on a +message-per-message basis. As such, there is a performance gain only +for larger messages. Before compressing a message, rsyslog checks if +there is some gain by compression. If so, the message is sent +compressed. If not, it is sent uncompressed. As such, it is totally +valid that compressed and uncompressed messages are intermixed within +a conversation. + +In "stream:always" compression mode the full stream is being +compressed. This also uses non-standard protocol and is compatible +only with receives that have the same abilities. This mode offers +potentially very high compression ratios. With typical syslog +messages, it can be as high as 95+% compression (so only one +twentieth of data is actually transmitted!). Note that this mode +introduces extra latency, as data is only sent when the compressor +emits new compressed data. For typical syslog messages, this can mean +that some hundred messages may be held in local buffers before they +are actually sent. This mode has been introduced in 7.5.1. + +**Note: currently only imptcp supports receiving stream-compressed +data.** + + +compression.stream.flushOnTXEnd +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "none" + +.. versionadded:: 7.5.3 + +This setting affects stream compression mode, only. If enabled (the +default), the compression buffer will by emptied at the end of a +rsyslog batch. If set to "off", end of batch will not affect +compression at all. + +While setting it to "off" can potentially greatly improve +compression ratio, it will also introduce severe delay between when a +message is being processed by rsyslog and actually sent out to the +network. We have seen cases where for several thousand message not a +single byte was sent. This is good in the sense that it can happen +only if we have a great compression ratio. This is most probably a +very good mode for busy machines which will process several thousand +messages per second and the resulting short delay will not pose any +problems. However, the default is more conservative, while it works +more "naturally" with even low message traffic. Even in flush mode, +notable compression should be achievable (but we do not yet have +practice reports on actual compression ratios). + + +RebindInterval +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "``$ActionSendTCPRebindInterval`` or ``$ActionSendUDPRebindInterval``" + +Permits to specify an interval at which the current connection is +broken and re-established. This setting is primarily an aid to load +balancers. After the configured number of batches (equals roughly to +messages for UDP traffic, dependent on batch size for TCP) has been +transmitted, the current connection is terminated and a new one +started. Note that this setting applies to both TCP and UDP traffic. +For UDP, the new \`\`connection'' uses a different source port (ports +are cycled and not reused too frequently). This usually is perceived +as a \`\`new connection'' by load balancers, which in turn forward +messages to another physical target system. + + +KeepAlive +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +Enable or disable keep-alive packets at the tcp socket layer. The +default is to disable them. + + +KeepAlive.Probes +^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "none" + +The number of unacknowledged probes to send before considering the +connection dead and notifying the application layer. The default, 0, +means that the operating system defaults are used. This has only +effect if keep-alive is enabled. The functionality may not be +available on all platforms. + + +KeepAlive.Interval +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "none" + +The interval between subsequential keepalive probes, regardless of +what the connection has exchanged in the meantime. The default, 0, +means that the operating system defaults are used. This has only +effect if keep-alive is enabled. The functionality may not be +available on all platforms. + + +KeepAlive.Time +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "none" + +The interval between the last data packet sent (simple ACKs are not +considered data) and the first keepalive probe; after the connection +is marked to need keepalive, this counter is not used any further. +The default, 0, means that the operating system defaults are used. +This has only effect if keep-alive is enabled. The functionality may +not be available on all platforms. + +ConErrSkip +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "none" + +The ConErrSkip can be used to limit the number of network errors +recorded in logs. For example, value 10 means that each 10th error +message is logged. Note that this options should be used as the last +resort since the necessity of its use indicates network issues. +The default behavior is that all network errors are logged. + +RateLimit.Interval +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "max", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "", "no", "none" + +Specifies the rate-limiting interval in seconds. Default value is 0, +which turns off rate limiting. + +RateLimit.Burst +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "max", "mandatory", "none" + :widths: auto + :class: parameter-table + + "integer", "200", "(2^32)-1", "no", "none" + +Specifies the rate-limiting burst in number of messages. + + +StreamDriver +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "``$ActionSendStreamDriver``" + +Choose the stream driver to be used. Default is plain tcp, but +you can also choose "ossl" or "gtls" for TLS encryption. + + +StreamDriverMode +^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "``$ActionSendStreamDriverMode``" + +Mode to use with the stream driver (driver-specific) + + +StreamDriverAuthMode +^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "``$ActionSendStreamDriverAuthMode``" + +Authentication mode to use with the stream driver. Note that this +parameter requires TLS netstream drivers. For all others, it will be +ignored. (driver-specific). + + +StreamDriver.PermitExpiredCerts +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "warn", "no", "none" + +Controls how expired certificates will be handled when stream driver is in TLS mode. +It can have one of the following values: + +- on = Expired certificates are allowed + +- off = Expired certificates are not allowed (Default, changed from warn to off since Version 8.2012.0) + +- warn = Expired certificates are allowed but warning will be logged + + +StreamDriverPermittedPeers +^^^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "``$ActionSendStreamDriverPermittedPeers``" + +Accepted fingerprint (SHA1) or name of remote peer. Note that this +parameter requires TLS netstream drivers. For all others, it will be +ignored. (driver-specific) + + +StreamDriver.CheckExtendedKeyPurpose +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +Whether to check also purpose value in extended fields part of certificate +for compatibility with rsyslog operation. (driver-specific) + + +StreamDriver.PrioritizeSAN +^^^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +Whether to use stricter SAN/CN matching. (driver-specific) + + +StreamDriver.TlsVerifyDepth +^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "TLS library default", "no", "none" + + +Specifies the allowed maximum depth for the certificate chain verification. +Support added in v8.2001.0, supported by GTLS and OpenSSL driver. +If not set, the API default will be used. +For OpenSSL, the default is 100 - see the doc for more: +https://www.openssl.org/docs/man1.1.1/man3/SSL_set_verify_depth.html +For GnuTLS, the default is 5 - see the doc for more: +https://www.gnutls.org/manual/gnutls.html + +StreamDriver.CAFile +^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "global() default", "no", "none" + +.. versionadded:: 8.2108.0 + +This permits to override the CA file set via `global()` config object at the +per-action basis. This parameter is ignored if the netstream driver and/or its +mode does not need or support certificates. + +StreamDriver.CRLFile +^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "optional", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "global() default", "no", "none" + +.. versionadded:: 8.2308.0 + +This permits to override the CRL (Certificate revocation list) file set via `global()` config +object at the per-action basis. This parameter is ignored if the netstream driver and/or its +mode does not need or support certificates. + +StreamDriver.KeyFile +^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "global() default", "no", "none" + +.. versionadded:: 8.2108.0 + +This permits to override the CA file set via `global()` config object at the +per-action basis. This parameter is ignored if the netstream driver and/or its +mode does not need or support certificates. + +StreamDriver.CertFile +^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "global() default", "no", "none" + +.. versionadded:: 8.2108.0 + +This permits to override the CA file set via `global()` config object at the +per-action basis. This parameter is ignored if the netstream driver and/or its +mode does not need or support certificates. + + +ResendLastMSGOnReconnect +^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "``$ActionSendResendLastMsgOnReconnect``" + +Permits to resend the last message when a connection is reconnected. +This setting affects TCP-based syslog, only. It is most useful for +traditional, plain TCP syslog. Using this protocol, it is not always +possible to know which messages were successfully transmitted to the +receiver when a connection breaks. In many cases, the last message +sent is lost. By switching this setting to "yes", rsyslog will always +retransmit the last message when a connection is reestablished. This +reduces potential message loss, but comes at the price that some +messages may be duplicated (what usually is more acceptable). + +Please note that busy systems probably loose more than a +single message in such cases. This is caused by an +`inherant unreliability in plain tcp syslog +<https://rainer.gerhards.net/2008/04/on-unreliability-of-plain-tcp-syslog.html>`_ +and there is no way rsyslog could prevent this from happening +(if you read the detail description, be sure to follow the link +to the follow-up posting). In order to prevent these problems, +we recommend the use of :doc:`omrelp <omrelp>`. + + +udp.SendToAll +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +When sending UDP messages, there are potentially multiple paths to +the target destination. By default, rsyslogd +only sends to the first target it can successfully send to. If this +option is set to "on", messages are sent to all targets. This may improve +reliability, but may also cause message duplication. This option +should be enabled only if it is fully understood. + +Note: this option replaces the former -A command line option. In +contrast to the -A option, this option must be set once per +input() definition. + + +udp.SendDelay +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "none" + +.. versionadded:: 8.7.0 + +This is an **expert option**, do only use it if you know very well +why you are using it! + +This options permits to introduce a small delay after *each* send +operation. The integer specifies the delay in microseconds. This +option can be used in cases where too-quick sending of UDP messages +causes message loss (UDP is permitted to drop packets if e.g. a device +runs out of buffers). Usually, you do not want this delay. The parameter +was introduced in order to support some testbench tests. Be sure +to think twice before you use it in production. + + +gnutlsPriorityString +^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +.. versionadded:: 8.29.0 + +This strings setting is used to configure driver specific properties. +Historically, the setting was only meant for gnutls driver. However +with version v8.1905.0 and higher, the setting can also be used to set openssl configuration commands. + +For GNUTls, the setting specifies the TLS session's handshake algorithms and +options. These strings are intended as a user-specified override of the library +defaults. If this parameter is NULL, the default settings are used. More +information about priority Strings +`here <https://gnutls.org/manual/html_node/Priority-Strings.html>`_. + +For OpenSSL, the setting can be used to pass configuration commands to openssl library. +OpenSSL Version 1.0.2 or higher is required for this feature. +A list of possible commands and their valid values can be found in the documentation: +https://www.openssl.org/docs/man1.0.2/man3/SSL_CONF_cmd.html + +The setting can be single or multiline, each configuration command is separated by linefeed (\n). +Command and value are separated by equal sign (=). Here are a few samples: + +Example 1 +--------- + +This will allow all protocols except for SSLv2 and SSLv3: + +.. code-block:: none + + gnutlsPriorityString="Protocol=ALL,-SSLv2,-SSLv3" + + +Example 2 +--------- + +This will allow all protocols except for SSLv2, SSLv3 and TLSv1. +It will also set the minimum protocol to TLSv1.2 + +.. code-block:: none + + gnutlsPriorityString="Protocol=ALL,-SSLv2,-SSLv3,-TLSv1 + MinProtocol=TLSv1.2" + + +Statistic Counter +================= + +This plugin maintains :doc:`statistics <../rsyslog_statistic_counter>` for each forwarding action. +The statistic is named "target-port-protocol" where "target", "port", and +"protocol" are the respective configuration parameters. So an actual name might be +"192.0.2.1-514-TCP" or "example.net-10514-UDP". + +The following properties are maintained for each action: + +- **bytes.sent** - total number of bytes sent to the network + +See Also +======== + +- `Encrypted Disk + Queues <http://www.rsyslog.com/encrypted-disk-queues/>`_ + + +Examples +======== + +Example 1 +--------- + +The following command sends all syslog messages to a remote server via +TCP port 10514. + +.. code-block:: none + + action(type="omfwd" Target="192.168.2.11" Port="10514" Protocol="tcp" Device="eth0") + + +Example 2 +--------- + +In case the system in use has multiple (maybe virtual) network interfaces network +namespaces come in handy, each with its own routing table. To be able to distribute +syslogs to remote servers in different namespaces specify them as separate actions. + +.. code-block:: none + + action(type="omfwd" Target="192.168.1.13" Port="10514" Protocol="tcp" NetworkNamespace="ns_eth0.0") + action(type="omfwd" Target="192.168.2.24" Port="10514" Protocol="tcp" NetworkNamespace="ns_eth0.1") + action(type="omfwd" Target="192.168.3.38" Port="10514" Protocol="tcp" NetworkNamespace="ns_eth0.2") diff --git a/source/configuration/modules/omhdfs.rst b/source/configuration/modules/omhdfs.rst new file mode 100644 index 0000000..ccdf114 --- /dev/null +++ b/source/configuration/modules/omhdfs.rst @@ -0,0 +1,114 @@ +*************************************** +omhdfs: Hadoop Filesystem Output Module +*************************************** + +=========================== =========================================================================== +**Module Name:** **omhdfs** +**Author:** `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com> +=========================== =========================================================================== + + +Purpose +======= + +This module supports writing message into files on Hadoop's HDFS file +system. + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + + +|FmtObsoleteName| Directives +---------------------------- + +.. csv-table:: + :header: "|FmtObsoleteName| directive", "type", "default", "mandatory" + :widths: auto + :class: parameter-table + + "``$OMHDFSFileName``", "word", "none", "no" + +The name of the file to which the output data shall be written. + +.. csv-table:: + :header: "|FmtObsoleteName| directive", "type", "default", "mandatory" + :widths: auto + :class: parameter-table + + "``$OMHDFSHost``", "word", "default", "no" + +Name or IP address of the HDFS host to connect to. + +.. csv-table:: + :header: "|FmtObsoleteName| directive", "type", "default", "mandatory" + :widths: auto + :class: parameter-table + + "``$OMHDFSPort``", "integer", "0", "no" + +Port on which to connect to the HDFS host. + +.. csv-table:: + :header: "|FmtObsoleteName| directive", "type", "default", "mandatory" + :widths: auto + :class: parameter-table + + "``$OMHDFSDefaultTemplate``", "word", "RSYSLOG_FileFormat", "no" + +Default template to be used when none is specified. This saves the work of +specifying the same template ever and ever again. Of course, the default +template can be overwritten via the usual method. + + +Caveats/Known Bugs +================== + +Building omhdfs is a challenge because we could not yet find out how to +integrate Java properly into the autotools build process. The issue is +that HDFS is written in Java and libhdfs uses JNI to talk to it. That +requires that various system-specific environment options and paths be +set correctly. At this point, we leave this to the user. If someone knows +how to do it better, please drop us a line! + +- In order to build, you need to set these environment variables BEFORE + running ./configure: + + - JAVA\_INCLUDES - must have all include paths that are needed to + build JNI C programs, including the -I options necessary for gcc. + An example is + # export + JAVA\_INCLUDES="-I/usr/lib/jvm/java-1.6.0-openjdk-1.6.0.0.x86\_64/include + -I/usr/lib/jvm/java-1.6.0-openjdk-1.6.0.0.x86\_64/include/linux" + - JAVA\_LIBS - must have all library paths that are needed to build + JNI C programs, including the -l/-L options necessary for gcc. An + example is + # export export + JAVA\_LIBS="-L/usr/java/jdk1.6.0\_21/jre/lib/amd64 + -L/usr/java/jdk1.6.0\_21/jre/lib/amd64/server -ljava -ljvm + -lverify" + +- As of HDFS architecture, you must make sure that all relevant + environment variables (the usual Java stuff and HADOOP's home + directory) are properly set. +- As it looks, libhdfs makes Java throw exceptions to stdout. There is + no known work-around for this (and it usually should not case any + troubles. + + +Examples +======== + +Example 1 +--------- + +.. code-block:: none + + $ModLoad omhdfs + $OMHDFSFileName /var/log/logfile \*.\* :omhdfs: + + diff --git a/source/configuration/modules/omhiredis.rst b/source/configuration/modules/omhiredis.rst new file mode 100644 index 0000000..fb1a98c --- /dev/null +++ b/source/configuration/modules/omhiredis.rst @@ -0,0 +1,779 @@ +****************************** +omhiredis: Redis Output Module +****************************** + +=========================== =========================================================================== +**Module Name:** **omhiredis** +**Author:** Brian Knox <bknox@digitalocean.com> +**Contributors:** Theo Bertin <theo.bertin@advens.fr> +=========================== =========================================================================== + + +Purpose +======= + +This module provides native support for writing to Redis, +using the hiredis client library. + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + + +Action Parameters +----------------- + +Server +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +Name or address of the Redis server + + +ServerPort +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "6379", "no", "none" + +Port of the Redis server if the server is not listening on the default port. + + +ServerPassword +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +Password to support authenticated redis database server to push messages +across networks and datacenters. Parameter is optional if not provided +AUTH command wont be sent to the server. + + +Mode +^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "template", "no", "none" + +Mode to run the output action in: "queue", "publish", "set" or "stream" If not supplied, the +original "template" mode is used. + +.. note:: + + Due to a config parsing bug in 8.13, explicitly setting this to "template" mode will result in a config parsing + error. + + If mode is "set", omhiredis will send SET commands. If "expiration" parameter is provided (see parameter below), + omhiredis will send SETEX commands. + + If mode is "stream", logs will be sent using XADD. In that case, the template-formatted message will be inserted in + the **msg** field of the stream ID (this behaviour can be controlled through the :ref:`omhiredis_streamoutfield` parameter) + +.. _omhiredis_template: + +Template +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "RSYSLOG_ForwardFormat", "no", "none" + +.. Warning:: + Template is required if using "template" mode. + + +Key +^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +Key is required if using "publish", "queue" or "set" modes. + + +Dynakey +^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +If set to "on", the key value will be considered a template by Rsyslog. +Useful when dynamic key generation is desired. + +Userpush +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +If set to on, use RPUSH instead of LPUSH, if not set or off, use LPUSH. + + +Expiration +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "number", "0", "no", "none" + +Only applicable with mode "set". Specifies an expiration for the keys set by omhiredis. +If this parameter is not specified, the value will be 0 so keys will last forever, otherwise they will last for X +seconds. + +.. _omhiredis_streamoutfield: + +stream.outField +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "msg", "no", "none" + +| Only applicable with mode "stream". +| The stream ID's field to use to insert the generated log. + +.. note:: + Currently, the module cannot use the full message object, so it can only insert templated messages to a single stream entry's specific field + + +.. _omhiredis_streamcapacitylimit: + +stream.capacityLimit +^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "positive integer", "0", "no", "none" + +| Only applicable with mode "stream". +| If set to a value greater than 0 (zero), the XADD will add a `MAXLEN <https://redis.io/docs/data-types/streams-tutorial/#capped-streams>`_ option with **approximate** trimming, limiting the amount of stored entries in the stream at each insertion. + +.. Warning:: + This parameter has no way to check if the deleted entries have been ACK'ed once or even used, this should be set if you're sure the insertion rate in lower that the dequeuing to avoid losing entries! + + +.. _omhiredis_streamack: + +stream.ack +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "boolean", "off", "no", "none" + +| Only applicable with mode "stream". +| If set, the module will send an acknowledgement to Redis, for the stream defined by :ref:`omhiredis_streamkeyack`, with the group defined by :ref:`omhiredis_streamgroupack` and the ID defined by :ref:`omhiredis_streamindexack`. +| This is especially useful when used with the :ref:`imhiredis_stream_consumerack` deactivated, as it allows omhiredis to acknowledge the correct processing of the log once the job is effectively done. + + +.. _omhiredis_streamdel: + +stream.del +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "boolean", "off", "no", "none" + +| Only applicable with mode "stream". +| If set, the module will send a XDEL command to remove an entry, for the stream defined by :ref:`omhiredis_streamkeyack`, and the ID defined by :ref:`omhiredis_streamindexack`. +| This can be useful to automatically remove processed entries extracted on a previous stream by imhiredis. + + +.. _omhiredis_streamkeyack: + +stream.keyAck +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "", "no", "none" + +| Only applicable with mode "stream". +| Is **required**, if one of :ref:`omhiredis_streamack` or :ref:`omhiredis_streamdel` are **on**. +| Defines the value to use for acknowledging/deleting while inserting a new entry, can be either a constant value or a template name if :ref:`omhiredis_streamdynakeyack` is set. +| This can be useful to automatically acknowledge/remove processed entries extracted on a previous stream by imhiredis. + + +.. _omhiredis_streamdynakeyack: + +stream.dynaKeyAck +^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "boolean", "off", "no", "none" + +| Only applicable with mode "stream". +| If set to **on**, the value of :ref:`omhiredis_streamkeyack` is taken as an existing Rsyslog template. + + + +.. _omhiredis_streamgroupack: + +stream.groupAck +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "", "no", "none" + +| Only applicable with mode "stream". +| Is **required**, if :ref:`omhiredis_streamack` is **on**. +| Defines the value to use for acknowledging while inserting a new entry, can be either a constant value or a template name if :ref:`omhiredis_streamdynagroupack` is set. +| This can be useful to automatically acknowledge processed entries extracted on a previous stream by imhiredis. + + +.. _omhiredis_streamdynagroupack: + +stream.dynaGroupAck +^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "boolean", "off", "no", "none" + +| Only applicable with mode "stream". +| If set to **on**, the value of :ref:`omhiredis_streamgroupack` is taken as an existing Rsyslog template. + + +.. _omhiredis_streamindexack: + +stream.indexAck +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "", "no", "none" + +| Only applicable with mode "stream". +| Is **required**, if one of :ref:`omhiredis_streamack` or :ref:`omhiredis_streamdel` are **on**. +| Defines the index value to use for acknowledging/deleting while inserting a new entry, can be either a constant value or a template name if :ref:`omhiredis_streamdynaindexack` is set. +| This can be useful to automatically acknowledge/remove processed entries extracted on a previous stream by imhiredis. + + +.. _omhiredis_streamdynaindexack: + +stream.dynaIndexAck +^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "boolean", "off", "no", "none" + +| Only applicable with mode "stream". +| If set to **on**, the value of :ref:`omhiredis_streamindexack` is taken as an existing Rsyslog template. + +Examples +======== + +Example 1: Template mode +------------------------ + +In "template" mode, the string constructed by the template is sent +to Redis as a command. + +.. note:: + + This mode has problems with strings with spaces in them - full message won't work correctly. In this mode, the template argument is required, and the key argument is meaningless. + +.. code-block:: none + + module(load="omhiredis") + + template( + name="program_count_tmpl" + type="string" + string="HINCRBY progcount %programname% 1") + + action( + name="count_programs" + server="my-redis-server.example.com" + serverport="6379" + type="omhiredis" + mode="template" + template="program_count_tmpl") + + +Results +^^^^^^^ + +Here's an example redis-cli session where we HGETALL the counts: + +.. code-block:: none + + > redis-cli + 127.0.0.1:6379> HGETALL progcount + 1) "rsyslogd" + 2) "35" + 3) "rsyslogd-pstats" + 4) "4302" + + +Example 2: Queue mode +--------------------- + +In "queue" mode, the syslog message is pushed into a Redis list +at "key", using the LPUSH command. If a template is not supplied, +the plugin will default to the RSYSLOG_ForwardFormat template. + +.. code-block:: none + + module(load="omhiredis") + + action( + name="push_redis" + server="my-redis-server.example.com" + serverport="6379" + type="omhiredis" + mode="queue" + key="my_queue") + + +Results +^^^^^^^ + +Here's an example redis-cli session where we RPOP from the queue: + +.. code-block:: none + + > redis-cli + 127.0.0.1:6379> RPOP my_queue + + "<46>2015-09-17T10:54:50.080252-04:00 myhost rsyslogd: [origin software=\"rsyslogd\" swVersion=\"8.13.0.master\" x-pid=\"6452\" x-info=\"http://www.rsyslog.com\"] start" + + 127.0.0.1:6379> + + +Example 3: Publish mode +----------------------- + +In "publish" mode, the syslog message is published to a Redis +topic set by "key". If a template is not supplied, the plugin +will default to the RSYSLOG_ForwardFormat template. + +.. code-block:: none + + module(load="omhiredis") + + action( + name="publish_redis" + server="my-redis-server.example.com" + serverport="6379" + type="omhiredis" + mode="publish" + key="my_channel") + + +Results +^^^^^^^ + +Here's an example redis-cli session where we SUBSCRIBE to the topic: + +.. code-block:: none + + > redis-cli + + 127.0.0.1:6379> subscribe my_channel + + Reading messages... (press Ctrl-C to quit) + + 1) "subscribe" + + 2) "my_channel" + + 3) (integer) 1 + + 1) "message" + + 2) "my_channel" + + 3) "<46>2015-09-17T10:55:44.486416-04:00 myhost rsyslogd-pstats: {\"name\":\"imuxsock\",\"origin\":\"imuxsock\",\"submitted\":0,\"ratelimit.discarded\":0,\"ratelimit.numratelimiters\":0}" + + +Example 4: Set mode +------------------- + +In "set" mode, the syslog message is set as a Redis key at "key". If a template is not supplied, +the plugin will default to the RSYSLOG_ForwardFormat template. + +.. code-block:: none + + module(load="omhiredis") + + action( + name="set_redis" + server="my-redis-server.example.com" + serverport="6379" + type="omhiredis" + mode="set" + key="my_key") + + +Results +^^^^^^^ +Here's an example redis-cli session where we get the key: + +.. code-block:: none + + > redis-cli + + 127.0.0.1:6379> get my_key + + "<46>2019-12-17T20:16:54.781239+00:00 localhost rsyslogd-pstats: { \"name\": \"main Q\", \"origin\": \"core.queue\", + \"size\": 3, \"enqueued\": 7, \"full\": 0, \"discarded.full\": 0, \"discarded.nf\": 0, \"maxqsize\": 3 }" + + 127.0.0.1:6379> ttl my_key + + (integer) -1 + + +Example 5: Set mode with expiration +----------------------------------- + +In "set" mode when "expiration" is set to a positive integer, the syslog message is set as a Redis key at "key", +with expiration "expiration". +If a template is not supplied, the plugin will default to the RSYSLOG_ForwardFormat template. + +.. code-block:: none + + module(load="omhiredis") + + action( + name="set_redis" + server="my-redis-server.example.com" + serverport="6379" + type="omhiredis" + mode="set" + key="my_key" + expiration="10") + + +Results +^^^^^^^ + +Here's an example redis-cli session where we get the key and test the expiration: + +.. code-block:: none + + > redis-cli + + 127.0.0.1:6379> get my_key + + "<46>2019-12-17T20:16:54.781239+00:00 localhost rsyslogd-pstats: { \"name\": \"main Q\", \"origin\": \"core.queue\", + \"size\": 3, \"enqueued\": 7, \"full\": 0, \"discarded.full\": 0, \"discarded.nf\": 0, \"maxqsize\": 3 }" + + 127.0.0.1:6379> ttl my_key + + (integer) 10 + + 127.0.0.1:6379> ttl my_key + + (integer) 3 + + 127.0.0.1:6379> ttl my_key + + (integer) -2 + + 127.0.0.1:6379> get my_key + + (nil) + + +Example 6: Set mode with dynamic key +------------------------------------ + +In any mode with "key" defined and "dynakey" as "on", the key used during operation will be dynamically generated +by Rsyslog using templating. + +.. code-block:: none + + module(load="omhiredis") + + template(name="example-template" type="string" string="%hostname%") + + action( + name="set_redis" + server="my-redis-server.example.com" + serverport="6379" + type="omhiredis" + mode="set" + key="example-template" + dynakey="on") + + +Results +^^^^^^^ +Here's an example redis-cli session where we get the dynamic key: + +.. code-block:: none + + > redis-cli + + 127.0.0.1:6379> keys * + + (empty list or set) + + 127.0.0.1:6379> keys * + + 1) "localhost" + + +Example 7: "Simple" stream mode +------------------------------- + +| By using the **stream mode**, the template-formatted log is inserted in a stream using the :ref:`omhiredis_streamoutfield` parameter as key (or *msg* as default). +| The output template can be explicitely set with the :ref:`omhiredis_template` option (or the default *RSYSLOG_ForwardFormat* template will be used). + +.. code-block:: none + + module(load="omhiredis") + + template(name="example-template" type="string" string="%hostname%") + + action( + type="omhiredis" + server="my-redis-server.example.com" + serverport="6379" + template="example-template" + mode="stream" + key="stream_output" + stream.outField="data") + + +Results +^^^^^^^ +Here's an example redis-cli session where we get the newly inserted stream index: + +.. code-block:: none + + > redis-cli + + 127.0.0.1:6379> XLEN stream_output + 1 + + 127.0.0.1:6379> xread STREAMS stream_output 0 + 1) 1) "stream_output" + 2) 1) 1) "1684507855284-0" + 2) 1) "data" + 2) "localhost" + + +Example 8: Get from a stream with imhiredis, then insert in another one with omhiredis +-------------------------------------------------------------------------------------- + +| When you use the omhiredis in stream mode with the imhiredis in stream mode as input, you might want to acknowledge + entries taken with imhiredis once you insert them back somewhere else with omhiredis. +| The module allows to acknowledge input entries using information either provided by the user through configuration + or through information accessible in the log entry. +| Under the hood, imhiredis adds metadata to the generated logs read from redis streams, this data includes + the stream name, ID of the index, group name and consumer name (when read from a consumer group). +| This information is added in the **$.redis** object and can be retrieved with the help of specific templates. + +.. code-block:: none + + module(load="imhiredis") + module(load="omhiredis") + + template(name="redisJsonMessage" type="list") { + property(name="$!output") + } + + template(name="indexTemplate" type="list") { + property(name="$.redis!index") + } + # Not used in this example, but can be used to replace the static declarations in omhiredis' configuration below + template(name="groupTemplate" type="list") { + property(name="$.redis!group") + } + template(name="keyTemplate" type="list") { + property(name="$.redis!stream") + } + + input(type="imhiredis" + server="127.0.0.1" + port="6379" + mode="stream" + key="stream_input" + stream.consumerGroup="group1" + stream.consumerName="consumer1" + stream.consumerACK="off" + ruleset="receive_redis") + + ruleset(name="receive_redis") { + + action(type="omhiredis" + server="127.0.0.1" + serverport="6379" + mode="stream" + key="stream_output" + stream.ack="on" + # The key and group values are set statically, but the index value is taken from imhiredis metadata + stream.dynaKeyAck="off" + stream.keyAck="stream_input" + stream.dynaGroupAck="off" + stream.groupAck="group1" + stream.indexAck="indexTemplate" + stream.dynaIndexAck="on" + template="redisJsonMessage" + ) + } + + +Results +^^^^^^^ +Here's an example redis-cli session where we get the pending entries at the end of the log re-insertion: + +.. code-block:: none + + > redis-cli + + 127.0.0.1:6379> XINFO GROUPS stream_input + 1) 1) "name" + 1) "group1" + 2) "consumers" + 3) (integer) 1 + 4) "pending" + 5) (integer) 0 + 6) "last-delivered-id" + 7) "1684509391900-0" + 8) "entries-read" + 9) (integer) 1 + 10) "lag" + 11) (integer) 0 + + + +Example 9: Ensuring streams don't grow indefinitely +--------------------------------------------------- + +| While using Redis streams, index entries are not automatically evicted, even if you acknowledge entries. +| You have several options to ensure your streams stays under reasonable memoyr usage, while making sure your data is + not evicted before behing processed. +| To do that, you have 2 available options, that can be used independently from each other + (as they don't apply to the same source): + + - **stream.del** to delete processed entries (can also be used as a complement of ACK'ing) + - **stream.capacityLimit** that allows to ensure a hard-limit of logs can be inserted before dropping entries + +.. code-block:: none + + module(load="imhiredis") + module(load="omhiredis") + + template(name="redisJsonMessage" type="list") { + property(name="$!output") + } + + template(name="indexTemplate" type="list") { + property(name="$.redis!index") + } + template(name="keyTemplate" type="list") { + property(name="$.redis!stream") + } + + input(type="imhiredis" + server="127.0.0.1" + port="6379" + mode="stream" + key="stream_input" + ruleset="receive_redis") + + ruleset(name="receive_redis") { + + action(type="omhiredis" + server="127.0.0.1" + serverport="6379" + mode="stream" + key="stream_output" + stream.capacityLimit="1000000" + stream.del="on" + stream.dynaKeyAck="on" + stream.keyAck="keyTemplate" + stream.dynaIndexAck="on" + stream.indexAck="indexTemplate" + template="redisJsonMessage" + ) + } + + +Results +^^^^^^^ +Here, the result of this configuration is: + + - entries are deleted from the source stream *stream_input* after being inserted by omhiredis to *stream_output* + - *stream_output* won't hold more than (approximately) a million entries at a time + +.. Warning:: + The **stream.capacityLimit** is an approximate maximum! see `redis documentation on MAXLEN and the '~' option <https://redis.io/commands/xadd>`_ to understand how it works! diff --git a/source/configuration/modules/omhttp.rst b/source/configuration/modules/omhttp.rst new file mode 100644 index 0000000..3eee0aa --- /dev/null +++ b/source/configuration/modules/omhttp.rst @@ -0,0 +1,869 @@ +******************************************** +omhttp: HTTP Output Module +******************************************** + +=========================== =========================================================================== +**Module Name:** **omhttp** +**Module Type:** **contributed** - not maintained by rsyslog core team +**Current Maintainer:** `Nelson Yen <https://github.com/n2yen/>`_ +Original Author: `Christian Tramnitz <https://github.com/ctramnitz/>`_ +=========================== =========================================================================== + +.. warning:: + + This page is incomplete, if you want to contribute you can do this on + github in the `rsyslog-doc repository <https://github.com/rsyslog/rsyslog-doc>`_. + + + +Purpose +======= + +This module provides the ability to send messages over an HTTP REST interface. + +This module supports sending messages in individual requests (the default), and batching multiple messages into a single request. Support for retrying failed requests is available in both modes. GZIP compression is configurable with the compress_ parameter. TLS encryption is configurable with the useHttps_ parameter and associated tls parameters. + +In the default mode, every message is sent in its own HTTP request and it is a drop-in replacement for any other output module. In batch_ mode, the module implements several batch formatting options that are configurable via the batch.format_ parameter. Some additional attention to message formatting and retry_ strategy is required in this mode. + +See the `Examples`_ section for some configuration examples. + + +Notable Features +================ + +- `Statistic Counter`_ +- `Message Batching`_, supports several formats. + - Newline concatenation, like the Elasticsearch bulk format. + - JSON Array as a generic batching strategy. + - Kafka REST Proxy format, to support sending data through the `Confluent Kafka REST API <https://docs.confluent.io/current/kafka-rest/docs/index.html>`_ to a Kafka cluster. + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + + +Action Parameters +----------------- + +Server +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "array", "localhost", "no", "none" + +The server address you want to connect to. + + +Serverport +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "443", "no", "none" + +The port you want to connect to. + + +healthchecktimeout +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "3500", "no", "none" + +The time after which the health check will time out in milliseconds. + +httpcontenttype +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "application/json; charset=utf-8", "no", "none" + +The HTTP "Content-Type" header sent with each request. This parameter will override other defaults. If a batching mode is specified, the correct content type is automatically configured. The "Content-Type" header can also be configured using the httpheaders_ parameter, it should be configured in only one of the parameters. + + +httpheaderkey +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +The header key. Currently only a single additional header/key pair is configurable, to specify multiple headers see the httpheaders_ parameter. This parameter along with httpheadervalue_ may be deprecated in the future. + + +httpheadervalue +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +The header value for httpheaderkey_. + +httpheaders +^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "array", "none", "no", "none" + +An array of strings that defines a list of one or more HTTP headers to send with each message. Keep in mind that some HTTP headers are added using other parameters, "Content-Type" can be configured using httpcontenttype_ and "Content-Encoding: gzip" is added when using the compress_ parameter. + +.. code-block:: text + + action( + type="omhttp" + ... + httpheaders=[ + "X-Insert-Key: key", + "X-Event-Source: logs" + ] + ... + ) + + +uid +^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +The username for basic auth. + + +pwd +^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +The password for the user for basic auth. + + +restpath +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +The rest path you want to use. Do not include the leading slash character. If the full path looks like "localhost:5000/my/path", restpath should be "my/path". + + +dynrestpath +^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +When this parameter is set to "on" you can specify a template name in the parameter +restpath instead of the actual path. This way you will be able to use dynamic rest +paths for your messages based on the template you are using. + + +checkpath +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +The health check path you want to use. Do not include the leading slash character. If the full path looks like "localhost:5000/my/path", checkpath should be "my/path". +When this parameter is set, omhttp utilizes this path to determine if it is safe to resume (from suspend mode) and communicates this status back to rsyslog core. +This parameter defaults to none, which implies that health checks are not needed, and it is always safe to resume from suspend mode. + +**Important** - Note that it is highly recommended to set a valid health check path, as this allows omhttp to better determine whether it is safe to retry. +See the `rsyslog action queue documentation for more info <https://www.rsyslog.com/doc/v8-stable/configuration/actions.html>`_ regarding general rsyslog suspend and resume behavior. + + +batch +^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +Batch and bulkmode do the same thing, bulkmode included for backwards compatibility. See the `Message Batching`_ section for a detailed breakdown of how batching is implemented. + +This parameter activates batching mode, which queues messages and sends them as a single request. There are several related parameters that specify the format and size of the batch: they are batch.format_, batch.maxbytes_, and batch.maxsize_. + +Note that rsyslog core is the ultimate authority on when a batch must be submitted, due to the way that batching is implemented. This plugin implements the `output plugin transaction interface <https://www.rsyslog.com/doc/v8-stable/development/dev_oplugins.html#output-plugin-transaction-interface>`_. There may be multiple batches in a single transaction, but a batch will never span multiple transactions. This means that if batch.maxsize_ or batch.maxbytes_ is set very large, you may never actually see batches hit this size. Additionally, the number of messages per transaction is determined by the size of the main, action, and ruleset queues as well. + +Additionally, due to some open issues with rsyslog and the transaction interface, batching requires some nuanced retry_ configuration. + + +batch.format +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "newline", "no", "none" + +This parameter specifies how to combine multiple messages into a single batch. Valid options are *newline* (default), *jsonarray*, *kafkarest*, and *lokirest*. + +Each message on the "Inputs" line is the templated log line that is fed into the omhttp action, and the "Output" line describes the resulting payload sent to the configured HTTP server. + +1. *newline* - Concatenates each message into a single string joined by newline ("\\n") characters. This mode is default and places no restrictions on the structure of the input messages. + +.. code-block:: text + + Inputs: "message 1" "message 2" "message 3" + Output: "message 1\nmessage2\nmessage3" + +2. *jsonarray* - Builds a JSON array containing all messages in the batch. This mode requires that each message is parseable JSON, since the plugin parses each message as JSON while building the array. + +.. code-block:: text + + Inputs: {"msg": "message 1"} {"msg"": "message 2"} {"msg": "message 3"} + Output: [{"msg": "message 1"}, {"msg"": "message 2"}, {"msg": "message 3"}] + +3. *kafkarest* - Builds a JSON object that conforms to the `Kafka Rest Proxy specification <https://docs.confluent.io/current/kafka-rest/docs/quickstart.html>`_. This mode requires that each message is parseable JSON, since the plugin parses each message as JSON while building the batch object. + +.. code-block:: text + + Inputs: {"msg": "message 1"} {"msg"": "message 2"} {"msg": "message 3"} + Output: {"records": [{"value": {"msg": "message 1"}}, {"value": {"msg": "message 2"}}, {"value": {"msg": "message 3"}}]} + +4. *lokirest* - Builds a JSON object that conforms to the `Loki Rest specification <https://github.com/grafana/loki/blob/master/docs/api.md#post-lokiapiv1push>`_. This mode requires that each message is parseable JSON, since the plugin parses each message as JSON while building the batch object. Additionally, the operator is responsible for providing index keys, and message values. + +.. code-block:: text + + Inputs: {"stream": {"tag1":"value1"}, values:[[ "%timestamp%", "message 1" ]]} {"stream": {"tag2":"value2"}, values:[[ %timestamp%, "message 2" ]]} + Output: {"streams": [{"stream": {"tag1":"value1"}, values:[[ "%timestamp%", "message 1" ]]},{"stream": {"tag2":"value2"}, values:[[ %timestamp%, "message 2" ]]}]} + +batch.maxsize +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "Size", "100", "no", "none" + +This parameter specifies the maximum number of messages that will be sent in each batch. + +batch.maxbytes +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "Size", "10485760 (10MB)", "no", "none" + +batch.maxbytes and maxbytes do the same thing, maxbytes included for backwards compatibility. + +This parameter specifies the maximum size in bytes for each batch. + +template +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "StdJSONFmt", "no", "none" + +The template to be used for the messages. + +Note that in batching mode, this describes the format of *each* individual message, *not* the format of the resulting batch. Some batch modes require that a template produces valid JSON. + + +retry +^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +This parameter specifies whether failed requests should be retried using the custom retry logic implemented in this plugin. Requests returning 5XX HTTP status codes are considered retriable. If retry is enabled, set retry.ruleset_ as well. + +Note that retries are generally handled in rsyslog by setting action.resumeRetryCount="-1" (or some other integer), and the plugin lets rsyslog know it should start retrying by suspending itself. This is still the recommended approach in the 2 cases enumerated below when using this plugin. In both of these cases, the output plugin transaction interface is not used. That is, from rsyslog core's point of view, each message is contained in its own transaction. + +1. Batching is off (batch="off") +2. Batching is on and the maximum batch size is 1 (batch="on" batch.maxsize="1") + +This custom retry behavior is the result of a bug in rsyslog's handling of transaction commits. See `this issue <https://github.com/rsyslog/rsyslog/issues/2420>`_ for full details. Essentially, if rsyslog hands omhttp 4 messages, and omhttp batches them up but the request fails, rsyslog will only retry the LAST message that it handed the plugin, instead of all 4, even if the plugin returns the correct "defer commit" statuses for messages 1, 2, and 3. This means that omhttp cannot rely on action.resumeRetryCount for any transaction that processes more than a single message, and explains why the 2 above cases do work correctly. + +It looks promising that issue will be resolved at some point, so this behavior can be revisited at that time. + +retry.ruleset +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +This parameter specifies the ruleset where this plugin should requeue failed messages if retry_ is on. This ruleset generally would contain another omhttp action instance. + +**Important** - Note that the message that is queued on the retry ruleset is the templated output of the initial omhttp action. This means that no further templating should be done to messages inside this ruleset, unless retries should be templated differently than first-tries. An "echo template" does the trick here. + +.. code-block:: text + + template(name="tpl_echo" type="string" string="%msg%") + +This retry ruleset can recursively call itself as its own retry.ruleset to retry forever, but there is no timeout behavior currently implemented. + +Alternatively, the omhttp action in the retry ruleset could be configured to support action.resumeRetryCount as explained above in the retry parameter section. The benefit of this approach is that retried messages still hit the server in a batch format (though with a single message in it), and the ability to configure rsyslog to give up after some number of resume attempts so as to avoid resource exhaustion. + +Or, if some data loss or high latency is acceptable, do not configure retries with the retry ruleset itself. A single retry from the original ruleset might catch most failures, and errors from the retry ruleset could still be logged using the errorfile parameter and sent later on via some other process. + +ratelimit.interval +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "600", "no", "none" + +This parameter sets the rate limiting behavior for the retry.ruleset_. Specifies the interval in seconds onto which rate-limiting is to be applied. If more than ratelimit.burst messages are read during that interval, further messages up to the end of the interval are discarded. The number of messages discarded is emitted at the end of the interval (if there were any discards). Setting this to value zero turns off ratelimiting. + +ratelimit.burst +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "20000", "no", "none" + +This parameter sets the rate limiting behavior for the retry.ruleset_. Specifies the maximum number of messages that can be emitted within the ratelimit.interval interval. For further information, see description there. + + +errorfile +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +Here you can set the name of a file where all errors will be written to. Any request that returns a 4XX or 5XX HTTP code is recorded in the error file. Each line is JSON formatted with "request" and "response" fields, example pretty-printed below. + +.. code-block:: text + + { + "request": { + "url": "https://url.com:443/path", + "postdata": "mypayload" + }, + "response" : { + "status": 400, + "message": "error string" + } + } + +It is intended that a full replay of failed data is possible by processing this file. + +compress +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +When switched to "on" each message will be compressed as GZIP using zlib's deflate compression algorithm. + +A "Content-Encoding: gzip" HTTP header is added to each request when this feature is used. Set the compress.level_ for fine-grained control. + +compress.level +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "-1", "no", "none" + +Specify the zlib compression level if compress_ is enabled. Check the `zlib manual <https://www.zlib.net/manual.html>`_ for further documentation. + +"-1" is the default value that strikes a balance between best speed and best compression. "0" disables compression. "1" results in the fastest compression. "9" results in the best compression. + +useHttps +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +When switched to "on" you will use https instead of http. + + +tls.cacert +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +This parameter sets the path to the Certificate Authority (CA) bundle. Expects .pem format. + +tls.mycert +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +This parameter sets the path to the SSL client certificate. Expects .pem format. + +tls.myprivkey +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +The parameters sets the path to the SSL private key. Expects .pem format. + +allowunsignedcerts +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "boolean", "off", "no", "none" + +If `"on"`, this will set the curl `CURLOPT_SSL_VERIFYPEER` option to +`0`. You are strongly discouraged to set this to `"on"`. It is +primarily useful only for debugging or testing. + +skipverifyhost +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "boolean", "off", "no", "none" + +If `"on"`, this will set the curl `CURLOPT_SSL_VERIFYHOST` option to +`0`. You are strongly discouraged to set this to `"on"`. It is +primarily useful only for debugging or testing. + +reloadonhup +^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +If this parameter is "on", the plugin will close and reopen any libcurl handles on a HUP signal. This option is primarily intended to enable reloading short-lived certificates without restarting rsyslog. + +Statistic Counter +================= + +This plugin maintains global :doc:`statistics <../rsyslog_statistic_counter>` for omhttp that +accumulates all action instances. The statistic origin is named "omhttp" with following counters: + +- **messages.submitted** - Number of messages submitted to omhttp. Messages resubmitted via a retry ruleset will be counted twice. + +- **messages.success** - Number of messages successfully sent. + +- **messages.fail** - Number of messages that omhttp failed to deliver for any reason. + +- **messages.retry** - Number of messages that omhttp resubmitted for retry via the retry ruleset. + +- **request.count** - Number of attempted HTTP requests. + +- **request.success** - Number of successful HTTP requests. A successful request can return *any* HTTP status code. + +- **request.fail** - Number of failed HTTP requests. A failed request is something like an invalid SSL handshake, or the server is not reachable. Requests returning 4XX or 5XX HTTP status codes are *not* failures. + +- **request.status.success** - Number of requests returning 1XX or 2XX HTTP status codes. + +- **request.status.fail** - Number of requests returning 3XX, 4XX, or 5XX HTTP status codes. If a requests fails (i.e. server not reachable) this counter will *not* be incremented. + +Message Batching +================ + +See the batch.format_ section for some light examples of available batching formats. + +Implementation +-------------- + +Here's the pseudocode of the batching algorithm used by omhttp. This section of code would run once per transaction. + +.. code-block:: python + + Q = Queue() + + def submit(Q): # function to submit + batch = serialize(Q) # serialize according to configured batch.format + result = post(batch) # http post serialized batch to server + checkFailureAndRetry(Q, result) # check if post failed and pushed failed messages to configured retry.ruleset + Q.empty() # reset for next batch + + + while isActive(transaction): # rsyslog manages the transaction + message = receiveMessage() # rsyslog sends us messages + if wouldTriggerSubmit(Q, message): # if this message puts us over maxbytes or maxsize + submit(Q) # submit the current batch + Q.push(message) # queue this message on the current batch + + submit(Q) # transaction is over, submit what is currently in the queue + + +Walkthrough +----------- + +This is a run through of a file tailing to omhttp scenario. Suppose we have a file called ``/var/log/my.log`` with this content.. + +.. code-block:: text + + 001 message + 002 message + 003 message + 004 message + 005 message + 006 message + 007 message + ... + +We are tailing this using imfile and defining a template to generate a JSON payload... + +.. code-block:: text + + input(type="imfile" File="/var/log/my.log" ruleset="rs_omhttp" ... ) + + # Produces JSON formatted payload + template(name="tpl_omhttp_json" type="list") { + constant(value="{") property(name="msg" outname="message" format="jsonfr") + constant(value=",") property(name="hostname" outname="host" format="jsonfr") + constant(value=",") property(name="timereported" outname="timestamp" format="jsonfr" dateFormat="rfc3339") + constant(value="}") + } + +Our omhttp ruleset is configured to batch using the *jsonarray* format with 5 messages per batch, and to use a retry ruleset. + + +.. code-block:: text + + module(load="omhttp") + + ruleset(name="rs_omhttp") { + action( + type="omhttp" + template="tpl_omhttp_json" + batch="on" + batch.format="jsonarray" + batch.maxsize="5" + retry="on" + retry.ruleset="rs_omhttp_retry" + ... + ) + } + + call rs_omhttp + +Each input message to this omhttp action is the output of ``tpl_omhttp_json`` with the following structure.. + +.. code-block:: text + + {"message": "001 message", "host": "localhost", "timestamp": "2018-12-28T21:14:13.840470+00:00"} + +After 5 messages have been queued, and a batch submit is triggered, omhttp serializes the messages as a JSON array and attempts to post the batch to the server. At this point the payload on the wire looks like this.. + +.. code-block:: text + + [ + {"message": "001 message", "host": "localhost", "timestamp": "2018-12-28T21:14:13.000000+00:00"}, + {"message": "002 message", "host": "localhost", "timestamp": "2018-12-28T21:14:14.000000+00:00"}, + {"message": "003 message", "host": "localhost", "timestamp": "2018-12-28T21:14:15.000000+00:00"}, + {"message": "004 message", "host": "localhost", "timestamp": "2018-12-28T21:14:16.000000+00:00"}, + {"message": "005 message", "host": "localhost", "timestamp": "2018-12-28T21:14:17.000000+00:00"} + ] + +If the request fails, omhttp requeues each failed message onto the retry ruleset. However, recall that the inputs to the ``rs_omhttp`` ruleset are the rendered *outputs* of ``tpl_json_omhttp``, and therefore we *cannot* use the same template (and therefore the same action instance) to produce the retry messages. At this point, the ``msg`` rsyslog property is ``{"message": "001 message", "host": "localhost", "timestamp": "2018-12-28T21:14:13.000000+00:00"}`` instead of the original ``001 message``, and ``tpl_json_omhttp`` would render incorrect payloads. + +Instead we define a simple template that echos its input.. + +.. code-block:: text + + template(name="tpl_echo" type="string" string="%msg%") + +And assign it to the retry template.. + +.. code-block:: text + + ruleset(name="rs_omhttp_retry") { + action( + type="omhttp" + template="tpl_echo" + batch="on" + batch.format="jsonarray" + batch.maxsize="5" + ... + ) + } + +And the destination is none the wiser! The *newline*, *jsonarray*, and *kafkarest* formats all behave in the same way with respect to their batching and retry behavior, and differ only in the format of the on-the-wire payload. The formats themselves are described in the batch.format_ section. + +Examples +======== + +Example 1 +--------- + +The following example is a basic usage, first the module is loaded and then +the action is used with a standard retry strategy. + + +.. code-block:: text + + module(load="omhttp") + template(name="tpl1" type="string" string="{\"type\":\"syslog\", \"host\":\"%HOSTNAME%\"}") + action( + type="omhttp" + server="127.0.0.1" + serverport="8080" + restpath="events" + template="tpl1" + action.resumeRetryCount="3" + ) + +Example 2 +--------- + +The following example is a basic batch usage with no retry processing. + + +.. code-block:: text + + module(load="omhttp") + template(name="tpl1" type="string" string="{\"type\":\"syslog\", \"host\":\"%HOSTNAME%\"}") + action( + type="omhttp" + server="127.0.0.1" + serverport="8080" + restpath="events" + template="tpl1" + batch="on" + batch.format="jsonarray" + batch.maxsize="10" + ) + + +Example 3 +--------- + +The following example is a batch usage with a retry ruleset that retries forever + + +.. code-block:: text + + module(load="omhttp") + + template(name="tpl_echo" type="string" string="%msg%") + ruleset(name="rs_retry_forever") { + action( + type="omhttp" + server="127.0.0.1" + serverport="8080" + restpath="events" + template="tpl_echo" + + batch="on" + batch.format="jsonarray" + batch.maxsize="10" + + retry="on" + retry.ruleset="rs_retry_forever" + ) + } + + template(name="tpl1" type="string" string="{\"type\":\"syslog\", \"host\":\"%HOSTNAME%\"}") + action( + type="omhttp" + server="127.0.0.1" + serverport="8080" + restpath="events" + template="tpl1" + + batch="on" + batch.format="jsonarray" + batch.maxsize="10" + + retry="on" + retry.ruleset="rs_retry_forever" + ) + +Example 4 +--------- + +The following example is a batch usage with a couple retry options + +.. code-block:: text + + module(load="omhttp") + + template(name="tpl_echo" type="string" string="%msg%") + + # This retry ruleset tries to send batches once then logs failures. + # Error log could be tailed by rsyslog itself or processed by some + # other program. + ruleset(name="rs_retry_once_errorfile") { + action( + type="omhttp" + server="127.0.0.1" + serverport="8080" + restpath="events" + template="tpl_echo" + + batch="on" + batch.format="jsonarray" + batch.maxsize="10" + + retry="off" + errorfile="/var/log/rsyslog/omhttp_errors.log" + ) + } + + # This retry ruleset gives up trying to batch messages and instead always + # uses a batch size of 1, relying on the suspend/resume mechanism to do + # further retries if needed. + ruleset(name="rs_retry_batchsize_1") { + action( + type="omhttp" + server="127.0.0.1" + serverport="8080" + restpath="events" + template="tpl_echo" + + batch="on" + batch.format="jsonarray" + batch.maxsize="1" + action.resumeRetryCount="-1" + ) + } + + template(name="tpl1" type="string" string="{\"type\":\"syslog\", \"host\":\"%HOSTNAME%\"}") + action( + type="omhttp" + template="tpl1" + + ... + + retry="on" + retry.ruleset="<some_retry_ruleset>" + ) + +Example 5 +--------- + +The following example is a batch action for pushing logs with checking, and queues to Loki. + +.. code-block:: text + + module(load="omhttp") + + template(name="loki" type="string" string="{\"stream\":{\"host\":\"%HOSTNAME%\",\"facility\":\"%syslogfacility-text%\",\"priority\":\"%syslogpriority-text%\",\"syslogtag\":\"%syslogtag%\"},\"values\": [[ \"%timegenerated:::date-unixtimestamp%000000000\", \"%msg%\" ]]}") + + + action( + name="loki" + type="omhttp" + useHttps="off" + server="localhost" + serverport="3100" + checkpath="ready" + + restpath="loki/api/v1/push" + template="loki" + batch.format="lokirest" + batch="on" + batch.maxsize="10" + + queue.size="10000" queue.type="linkedList" + queue.workerthreads="3" + queue.workerthreadMinimumMessages="1000" + queue.timeoutWorkerthreadShutdown="500" + queue.timeoutEnqueue="10000" + ) diff --git a/source/configuration/modules/omhttpfs.rst b/source/configuration/modules/omhttpfs.rst new file mode 100644 index 0000000..acaf369 --- /dev/null +++ b/source/configuration/modules/omhttpfs.rst @@ -0,0 +1,149 @@ +************************************* +omhttpfs: Hadoop HTTPFS Output Module +************************************* + +=========================== =========================================================================== +**Module Name:** **omhttpfs** +**Available Since:** **8.10.0** +**Author:** `sskaje <https://sskaje.me/2014/12/omhttpfs-rsyslog-hdfs-output-plugin/>`_ <sskaje@gmail.com> +=========================== =========================================================================== + + +Purpose +======= + +This module is an alternative to omhdfs via `Hadoop HDFS over HTTP <http://hadoop.apache.org/docs/current/hadoop-hdfs-httpfs/index.html>`_. + + +Dependencies +============ + +* libcurl + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + + +Action Parameters +----------------- + +Host +^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "127.0.0.1", "no", "none" + +HttpFS server host. + + +Port +^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "14000", "no", "none" + +HttpFS server port. + + +User +^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "hdfs", "no", "none" + +HttpFS auth user. + + +https +^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +Turn on if your HttpFS runs on HTTPS. + + +File +^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "yes", "none" + +File to write, or a template name. + + +isDynFile +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +Turn this on if your **file** is a template name. +See examples below. + + +Template +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "RSYSLOG_FileFormat", "no", "none" + +Format your message when writing to **file**. Default: *RSYSLOG_FileFormat* + + +Configure +========= + +.. code-block:: none + + ./configure --enable-omhttpfs + + +Examples +======== + +Example 1 +--------- + +.. code-block:: none + + module(load="omhttpfs") + template(name="hdfs_tmp_file" type="string" string="/tmp/%$YEAR%/test.log") + template(name="hdfs_tmp_filecontent" type="string" string="%$YEAR%-%$MONTH%-%$DAY% %MSG% ==\n") + local4.* action(type="omhttpfs" host="10.1.1.161" port="14000" https="off" file="hdfs_tmp_file" isDynFile="on") + local5.* action(type="omhttpfs" host="10.1.1.161" port="14000" https="off" file="hdfs_tmp_file" isDynFile="on" template="hdfs_tmp_filecontent") + + diff --git a/source/configuration/modules/omjournal.rst b/source/configuration/modules/omjournal.rst new file mode 100644 index 0000000..fd250a4 --- /dev/null +++ b/source/configuration/modules/omjournal.rst @@ -0,0 +1,71 @@ +********************************* +omjournal: Systemd Journal Output +********************************* + +=========================== =========================================================================== +**Module Name:** **omjournal** +**Author:** `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com> +=========================== =========================================================================== + + +Purpose +======= + +This module provides native support for logging to the systemd journal. + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + + +Action Parameters +----------------- + +Template +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +Template to use when submitting messages. + +By default, rsyslog will use the incoming %msg% as the MESSAGE field +of the journald entry, and include the syslog tag and priority. + +You can override the default formatting of the message, and include +custom fields with a template. Complex fields in the template +(eg. json entries) will be added to the journal as json text. Other +fields will be coerced to strings. + +Journald requires that you include a template parameter named MESSAGE. + + +Examples +======== + +Example 1 +--------- + +The following sample writes all syslog messages to the journal with a +custom EVENT_TYPE field. + +.. code-block:: none + + module(load="omjournal") + + template(name="journal" type="list") { + constant(value="Something happened" outname="MESSAGE") + property(name="$!event-type" outname="EVENT_TYPE") + } + + action(type="omjournal" template="journal") + + diff --git a/source/configuration/modules/omkafka.rst b/source/configuration/modules/omkafka.rst new file mode 100644 index 0000000..ece8cd6 --- /dev/null +++ b/source/configuration/modules/omkafka.rst @@ -0,0 +1,478 @@ +****************************** +omkafka: write to Apache Kafka +****************************** + +=========================== =========================================================================== +**Module Name:** **omkafka** +**Author:** `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com> +**Available since:** v8.7.0 +=========================== =========================================================================== + + +Purpose +======= + +The omkafka plug-in implements an Apache Kafka producer, permitting +rsyslog to write data to Kafka. + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + + +Action Parameters +----------------- + +Note that omkafka supports some *Array*-type parameters. While the parameter +name can only be set once, it is possible to set multiple values with that +single parameter. See the :ref:`omkafka-examples-label` section for details. + + +Broker +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "array", "localhost:9092", "no", "none" + +Specifies the broker(s) to use. + + +Topic +^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "yes", "none" + +Specifies the topic to produce to. + + +Key +^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +Kafka key to be used for all messages. + +If a key is provided and partitions.auto="on" is set, then all messages will +be assigned to a partition based on the key. + + +DynaKey +^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive", "Available since" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none", v8.1903 + +If set, the key parameter becomes a template for the key to base the +partitioning on. + + +DynaTopic +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +If set, the topic parameter becomes a template for which topic to +produce messages to. The cache is cleared on HUP. + + +DynaTopic.Cachesize +^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "50", "no", "none" + +If set, defines the number of topics that will be kept in the dynatopic +cache. + + +Partitions.Auto +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +Librdkafka provides an automatic partitioning function that will +automatically distribute the produced messages into all partitions +configured for that topic. + +To use, set partitions.auto="on". This is instead of specifying the +number of partitions on the producer side, where it would be easier +to change the kafka configuration on the cluster for number of +partitions/topic vs on every machine talking to Kafka via rsyslog. + +If no key is set, messages will be distributed randomly across partitions. +This results in a very even load on all partitions, but does not preserve +ordering between the messages. + +If a key is set, a partition will be chosen automatically based on it. All +messages with the same key will be sorted into the same partition, +preserving their ordering. For example, by setting the key to the hostname, +messages from a specific host will be written to one partition and ordered, +but messages from different nodes will be distributed across different +partitions. This distribution is essentially random, but stable. If the +number of different keys is much larger than the number of partitions on the +topic, load will be distributed fairly evenly. + +If set, it will override any other partitioning scheme configured. + + +Partitions.number +^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "none", "no", "none" + +If set, specifies how many partitions exists **and** activates +load-balancing among them. Messages are distributed more or +less evenly between the partitions. Note that the number specified +must be correct. Otherwise, some errors may occur or some partitions +may never receive data. + + +Partitions.useFixed +^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "none", "no", "none" + +If set, specifies the partition to which data is produced. All +data goes to this partition, no other partition is ever involved +for this action. + + +errorFile +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +If set, messages that could not be sent and caused an error +messages are written to the file specified. This file is in JSON +format, with a single record being written for each message in +error. The entry contains the full message, as well as Kafka +error number and reason string. + +The idea behind the error file is that the admin can periodically +run a script that reads the error file and reacts on it. Note that +the error file is kept open from when the first error occurred up +until rsyslog is terminated or received a HUP signal. + + +statsFile +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +If set, the contents of the JSON object containing the full librdkafka +statistics will be written to the file specified. The file will be +updated based on the statistics.interval.ms confparam value, which must +also be set. + + +ConfParam +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "array", "none", "no", "none" + +Permits to specify Kafka options. Rather than offering a myriad of +config settings to match the Kafka parameters, we provide this setting +here as a vehicle to set any Kafka parameter. This has the big advantage +that Kafka parameters that come up in new releases can immediately be used. + +Note that we use librdkafka for the Kafka connection, so the parameters +are actually those that librdkafka supports. As of our understanding, this +is a superset of the native Kafka parameters. + + +TopicConfParam +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "array", "none", "no", "none" + +In essence the same as *confParam*, but for the Kafka topic. + + +Template +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "template set via template module parameter", "no", "none" + +Sets the template to be used for this action. + + +closeTimeout +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "2000", "no", "none" + +Sets the time to wait in ms (milliseconds) for draining messages submitted to kafka-handle +(provided by librdkafka) before closing it. + +The maximum value of closeTimeout used across all omkafka action instances +is used as librdkafka unload-timeout while unloading the module +(for shutdown, for instance). + + +resubmitOnFailure +^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +.. versionadded:: 8.28.0 + +If enabled, failed messages will be resubmit automatically when kafka is able to send +messages again. To prevent message loss, this option should be enabled. + +**Note:** Messages that are rejected by kafka due to exceeding the maximum configured +message size, are automatically dropped. These errors are not retriable. + +KeepFailedMessages +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +If enabled, failed messages will be saved and loaded on shutdown/startup and resend after startup if +the kafka server is able to receive messages again. This setting requires resubmitOnFailure to be enabled as well. + + +failedMsgFile +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +.. versionadded:: 8.28.0 + +Filename where the failed messages should be stored into. +Needs to be set when keepFailedMessages is enabled, otherwise failed messages won't be saved. + + +statsName +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +.. versionadded:: 8.2108.0 + +The name assigned to statistics specific to this action instance. The supported set of +statistics tracked for this action instance are **submitted**, **acked**, **failures**. +See the :ref:`statistics-counter_label` section for more details. + + +.. _statistics-counter_label: + +Statistic Counter +================= + +This plugin maintains global :doc:`statistics <../rsyslog_statistic_counter>` for omkafka that +accumulate all action instances. The statistic origin is named "omafka" with following counters: + +- **submitted** - number of messages submitted to omkafka for processing (with both acknowledged + deliveries to broker as well as failed or re-submitted from omkafka to librdkafka). + +- **maxoutqsize** - high water mark of output queue size. + +- **failures** - number of messages that librdkafka failed to deliver. This number is + broken down into counts of various types of failures. + +- **topicdynacache.skipped** - count of dynamic topic cache lookups that find an existing topic and + skip creating a new one. + +- **topicdynacache.miss** - count of dynamic topic cache lookups that fail to find an existing topic + and end up creating new ones. + +- **topicdynacache.evicted** - count of dynamic topic cache entry evictions. + +- **acked** - count of messages that were acknowledged by kafka broker. Note that + kafka broker provides two levels of delivery acknowledgements depending on topicConfParam: + default (acks=1) implies delivery to the leader only while acks=-1 implies delivery to leader + as well as replication to all brokers. + +- **failures_msg_too_large** - count of messages dropped by librdkafka when it failed to + deliver to the broker because broker considers message to be too large. Note that + omkafka may still resubmit to librdkafka depending on resubmitOnFailure option. + +- **failures_unknown_topic** - count of messages dropped by librdkafka when it failed to + deliver to the broker because broker does not recognize the topic. + +- **failures_queue_full** - count of messages dropped by librdkafka when its queue becomes + full. Note that default size of librdkafka queue is 100,000 messages. + +- **failures_unknown_partition** - count of messages that librdkafka failed to deliver because + broker does not recognize a partition. + +- **failures_other** - count of all of the rest of the failures that do not fall in any of + the above failure categories. + +- **errors_timed_out** - count of messages that librdkafka could not deliver within timeout. These + errors will cause action to be suspended but messages can be retried depending on retry options. + +- **errors_transport** - count of messages that librdkafka could not deliver due to transport errors. + These messages can be retried depending on retry options. + +- **errors_broker_down** - count of messages that librdkafka could not deliver because it thinks that + broker is not accessible. These messages can be retried depending on options. + +- **errors_auth** - count of messages that librdkafka could not deliver due to authentication errors. + These messages can be retried depending on the options. + +- **errors_ssl** - count of messages that librdkafka could not deliver due to ssl errors. + These messages can be retried depending on the options. + +- **errors_other** - count of rest of librdkafka errors. + +- **rtt_avg_usec** - broker round trip time in microseconds averaged over all brokers. It is based + on the statistics callback window specified through statistics.interval.ms parameter to librdkafka. + Average exclude brokers with less than 100 microseconds rtt. + +- **throttle_avg_msec** - broker throttling time in milliseconds averaged over all brokers. This is + also a part of window statistics delivered by librdkakfka. Average excludes brokers with zero throttling time. + +- **int_latency_avg_usec** - internal librdkafka producer queue latency in microseconds averaged other + all brokers. This is also part of window statistics and average excludes brokers with zero internal latency. + +Note that three window statics counters are not safe with multiple clients. When statistics callback is +enabled, for example, by using statics.callback.ms=60000, omkafa will generate an internal log message every +minute for the corresponding omkafka action: + +.. code-block:: none + + 2018-03-31T01:51:59.368491+00:00 app1-1.example.com rsyslogd: statscb_window_stats: + handler_name=collections.rsyslog.core#producer-1 replyq=0 msg_cnt=30 msg_size=37986 msg_max=100000 + msg_size_max=1073741824 rtt_avg_usec=41475 throttle_avg_msec=0 int_latency_avg_usec=2943224 [v8.32.0] + +For multiple actions using statistics callback, there will be one such record for each action after specified +window period. See https://github.com/edenhill/librdkafka/wiki/Statistics for more details on statistics +callback values. + +Examples +======== + +.. _omkafka-examples-label: + +Using Array Type Parameter +-------------------------- + +Set a single value +^^^^^^^^^^^^^^^^^^ + +For example, to select "snappy" compression, you can use: + +.. code-block:: none + + action(type="omkafka" topic="mytopic" confParam="compression.codec=snappy") + + +which is equivalent to: + +.. code-block:: none + + action(type="omkafka" topic="mytopic" confParam=["compression.codec=snappy"]) + + +Set multiple values +^^^^^^^^^^^^^^^^^^^ + +To specify multiple values, just use the bracket notation and create a +comma-delimited list of values as shown here: + +.. code-block:: none + + action(type="omkafka" topic="mytopic" + confParam=["compression.codec=snappy", + "socket.timeout.ms=5", + "socket.keepalive.enable=true"] + ) + + diff --git a/source/configuration/modules/omlibdbi.rst b/source/configuration/modules/omlibdbi.rst new file mode 100644 index 0000000..01d1e95 --- /dev/null +++ b/source/configuration/modules/omlibdbi.rst @@ -0,0 +1,238 @@ +**************************************** +omlibdbi: Generic Database Output Module +**************************************** + +=========================== =========================================================================== +**Module Name:** **omlibdbi** +**Author:** `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com> +=========================== =========================================================================== + + +Purpose +======= + +This modules supports a large number of database systems via +`libdbi <http://libdbi.sourceforge.net/>`_. Libdbi abstracts the +database layer and provides drivers for many systems. Drivers are +available via the +`libdbi-drivers <http://libdbi-drivers.sourceforge.net/>`_ project. As +of this writing, the following drivers are available: + +- `Firebird/Interbase <http://www.firebird.sourceforge.net/>`_ +- `FreeTDS <http://www.freetds.org/>`_ (provides access to `MS SQL + Server <http://www.microsoft.com/sql>`_ and + `Sybase <http://www.sybase.com/products/informationmanagement/adaptiveserverenterprise>`_) +- `MySQL <http://www.mysql.com/>`_ (also supported via the native + `ommysql <ommysql.html>`_ plugin in rsyslog) +- `PostgreSQL <http://www.postgresql.org/>`_\ (also supported via the + native `ommysql <ommysql.html>`_ plugin in rsyslog) +- `SQLite/SQLite3 <http://www.sqlite.org/>`_ + +The following drivers are in various stages of completion: + +- `Ingres <http://ingres.com/>`_ +- `mSQL <http://www.hughes.com.au/>`_ +- `Oracle <http://www.oracle.com/>`_ + +These drivers seem to be quite usable, at least from an rsyslog point of +view. + +Libdbi provides a slim layer between rsyslog and the actual database +engine. We have not yet done any performance testing (e.g. omlibdbi vs. +:doc:`ommysql`) but honestly believe that the performance impact should be +irrelevant, if at all measurable. Part of that assumption is that +rsyslog just does the "insert" and most of the time is spent either in +the database engine or rsyslog itself. It's hard to think of any +considerable time spent in the libdbi abstraction layer. + + +Setup +===== + +In order for this plugin to work, you need to have libdbi, the libdbi +driver for your database backend and the client software for your +database backend installed. There are libdbi packages for many +distributions. Please note that rsyslogd requires a quite recent version +(0.8.3) of libdbi. It may work with older versions, but these need some +special ./configure options to support being called from a dlopen()ed +plugin (as omlibdbi is). So in short, you probably save you a lot of +headache if you make sure you have at least libdbi version 0.8.3 on your +system. + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + + +Module Parameters +----------------- + +DriverDirectory +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "``$ActionLibdbiDriverDirectory``" + +This is a global setting. It points libdbi to its driver directory. +Usually, you do not need to set it. If you installed libdbi-driver's +at a non-standard location, you may need to specify the directory +here. If you are unsure, do not use this configuration parameter. +Usually, everything works just fine. + + +Template +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +Standard template used for the actions. + + +Action Parameters +----------------- + +Driver +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "yes", "``$ActionLibdbiDriver``" + +Name of the dbidriver to use, see libdbi-drivers documentation. As a +quick excerpt, at least those were available at the time of this +writing: + +- ``mysql`` (:doc:`ommysql` is recommended instead) +- ``firebird`` (Firebird and InterBase) +- ``ingres`` +- ``msql`` +- ``Oracle`` +- ``sqlite`` +- ``sqlite3`` +- ``freetds`` (for Microsoft SQL and Sybase) +- ``pgsql`` (:doc:`ompgsql` is recommended instead) + + +Server +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "yes", "``$ActionLibdbiHost``" + +The host to connect to. + + +UID +^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "yes", "``$ActionLibdbiUserName``" + +The user used to connect to the database. + + +PWD +^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "yes", "``$ActionlibdbiPassword``" + +That user's password. + + +DB +^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "yes", "``$ActionlibdbiDBName``" + +The database that shall be written to. + + +Template +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +Template used for this action. + + +Caveats/Known Bugs: +=================== + +You must make sure that any templates used for omlibdbi properly escape +strings. This is usually done by supplying the SQL (or STDSQL) option to +the template. Omlibdbi rejects templates without this option for +security reasons. However, omlibdbi does not detect if you used the +right option for your backend. Future versions of rsyslog (with +full expression support) will provide advanced ways of handling this +situation. So far, you must be careful. The default template provided by +rsyslog is suitable for MySQL, but not necessarily for your database +backend. Be careful! + +If you receive the rsyslog error message "libdbi or libdbi drivers not +present on this system" you may either not have libdbi and its drivers +installed or (very probably) the version is earlier than 0.8.3. In this +case, you need to make sure you have at least 0.8.3 and the libdbi +driver for your database backend present on your system. + +I do not have most of the database supported by omlibdbi in my lab. So +it received limited cross-platform tests. If you run into troubles, be +sure the let us know at +`http://www.rsyslog.com <http://www.rsyslog.com>`_. + + +Examples +======== + +Example 1 +--------- + +The following sample writes all syslog messages to the database +"syslog_db" on mysqlserver.example.com. The server is MySQL and being +accessed under the account of "user" with password "pwd". + +.. code-block:: none + + module(load="omlibdbi") + action(type="omlibdbi" driver="mysql" server="mysqlserver.example.com" + uid="user" pwd="pwd" db="syslog_db") + + diff --git a/source/configuration/modules/ommail.rst b/source/configuration/modules/ommail.rst new file mode 100644 index 0000000..e28cd17 --- /dev/null +++ b/source/configuration/modules/ommail.rst @@ -0,0 +1,306 @@ +************************** +ommail: Mail Output Module +************************** + +.. index:: ! imudp + +=========================== =========================================================================== +**Module Name:** **ommail** +**Available Since:** **3.17.0** +**Author:** `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com> +=========================== =========================================================================== + + +Purpose +======= + +This module supports sending syslog messages via mail. Each syslog +message is sent via its own mail. Obviously, you will want to apply +rigorous filtering, otherwise your mailbox (and mail server) will be +heavily spammed. The ommail plugin is primarily meant for alerting +users. As such, it is assumed that mails will only be sent in an +extremely limited number of cases. + +Ommail uses up to two templates, one for the mail body and optionally +one for the subject line. Note that the subject line can also be set to +a constant text. +If neither the subject nor the mail body is provided, a quite meaningless +subject line is used +and the mail body will be a syslog message just as if it were written to +a file. It is expected that the users customizes both messages. In an +effort to support cell phones (including SMS gateways), there is an +option to turn off the body part at all. This is considered to be useful +to send a short alert to a pager-like device. +It is highly recommended to use the + +.. code-block:: none + + action.execonlyonceeveryinterval="<seconds>" + +parameter to limit the amount of mails that potentially be +generated. With it, mails are sent at most in a <seconds> interval. This +may be your life safer. And remember that an hour has 3,600 seconds, so +if you would like to receive mails at most once every two hours, include +a + +.. code-block:: none + + action.execonlyonceeveryinterval="7200" + +in the action definition. Messages sent more frequently are simply discarded. + + +Configuration Parameters +======================== + +Configuration parameters are supported starting with v8.5.0. Earlier +v7 and v8 versions did only support legacy parameters. + +.. note:: + + Parameter names are case-insensitive. + + +Action Parameters +----------------- + +Server +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "yes", "``$ActionMailSMTPServer``" + +Name or IP address of the SMTP server to be used. Must currently be +set. The default is 127.0.0.1, the SMTP server on the local machine. +Obviously it is not good to expect one to be present on each machine, +so this value should be specified. + + +Port +^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "yes", "``$ActionMailSMTPPort``" + +Port number or name of the SMTP port to be used. The default is 25, +the standard SMTP port. + + +MailFrom +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "yes", "``$ActionMailFrom``" + +The email address used as the senders address. + + +MailTo +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "array", "none", "yes", "``$ActionMailTo``" + +The recipient email address(es). Note that this is an array parameter. See +samples below on how to specify multiple recipients. + + +Subject.Template +^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "``$ActionMailSubject``" + +The name of the template to be used as the mail subject. + +If you want to include some information from the message inside the +template, you need to use *subject.template* with an appropriate template. +If you just need a constant text, you can simply use *subject.text* +instead, which doesn't require a template definition. + + +Subject.Text +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +This is used to set a **constant** subject text. + + +Body.Enable +^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "``$ActionMailEnableBody``" + +Setting this to "off" permits to exclude the actual message body. +This may be useful for pager-like devices or cell phone SMS messages. +The default is "on", which is appropriate for almost all cases. Turn +it off only if you know exactly what you do! + + +Template +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "RSYSLOG_FileFormat", "no", "none" + +Template to be used for the mail body (if enabled). + +The *template.subject* and *template.text* parameters cannot be given together +inside a single action definition. Use either one of them. If none is used, +a more or less meaningless mail subject is generated (we don't tell you the exact +text because that can change - if you want to have something specific, configure it!). + + +Caveats/Known Bugs +================== + +The current ommail implementation supports SMTP-direct mode only. In +that mode, the plugin talks to the mail server via SMTP protocol. No +other process is involved. This mode offers best reliability as it is +not depending on any external entity except the mail server. Mail server +downtime is acceptable if the action is put onto its own action queue, +so that it may wait for the SMTP server to come back online. However, +the module implements only the bare SMTP essentials. Most importantly, +it does not provide any authentication capabilities. So your mail server +must be configured to accept incoming mail from ommail without any +authentication needs (this may be change in the future as need arises, +but you may also be referred to sendmail-mode). + +In theory, ommail should also offer a mode where it uses the sendmail +utility to send its mail (sendmail-mode). This is somewhat less reliable +(because we depend on an entity we do not have close control over - +sendmail). It also requires dramatically more system resources, as we +need to load the external process (but that should be no problem given +the expected infrequent number of calls into this plugin). The big +advantage of sendmail mode is that it supports all the bells and +whistles of a full-blown SMTP implementation and may even work for local +delivery without a SMTP server being present. Sendmail mode will be +implemented as need arises. So if you need it, please drop us a line (If +nobody does, sendmail mode will probably never be implemented). + + +Examples +======== + +Example 1 +--------- + +The following example alerts the operator if the string "hard disk fatal +failure" is present inside a syslog message. The mail server at +mail.example.net is used and the subject shall be "disk problem on +<hostname>". Note how \\r\\n is included inside the body text to create +line breaks. A message is sent at most once every 6 hours (21600 seconds), +any other messages are silently discarded (or, to be precise, not being +forwarded - they are still being processed by the rest of the configuration +file). + +.. code-block:: none + + module(load="ommail") + + template (name="mailBody" type="string" string="RSYSLOG Alert\\r\\nmsg='%msg%'") + template (name="mailSubject" type="string" string="disk problem on %hostname%") + + if $msg contains "hard disk fatal failure" then { + action(type="ommail" server="mail.example.net" port="25" + mailfrom="rsyslog@example.net" + mailto="operator@example.net" + subject.template="mailSubject" + action.execonlyonceeveryinterval="21600") + } + + +Example 2 +--------- + +The following example is exactly like the first one, but it sends the mails +to two different email addresses: + +.. code-block:: none + + module(load="ommail") + + template (name="mailBody" type="string" string="RSYSLOG Alert\\r\\nmsg='%msg%'") + template (name="mailSubject" type="string" string="disk problem on %hostname%") + + if $msg contains "hard disk fatal failure" then { + action(type="ommail" server="mail.example.net" port="25" + mailfrom="rsyslog@example.net" + mailto=["operator@example.net", "admin@example.net"] + subject.template="mailSubject" + action.execonlyonceeveryinterval="21600") + } + + +Example 3 +--------- + +Note the array syntax to specify email addresses. Note that while rsyslog +permits you to specify as many recipients as you like, your mail server +may limit their number. It is usually a bad idea to use more than 50 +recipients, and some servers may have lower limits. If you hit such a limit, +you could either create additional actions or (recommended) create an +email distribution list. + +The next example is again mostly equivalent to the previous one, but it uses a +constant subject line, so no subject template is required: + +.. code-block:: none + + module(load="ommail") + + template (name="mailBody" type="string" string="RSYSLOG Alert\\r\\nmsg='%msg%'") + + if $msg contains "hard disk fatal failure" then { + action(type="ommail" server="mail.example.net" port="25" + mailfrom="rsyslog@example.net" + mailto=["operator@example.net", "admin@example.net"] + subject.text="rsyslog detected disk problem" + action.execonlyonceeveryinterval="21600") + } + + +Additional Resources +==================== + +A more advanced example plus a discussion on using the email feature +inside a reliable system can be found in Rainer's blogpost "`Why is +native email capability an advantage for a +syslogd? <http://rgerhards.blogspot.com/2008/04/why-is-native-email-capability.html>`_\ " + + diff --git a/source/configuration/modules/ommongodb.rst b/source/configuration/modules/ommongodb.rst new file mode 100644 index 0000000..f048aa1 --- /dev/null +++ b/source/configuration/modules/ommongodb.rst @@ -0,0 +1,247 @@ +******************************** +ommongodb: MongoDB Output Module +******************************** + +=========================== =========================================================================== +**Module Name:** **ommongodb** +**Author:** `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com> +=========================== =========================================================================== + + +Purpose +======= + +This module provides native support for logging to MongoDB. + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + + +Action Parameters +----------------- + +UriStr +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +MongoDB connexion string, as defined by the MongoDB String URI Format (See: https://docs.mongodb.com/manual/reference/connection-string/). If uristr is defined, following directives will be ignored: server, serverport, uid, pwd. + + +SSL_Cert +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +Absolute path to the X509 certificate you want to use for TLS client authentication. This is optional. + + +SSL_Ca +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +Absolute path to the trusted X509 CA certificate that signed the mongoDB server certificate. This is optional. + + +db +^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "syslog", "no", "none" + +Database to use. + + +Collection +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "log", "no", "none" + +Collection to use. + + +Allowed_Error_Codes +^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "array", "no", "no", "none" + +The list of error codes returned by MongoDB you want ommongodb to ignore. +Please use the following format: allowed_error_codes=["11000","47"]. + + +Template +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "OMSR_TPL_AS_MSG", "no", "none" + +Template to use when submitting messages. + +Note rsyslog contains a canned default template to write to the MongoDB. +It will be used automatically if no other template is specified to be +used. This template is: + +.. code-block:: none + + template(name="BSON" type="string" string="\\"sys\\" : \\"%hostname%\\", + \\"time\\" : \\"%timereported:::rfc3339%\\", \\"time\_rcvd\\" : + \\"%timegenerated:::rfc3339%\\", \\"msg\\" : \\"%msg%\\", + \\"syslog\_fac\\" : \\"%syslogfacility%\\", \\"syslog\_server\\" : + \\"%syslogseverity%\\", \\"syslog\_tag\\" : \\"%syslogtag%\\", + \\"procid\\" : \\"%programname%\\", \\"pid\\" : \\"%procid%\\", + \\"level\\" : \\"%syslogpriority-text%\\"") + + +This creates the BSON document needed for MongoDB if no template is +specified. The default schema is aligned to CEE and project lumberjack. +As such, the field names are standard lumberjack field names, and +**not** `rsyslog property names <property_replacer.html>`_. When +specifying templates, be sure to use rsyslog property names as given in +the table. If you would like to use lumberjack-based field names inside +MongoDB (which probably is useful depending on the use case), you need +to select fields names based on the lumberjack schema. If you just want +to use a subset of the fields, but with lumberjack names, you can look +up the mapping in the default template. For example, the lumberjack +field "level" contains the rsyslog property "syslogpriority-text". + + +Examples +======== + + +Write to Database +----------------- + +The following sample writes all syslog messages to the database "syslog" +and into the collection "log" on mongoserver.example.com. The server is +being accessed under the account of "user" with password "pwd". Please note +that this syntax is deprecated by the "uristr" directive, as shown below. + +.. code-block:: none + + module(load="ommongodb") + action(type="ommongodb" + server="mongoserver.example.com" db="syslog" collection="log" + uid="user" pwd="pwd") + + +Write to mongoDB server with TLS and client authentication +---------------------------------------------------------- + +Another sample that uses the new "uristr" directives to connect to a TLS mongoDB server with TLS and client authentication. + +.. code-block:: none + + module(load="ommongodb") + action(type="ommongodb" + uristr="mongodb://vulture:9091,vulture2:9091/?replicaset=Vulture&ssl=true" + ssl_cert="/var/db/mongodb/mongod.pem" + ssl_ca="/var/db/mongodb/ca.pem" + db="logs" collection="syslog") + + +Deprecated Parameters +===================== + +.. note:: + + While these parameters are still accepted, they should no longer be used for newly created configurations. + + +Action Parameters +----------------- + +Server +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "127.0.0.1", "no", "none" + +Name or address of the MongoDB server. + + +ServerPorted +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "27017", "no", "none" + +Permits to select a non-standard port for the MongoDB server. The +default is 0, which means the system default port is used. There is +no need to specify this parameter unless you know the server is +running on a non-standard listen port. + + +UID +^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +Logon userid used to connect to server. Must have proper permissions. + + +PWD +^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +The user's password. + + diff --git a/source/configuration/modules/ommysql.rst b/source/configuration/modules/ommysql.rst new file mode 100644 index 0000000..12d2787 --- /dev/null +++ b/source/configuration/modules/ommysql.rst @@ -0,0 +1,201 @@ +************************************* +ommysql: MySQL Database Output Module +************************************* + +=========================== =========================================================================== +**Module Name:** **ommysql** +**Author:** Michael Meckelein (Initial Author) / `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com> +=========================== =========================================================================== + + +Purpose +======= + +This module provides native support for logging to MySQL databases. It +offers superior performance over the more generic +`omlibdbi <omlibdbi.html>`_ module. + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + + +Action Parameters +----------------- + +Server +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "yes", "none" + +This is the address of the MySQL-Server. + + +Socket +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +This is the unix socket path of the MySQL-Server. When the server +address is set localhost, the mysql client library connects using +the default unix socket specified at build time. +If you run mysql server and run the unix socket path differently +than the default, you can set the socket path with this option. + + +db +^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "yes", "none" + +This is the name of the database used. + + +UID +^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "yes", "none" + +This is the user who is used. + + +PWD +^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "yes", "none" + +This is the password for the user specified in UID. + + +ServerPort +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "none", "no", "``$ActionOmmysqlServerPort``" + +Permits to select a non-standard port for the MySQL server. The +default is 0, which means the system default port is used. There is +no need to specify this parameter unless you know the server is +running on a non-standard listen port. + + +MySQLConfig.File +^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "``$OmMySQLConfigFile``" + +Permits the selection of an optional MySQL Client Library +configuration file (my.cnf) for extended configuration functionality. +The use of this configuration parameter is necessary only if you have +a non-standard environment or if fine-grained control over the +database connection is desired. + + +MySQLConfig.Section +^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "``$OmMySQLConfigSection``" + +Permits the selection of the section within the configuration file +specified by the **$OmMySQLConfigFile** parameter. +This will likely only be used where the database administrator +provides a single configuration file with multiple profiles. +This configuration parameter is ignored unless **$OmMySQLConfigFile** +is also used in the rsyslog configuration file. +If omitted, the MySQL Client Library default of "client" will be +used. + + +Template +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "StdDBFmt", "no", "none" + +Rsyslog contains a canned default template to write to the MySQL +database. It works on the MonitorWare schema. This template is: + +.. code-block:: none + + $template tpl,"insert into SystemEvents (Message, Facility, FromHost, + Priority, DeviceReportedTime, ReceivedAt, InfoUnitID, SysLogTag) values + ('%msg%', %syslogfacility%, '%HOSTNAME%', %syslogpriority%, + '%timereported:::date-mysql%', '%timegenerated:::date-mysql%', %iut%, + '%syslogtag%')",SQL + + +As you can see, the template is an actual SQL statement. Note the ",SQL" +option: it tells the template processor that the template is used for +SQL processing, thus quote characters are quoted to prevent security +issues. You can not assign a template without ",SQL" to a MySQL output +action. + +If you would like to change fields contents or add or delete your own +fields, you can simply do so by modifying the schema (if required) and +creating your own custom template. + + +Examples +======== + +Example 1 +--------- + +The following sample writes all syslog messages to the database +"syslog_db" on mysqlserver.example.com. The server is being accessed +under the account of "user" with password "pwd". + +.. code-block:: none + + module(load="ommysql") + action(type="ommysql" server="mysqlserver.example.com" serverport="1234" + db="syslog_db" uid="user" pwd="pwd") + + diff --git a/source/configuration/modules/omoracle.rst b/source/configuration/modules/omoracle.rst new file mode 100644 index 0000000..4133eb7 --- /dev/null +++ b/source/configuration/modules/omoracle.rst @@ -0,0 +1,200 @@ +omoracle: Oracle Database Output Module +======================================= + +**Module Name: omoracle** + +**Author:**\ Luis Fernando Muñoz Mejías +<Luis.Fernando.Munoz.Mejias@cern.ch> - this module is currently +orphaned, the original author does no longer support it. + +**Available since:**: 4.3.0, **does not work with recent rsyslog +versions (v7 and up). Use** :doc:`omlibdbi <omlibdbi>` **instead.** +An upgrade to the new interfaces is needed. If you would like +to contribute, please send us a patch or open a github pull request. + +**Status:**: contributed module, not maintained by rsyslog core authors + +**Description**: + +This module provides native support for logging to Oracle databases. It +offers superior performance over the more generic +`omlibdbi <omlibdbi.html>`_ module. It also includes a number of +enhancements, most importantly prepared statements and batching, what +provides a big performance improvement. + +Note that this module is maintained by its original author. If you need +assistance with it, it is suggested to post questions to the `rsyslog +mailing list <http://lists.adiscon.net/mailman/listinfo/rsyslog>`_. + +From the header comments of this module: + +:: + + + This is an output module feeding directly to an Oracle + database. It uses Oracle Call Interface, a propietary module + provided by Oracle. + + Selector lines to be used are of this form: + + :omoracle:;TemplateName + + The module gets its configuration via rsyslog $... directives, + namely: + + $OmoracleDBUser: user name to log in on the database. + + $OmoracleDBPassword: password to log in on the database. + + $OmoracleDB: connection string (an Oracle easy connect or a db + name as specified by tnsnames.ora) + + $OmoracleBatchSize: Number of elements to send to the DB on each + transaction. + + $OmoracleStatement: Statement to be prepared and executed in + batches. Please note that Oracle's prepared statements have their + placeholders as ':identifier', and this module uses the colon to + guess how many placeholders there will be. + + All these directives are mandatory. The dbstring can be an Oracle + easystring or a DB name, as present in the tnsnames.ora file. + + The form of the template is just a list of strings you want + inserted to the DB, for instance: + + $template TestStmt,"%hostname%%msg%" + + Will provide the arguments to a statement like + + $OmoracleStatement \ + insert into foo(hostname,message)values(:host,:message) + + Also note that identifiers to placeholders are arbitrary. You + need to define the properties on the template in the correct order + you want them passed to the statement! + +Some additional documentation contributed by Ronny Egner: + +:: + + REQUIREMENTS: + -------------- + + - Oracle Instantclient 10g (NOT 11g) Base + Devel + (if you´re on 64-bit linux you should choose the 64-bit libs!) + - JDK 1.6 (not neccessary for oracle plugin but "make" didd not finsished successfully without it) + + - "oracle-instantclient-config" script + (seems to shipped with instantclient 10g Release 1 but i was unable to find it for 10g Release 2 so here it is) + + + ====================== /usr/local/bin/oracle-instantclient-config ===================== + #!/bin/sh + # + # Oracle InstantClient SDK config file + # Jean-Christophe Duberga - Bordeaux 2 University + # + + # just adapt it to your environment + incdirs="-I/usr/include/oracle/10.2.0.4/client64" + libdirs="-L/usr/lib/oracle/10.2.0.4/client64/lib" + + usage="\ + Usage: oracle-instantclient-config [--prefix[=DIR]] [--exec-prefix[=DIR]] [--version] [--cflags] [--libs] [--static-libs]" + + if test $# -eq 0; then + echo "${usage}" 1>&2 + exit 1 + fi + + while test $# -gt 0; do + case "$1" in + -*=*) optarg=`echo "$1" | sed 's/[-_a-zA-Z0-9]*=//'` ;; + *) optarg= ;; + esac + + case $1 in + --prefix=*) + prefix=$optarg + if test $exec_prefix_set = no ; then + exec_prefix=$optarg + fi + ;; + --prefix) + echo $prefix + ;; + --exec-prefix=*) + exec_prefix=$optarg + exec_prefix_set=yes + ;; + --exec-prefix) + echo ${exec_prefix} + ;; + --version) + echo ${version} + ;; + --cflags) + echo ${incdirs} + ;; + --libs) + echo $libdirs -lclntsh -lnnz10 -locci -lociei -locijdbc10 + ;; + --static-libs) + echo "No static libs" 1>&2 + exit 1 + ;; + *) + echo "${usage}" 1>&2 + exit 1 + ;; + esac + shift + done + + =============== END ============== + + + + + COMPILING RSYSLOGD + ------------------- + + + ./configure --enable-oracle + + + + + RUNNING + ------- + + - make sure rsyslogd is able to locate the oracle libs (either via LD_LIBRARY_PATH or /etc/ld.so.conf) + - set TNS_ADMIN to point to your tnsnames.ora + - create a tnsnames.ora and test you are able to connect to the database + + - create user in oracle as shown in the following example: + create user syslog identified by syslog default tablespace users quota unlimited on users; + grant create session to syslog; + create role syslog_role; + grant syslog_role to syslog; + grant create table to syslog_role; + grant create sequence to syslog_role; + + - create tables as needed + + - configure rsyslog as shown in the following example + $ModLoad omoracle + + $OmoracleDBUser syslog + $OmoracleDBPassword syslog + $OmoracleDB syslog + $OmoracleBatchSize 1 + $OmoracleBatchItemSize 4096 + + $OmoracleStatementTemplate OmoracleStatement + $template OmoracleStatement,"insert into foo(hostname,message) values (:host,:message)" + $template TestStmt,"%hostname%%msg%" + *.* :omoracle:;TestStmt + (you guess it: username = password = database = "syslog".... see $rsyslogd_source/plugins/omoracle/omoracle.c for me info) + diff --git a/source/configuration/modules/ompgsql.rst b/source/configuration/modules/ompgsql.rst new file mode 100644 index 0000000..4df4745 --- /dev/null +++ b/source/configuration/modules/ompgsql.rst @@ -0,0 +1,239 @@ +.. index:: ! ompgsql + +******************************************* +PostgreSQL Database Output Module (ompgsql) +******************************************* + +================ ========================================================================== +**Module Name:** ompgsql +**Author:** `Rainer Gerhards <rgerhards@adiscon.com>`__ and `Dan Molik <dan@danmolik.com>`__ +**Available:** 8.32+ +================ ========================================================================== + + +Purpose +======= + +This module provides native support for logging to PostgreSQL databases. +It's an alternative (with potentially superior performance) to the more +generic :doc:`omlibdbi <omlibdbi>` module. + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + + +Action Parameters +----------------- + +Conninfo +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +The URI or set of key-value pairs that describe how to connect to the PostgreSQL +server. This takes precedence over ``server``, ``port``, ``db``, and ``pass`` +parameters. Required if ``server`` and ``db`` are not specified. + +The format corresponds to `standard PostgreSQL connection string format +<https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNSTRING>`_. + +Server +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +The hostname or address of the PostgreSQL server. Required if ``conninfo`` is +not specified. + + +Port/Serverport +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "5432", "no", "none" + +The IP port of the PostgreSQL server. + + +db +^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +The multi-tenant database name to ``INSERT`` rows into. Required if ``conninfo`` +is not specified. + + +User/UID +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "postgres", "no", "none" + +The username to connect to the PostgreSQL server with. + + +Pass/PWD +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "postgres", "no", "none" + +The password to connect to the PostgreSQL server with. + + +Template +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +The template name to use to ``INSERT`` rows into the database with. Valid SQL +syntax is required, as the module does not perform any insertion statement +checking. + + +Examples +======== + +Example 1 +--------- + +A Basic Example using the internal PostgreSQL template. + +.. code-block:: none + + # load module + module(load="ompgsql") + + action(type="ompgsql" server="localhost" + user="rsyslog" pass="test1234" + db="syslog") + + +Example 2 +--------- + +A Basic Example using the internal PostgreSQL template and connection using URI. + +.. code-block:: none + + # load module + module(load="ompgsql") + + action(type="ompgsql" + conninfo="postgresql://rsyslog:test1234@localhost/syslog") + + +Example 3 +--------- + +A Basic Example using the internal PostgreSQL template and connection with TLS using URI. + +.. code-block:: none + + # load module + module(load="ompgsql") + + action(type="ompgsql" + conninfo="postgresql://rsyslog:test1234@postgres.example.com/syslog?sslmode=verify-full&sslrootcert=/path/to/cert") + + +Example 4 +--------- + +A Templated example. + +.. code-block:: none + + template(name="sql-syslog" type="list" option.stdsql="on") { + constant(value="INSERT INTO SystemEvents (message, timereported) values ('") + property(name="msg") + constant(value="','") + property(name="timereported" dateformat="pgsql" date.inUTC="on") + constant(value="')") + } + + # load module + module(load="ompgsql") + + action(type="ompgsql" server="localhost" + user="rsyslog" pass="test1234" + db="syslog" + template="sql-syslog" ) + + +Example 5 +--------- + +An action queue and templated example. + +.. code-block:: none + + template(name="sql-syslog" type="list" option.stdsql="on") { + constant(value="INSERT INTO SystemEvents (message, timereported) values ('") + property(name="msg") + constant(value="','") + property(name="timereported" dateformat="pgsql" date.inUTC="on") + constant(value="')") + } + + # load module + module(load="ompgsql") + + action(type="ompgsql" server="localhost" + user="rsyslog" pass="test1234" + db="syslog" + template="sql-syslog" + queue.size="10000" queue.type="linkedList" + queue.workerthreads="5" + queue.workerthreadMinimumMessages="500" + queue.timeoutWorkerthreadShutdown="1000" + queue.timeoutEnqueue="10000") + + +Building +======== + +To compile Rsyslog with PostgreSQL support you will need to: + +* install *libpq* and *libpq-dev* packages, check your package manager for the correct name. +* set *--enable-pgsql* switch on configure. + + diff --git a/source/configuration/modules/ompipe.rst b/source/configuration/modules/ompipe.rst new file mode 100644 index 0000000..1bf581e --- /dev/null +++ b/source/configuration/modules/ompipe.rst @@ -0,0 +1,48 @@ +ompipe: Pipe Output Module +========================== + +**Module Name: ompipe** + +**Author:**\ Rainer Gerhards <rgerhards@adiscon.com> + +**Description**: + +The ompipe plug-in provides the core functionality for logging output to named pipes (fifos). It is a built-in module that does not need to be loaded. + +**Global Configuration Parameters:** + +Note: parameter names are case-insensitive. + +- Template: [templateName] sets a new default template for file actions. + +**Action specific Configuration Parameters:** + +Note: parameter names are case-insensitive. + +- Pipe: string a fifo or named pipe can be used as a destination for log messages. +- tryResumeReopen: Sometimes we need to reopen a pipe after an ompipe action gets suspended. Sending an HUP signal does the job but requires an interaction with rsyslog. When set to "on" and a resume action fails, the file descriptor is closed, causing a new open in the next resume. Default: "off" to preserve existing behavior before introduction of this option. + +**Caveats/Known Bugs:** +None + +**Sample:** +The following command sends all syslog messages to a pipe named "NameofPipe". + +:: + + Module (path="builtin:ompipe") + *.* action(type="ompipe" Pipe="NameofPipe") + +**Legacy Configuration Parameters:** + +rsyslog has support for logging output to named pipes (fifos). A fifo or named pipe can be used as a destination for log messages by prepending a pipe symbol ("|") to the name of the file. This is handy for debugging. Note that the fifo must be created with the mkfifo(1) command before rsyslogd is started. + +**Legacy Sample:** + +The following command sends all syslog messages to a pipe named /var/log/pipe. + +:: + + $ModLoad ompipe + *.* |/var/log/pipe + diff --git a/source/configuration/modules/omprog.rst b/source/configuration/modules/omprog.rst new file mode 100644 index 0000000..d96fec1 --- /dev/null +++ b/source/configuration/modules/omprog.rst @@ -0,0 +1,530 @@ +***************************************** +omprog: Program integration Output module +***************************************** + +=========================== =========================================================================== +**Module Name:** **omprog** +**Author:** `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com> +=========================== =========================================================================== + + +Purpose +======= + +This module permits to integrate arbitrary external programs into +rsyslog's logging. It is similar to the "execute program (^)" action, +but offers better security and much higher performance. While "execute +program (^)" can be a useful tool for executing programs if rare events +occur, omprog can be used to provide massive amounts of log data to a +program. + +Executes the configured program and feeds log messages to that binary +via stdin. The binary is free to do whatever it wants with the supplied +data. If the program terminates, it is re-started. If rsyslog +terminates, the program's stdin will see EOF. The program must then +terminate. The message format passed to the program can, as usual, be +modified by defining rsyslog templates. + +Note that in order to execute the given program, rsyslog needs to have +sufficient permissions on the binary file. This is especially true if +not running as root. Also, keep in mind that default SELinux policies +most probably do not permit rsyslogd to execute arbitrary binaries. As +such, permissions must be appropriately added. Note that SELinux +restrictions also apply if rsyslogd runs under root. To check if a +problem is SELinux-related, you can temporarily disable SELinux and +retry. If it then works, you know for sure you have a SELinux issue. + +Starting with 8.4.0, rsyslogd emits an error message via the ``syslog()`` +API call when there is a problem executing the binary. This can be +extremely valuable in troubleshooting. For those technically savvy: +when we execute a binary, we need to fork, and we do not have +full access to rsyslog's usual error-reporting capabilities after the +fork. As the actual execution must happen after the fork, we cannot +use the default error logger to emit the error message. As such, +we use ``syslog()``. In most cases, there is no real difference +between both methods. However, if you run multiple rsyslog instances, +the message shows up in that instance that processes the default +log socket, which may be different from the one where the error occurred. +Also, if you redirected the log destination, that redirection may +not work as expected. + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + + +Action Parameters +----------------- + +template +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "RSYSLOG_FileFormat", "no", "none" + +Name of the :doc:`template <../templates>` to use to format the log messages +passed to the external program. + + +binary +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "", "yes", "``$ActionOMProgBinary``" + +Full path and command line parameters of the external program to execute. +Arbitrary external programs should be placed under the /usr/libexec/rsyslog directory. +That is, the binaries put in this namespaced directory are meant for the consumption +of rsyslog, and are not intended to be executed by users. +In legacy config, it is **not possible** to specify command line parameters. + + +.. _confirmMessages: + +confirmMessages +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +.. versionadded:: 8.31.0 + +Specifies whether the external program provides feedback to rsyslog via stdout. +When this switch is set to "on", rsyslog will wait for the program to confirm +each received message. This feature facilitates error handling: instead of +having to implement a retry logic, the external program can rely on the rsyslog +queueing capabilities. + +To confirm a message, the program must write a line with the word ``OK`` to its +standard output. If it writes a line containing anything else, rsyslog considers +that the message could not be processed, keeps it in the action queue, and +re-sends it to the program later (after the period specified by the +:doc:`action.resumeInterval <../actions>` parameter). + +In addition, when a new instance of the program is started, rsyslog will also +wait for the program to confirm it is ready to start consuming logs. This +prevents rsyslog from starting to send logs to a program that could not +complete its initialization properly. + +.. seealso:: + + `Interface between rsyslog and external output plugins + <https://github.com/rsyslog/rsyslog/blob/master/plugins/external/INTERFACE.md>`_ + + +.. _confirmTimeout: + +confirmTimeout +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "10000", "no", "none" + +.. versionadded:: 8.38.0 + +Specifies how long rsyslog must wait for the external program to confirm +each message when confirmMessages_ is set to "on". If the program does not +send a response within this timeout, it will be restarted (see signalOnClose_, +closeTimeout_ and killUnresponsive_ for details on the cleanup sequence). +The value must be expressed in milliseconds and must be greater than zero. + +.. seealso:: + + `Interface between rsyslog and external output plugins + <https://github.com/rsyslog/rsyslog/blob/master/plugins/external/INTERFACE.md>`_ + + +.. _reportFailures: + +reportFailures +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +.. versionadded:: 8.38.0 + +Specifies whether rsyslog must internally log a warning message whenever the +program returns an error when confirming a message. The logged message will +include the error line returned by the program. This parameter is ignored when +confirmMessages_ is set to "off". + +Enabling this flag can be useful to log the problems detected by the program. +However, the information that can be logged is limited to a short error line, +and the logs will be tagged as originated by the 'syslog' facility (like the +rest of rsyslog logs). To avoid these shortcomings, consider the use of the +output_ parameter to capture the stderr of the program. + + +.. _useTransactions: + +useTransactions +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +.. versionadded:: 8.31.0 + +Specifies whether the external program processes the messages in +:doc:`batches <../../development/dev_oplugins>` (transactions). When this +switch is enabled, the logs sent to the program are grouped in transactions. +At the start of a transaction, rsyslog sends a special mark message to the +program (see beginTransactionMark_). At the end of the transaction, rsyslog +sends another mark message (see commitTransactionMark_). + +If confirmMessages_ is also set to "on", the program must confirm both the +mark messages and the logs within the transaction. The mark messages must be +confirmed by returning ``OK``, and the individual messages by returning +``DEFER_COMMIT`` (instead of ``OK``). Refer to the link below for details. + +.. seealso:: + + `Interface between rsyslog and external output plugins + <https://github.com/rsyslog/rsyslog/blob/master/plugins/external/INTERFACE.md>`_ + +.. warning:: + + This feature is currently **experimental**. It could change in future releases + without keeping backwards compatibility with existing configurations or the + specified interface. There is also a `known issue + <https://github.com/rsyslog/rsyslog/issues/2420>`_ with the use of + transactions together with ``confirmMessages=on``. + + +.. _beginTransactionMark: + +beginTransactionMark +^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "BEGIN TRANSACTION", "no", "none" + +.. versionadded:: 8.31.0 + +Allows specifying the mark message that rsyslog will send to the external +program to indicate the start of a transaction (batch). This parameter is +ignored if useTransactions_ is disabled. + + +.. _commitTransactionMark: + +commitTransactionMark +^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "COMMIT TRANSACTION", "no", "none" + +.. versionadded:: 8.31.0 + +Allows specifying the mark message that rsyslog will send to the external +program to indicate the end of a transaction (batch). This parameter is +ignored if useTransactions_ is disabled. + + +.. _output: + +output +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +.. versionadded:: v8.1.6 + +Full path of a file where the output of the external program will be saved. +If the file already exists, the output is appended to it. If the file does +not exist, it is created with the permissions specified by fileCreateMode_. + +If confirmMessages_ is set to "off" (the default), both the stdout and +stderr of the child process are written to the specified file. + +If confirmMessages_ is set to "on", only the stderr of the child is +written to the specified file (since stdout is used for confirming the +messages). + +Rsyslog will reopen the file whenever it receives a HUP signal. This allows +the file to be externally rotated (using a tool like *logrotate*): after +each rotation of the file, make sure a HUP signal is sent to rsyslogd. + +If the omprog action is configured to use multiple worker threads +(:doc:`queue.workerThreads <../../rainerscript/queue_parameters>` is +set to a value greater than 1), the lines written by the various program +instances will not appear intermingled in the output file, as long as the +lines do not exceed a certain length and the program writes them to +stdout/stderr in line-buffered mode. For details, refer to `Interface between +rsyslog and external output plugins +<https://github.com/rsyslog/rsyslog/blob/master/plugins/external/INTERFACE.md>`_. + +If this parameter is not specified, the output of the program will be +redirected to ``/dev/null``. + +.. note:: + + Before version v8.38.0, this parameter was intended for debugging purposes + only. Since v8.38.0, the parameter can be used for production. + + +.. _fileCreateMode: + +fileCreateMode +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "0600", "no", "none" + +.. versionadded:: v8.38.0 + +Permissions the output_ file will be created with, in case the file does not +exist. The value must be a 4-digit octal number, with the initial digit being +zero. Please note that the actual permission depends on the rsyslogd process +umask. If in doubt, use ``$umask 0000`` right at the beginning of the +configuration file to remove any restrictions. + + +hup.signal +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +.. versionadded:: 8.9.0 + +Specifies which signal, if any, is to be forwarded to the external program +when rsyslog receives a HUP signal. Currently, HUP, USR1, USR2, INT, and +TERM are supported. If unset, no signal is sent on HUP. This is the default +and what pre 8.9.0 versions did. + + +.. _signalOnClose: + +signalOnClose +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +.. versionadded:: 8.23.0 + +Specifies whether a TERM signal must be sent to the external program before +closing it (when either the worker thread has been unscheduled, a restart +of the program is being forced, or rsyslog is about to shutdown). + +If this switch is set to "on", rsyslog will send a TERM signal to the child +process before closing the pipe. That is, the process will first receive a +TERM signal, and then an EOF on stdin. + +No signal is issued if this switch is set to "off" (default). The child +process can still detect it must terminate because reading from stdin will +return EOF. + +See the killUnresponsive_ parameter for more details. + + +.. _closeTimeout: + +closeTimeout +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "5000", "no", "none" + +.. versionadded:: 8.35.0 + +Specifies how long rsyslog must wait for the external program to terminate +(when either the worker thread has been unscheduled, a restart of the program +is being forced, or rsyslog is about to shutdown) after closing the pipe, +that is, after sending EOF to the stdin of the child process. The value must +be expressed in milliseconds and must be greater than or equal to zero. + +See the killUnresponsive_ parameter for more details. + + +.. _killUnresponsive: + +killUnresponsive +^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "the value of 'signalOnClose'", "no", "none" + +.. versionadded:: 8.35.0 + +Specifies whether a KILL signal must be sent to the external program in case +it does not terminate within the timeout indicated by closeTimeout_ +(when either the worker thread has been unscheduled, a restart of the program +is being forced, or rsyslog is about to shutdown). + +If signalOnClose_ is set to "on", the default value of ``killUnresponsive`` +is also "on". In this case, the cleanup sequence of the child process is as +follows: (1) a TERM signal is sent to the child, (2) the pipe with the child +process is closed (the child will receive EOF on stdin), (3) rsyslog waits +for the child process to terminate during closeTimeout_, (4) if the child +has not terminated within the timeout, a KILL signal is sent to it. + +If signalOnClose_ is set to "off", the default value of ``killUnresponsive`` +is also "off". In this case, the child cleanup sequence is as follows: (1) the +pipe with the child process is closed (the child will receive EOF on stdin), +(2) rsyslog waits for the child process to terminate during closeTimeout_, +(3) if the child has not terminated within the timeout, rsyslog ignores it. + +This parameter can be set to a different value than signalOnClose_, obtaining +the corresponding variations of cleanup sequences described above. + + +forceSingleInstance +^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +.. versionadded:: v8.1.6 + +By default, the omprog action will start an instance (process) of the +external program per worker thread (the maximum number of worker threads +can be specified with the +:doc:`queue.workerThreads <../../rainerscript/queue_parameters>` +parameter). Moreover, if the action is associated to a +:doc:`disk-assisted queue <../../concepts/queues>`, an additional instance +will be started when the queue is persisted, to process the items stored +on disk. + +If you want to force a single instance of the program to be executed, +regardless of the number of worker threads or the queue type, set this +flag to "on". This is useful when the external program uses or accesses +some kind of shared resource that does not allow concurrent access from +multiple processes. + +.. note:: + + Before version v8.38.0, this parameter had no effect. + + +Examples +======== + +Example: command line arguments +------------------------------- + +In the following example, logs will be sent to a program ``log.sh`` located +in ``/usr/libexec/rsyslog``. The program will receive the command line arguments +``p1``, ``p2`` and ``--param3="value 3"``. + +.. code-block:: none + + module(load="omprog") + + action(type="omprog" + binary="/usr/libexec/rsyslog/log.sh p1 p2 --param3=\"value 3\"" + template="RSYSLOG_TraditionalFileFormat") + + +Example: external program that writes logs to a database +-------------------------------------------------------- + +In this example, logs are sent to the stdin of a Python program that +(let's assume) writes them to a database. A dedicated disk-assisted +queue with (a maximum of) 5 worker threads is used, to avoid affecting +other log destinations in moments of high load. The ``confirmMessages`` +flag is enabled, which tells rsyslog to wait for the program to confirm +its initialization and each message received. The purpose of this setup +is preventing logs from being lost because of database connection +failures. + +If the program cannot write a log to the database, it will return a +negative confirmation to rsyslog via stdout. Rsyslog will then keep the +failed log in the queue, and send it again to the program after 5 +seconds. The program can also write error details to stderr, which will +be captured by rsyslog and written to ``/var/log/db_forward.log``. If +no response is received from the program within a 30-second timeout, +rsyslog will kill and restart it. + +.. code-block:: none + + module(load="omprog") + + action(type="omprog" + name="db_forward" + binary="/usr/libexec/rsyslog/db_forward.py" + confirmMessages="on" + confirmTimeout="30000" + queue.type="LinkedList" + queue.saveOnShutdown="on" + queue.workerThreads="5" + action.resumeInterval="5" + killUnresponsive="on" + output="/var/log/db_forward.log") + +Note that the ``useTransactions`` flag is not used in this example. The +program stores and confirms each log individually. + + +|FmtObsoleteName| directives +============================ + +- **$ActionOMProgBinary** <binary> + The binary program to be executed. diff --git a/source/configuration/modules/omrabbitmq.rst b/source/configuration/modules/omrabbitmq.rst new file mode 100644 index 0000000..433abd4 --- /dev/null +++ b/source/configuration/modules/omrabbitmq.rst @@ -0,0 +1,404 @@ +********************************** +omrabbitmq: RabbitMQ output module +********************************** + +=========================== =========================================================================== +**Module Name:** **omrabbitmq** +**Authors:** Jean-Philippe Hilaire <jean-philippe.hilaire@pmu.fr> / Philippe Duveau <philippe.duveau@free.fr> / Hamid Maadani <hamid@dexo.tech> +=========================== =========================================================================== + + +Purpose +======= + +This module sends syslog messages into RabbitMQ server. +Only v6 configuration syntax is supported. + +**omrabbitmq is tested and is running in production with 8.x version of rsyslog.** + +Compile +======= + +To successfully compile omrabbitmq module you need `rabbitmq-c <https://github.com/alanxz/rabbitmq-c>`_ library version >= 0.4. + + ./configure --enable-omrabbitmq ... + +Configuration Parameters +======================== + +Action Parameters +----------------- + +host +^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "yes", "hostname\[:port\]\[ hostname2\[:port2\]\]", + +rabbitmq server(s). See HA configuration + +port +^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "no", "port", "5672" + +virtual\_host +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "yes", "path", + +virtual message broker + +user +^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "yes", "user", + +user name + +password +^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "yes", "password", + +user password + +ssl +^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "binary", "no", , "off" + +enable TLS for AMQP connection + +init_openssl +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "binary", "no", , "off" + +should rabbitmq-c initialize OpenSSL? This is included to prevent crashes caused by OpenSSL double initialization. Should stay off in most cases. ONLY turn on if SSL does not work due to OpenSSL not being initialized. + +verify_peer +^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "binary", "no", , "off" + +SSL peer verification + +verify_hostname +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "binary", "no", , "off" + +SSL certificate hostname verification + +ca_cert +^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "no", "file path", + +CA certificate to be used for the SSL connection + +heartbeat_interval +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "integer", "no", , "0" + +AMQP heartbeat interval in seconds. 0 means disabled, which is default. + +exchange +^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "no", "name", + +exchange name + +routing\_key +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "no", "name", + +value of routing key + +routing\_key\_template +^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "no", "template_name", + +template used to compute the routing key + +body\_template +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "no", "template", "StdJSONFmt" + +template used to compute the message body. If the template is an empty string the sent message will be %rawmsg% + +delivery\_mode +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "no", "TRANSIENT\|PERSISTANT", "TRANSIENT" + +persistence of the message in the broker + +expiration +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "no", "milliseconds", no expiration + +ttl of the amqp message + +populate\_properties +^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "binary", "no", , "off" + +fill timestamp, appid, msgid, hostname (custom header) with message informations + +content\_type +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "no", "value", + +content type as a MIME value + +declare\_exchange +^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "binary", "no", "off", + +Rsyslog tries to declare the exchange on startup. Declaration failure (already exists with different parameters or insufficient rights) is warned but does not cancel the module instance. + +recover\_policy +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "no", "check\_interval;short\_failure_interval; short\_failure\_nb\_max;graceful\_interval", "60;6;3;600" + +See HA configuration + +HA configuration +================ + +The module can use two rabbitmq server in a fail-over mode. To configure this mode, the host parameter has to reference the two rabbitmq servers separated by space. +Each server can be optionally completed with the port (useful when they are different). +One of the servers is chosen on startup as a preferred one. The module connects to this server with a fail-over policy which can be defined through the action parameter "recover_policy". + +The module launch a back-ground thread to monitor the connection. As soon as the connection fails, the thread retries to reestablish the connection and switch to the back-up server if needed to recover the service. While connected to backup server, the thread tries to reconnect to the preferred server using a "recover_policy". This behaviour allow to load balance the client across the two rabbitmq servers on normal conditions, switch to the running server in case of failure and rebalanced on the two server as soon as the failed server is recovered without restarting clients. + +The recover policy is based on 4 parameters : + +- `check_interval` is the base duration between connection retries (default is 60 seconds) + +- `short_failure_interval` is a duration under which two successive failures are considered as abnormal for the rabbitmq server (default is `check_interval/10`) + +- `short_failure_nb_max` is the number of successive short failure are detected before to apply the graceful interval (default is 3) + +- `graceful_interval` is a longer duration used if the rabbitmq server is unstable (default is `check_interval*10`). + +The short failures detection is applied in case of unstable network or server and force to switch to back-up server for at least 'graceful-interval' avoiding heavy load on the unstable server. This can avoid dramatic scenarios in a multisites deployment. + +Examples +======== + +Example 1 +--------- + +This is the simplest action : + +- No High Availability + +- The routing-key is constant + +- The sent message use JSON format + +.. code-block:: none + + module(load='omrabbitmq') + action(type="omrabbitmq" + host="localhost" + virtual_host="/" + user="guest" + password="guest" + exchange="syslog" + routing_key="syslog.all") + +Example 2 +--------- + +Action characteristics : + +- No High Availability + +- The routing-key is computed + +- The sent message is a raw message + +.. code-block:: none + + module(load='omrabbitmq') + template(name="rkTpl" type="string" string="%syslogtag%.%syslogfacility-text%.%syslogpriority-text%") + + action(type="omrabbitmq" + host="localhost" + virtual_host="/" + user="guest" + password="guest" + exchange="syslog" + routing_key_template="rkTpl" + template_body="") + +Example 3 +--------- + +HA action : + +- High Availability between `server1:5672` and `server2:1234` + +- The routing-key is computed + +- The sent message is formatted using RSYSLOG_ForwardFormat standard template + +.. code-block:: none + + module(load='omrabbitmq') + template(name="rkTpl" type="string" string="%syslogtag%.%syslogfacility-text%.%syslogpriority-text%") + + action(type="omrabbitmq" + host="server1 server2:1234" + virtual_host="production" + user="guest" + password="guest" + exchange="syslog" + routing_key_template="rkTpl" + template_body="RSYSLOG_ForwardFormat") + +Example 4 +--------- + +SSL enabled connection, with Heartbeat : + +- No High Availability + +- The routing-key is constant + +- The sent message use JSON format + +- Heartbeat is set to 20 seconds + +.. code-block:: none + + module(load='omrabbitmq') + action(type="omrabbitmq" + host="localhost" + virtual_host="/" + user="guest" + password="guest" + ssl="on" + verify_peer="off" + verify_hostname="off" + heartbeat_interval="20" + exchange="syslog" + routing_key="syslog.all") diff --git a/source/configuration/modules/omrelp.rst b/source/configuration/modules/omrelp.rst new file mode 100644 index 0000000..11a3fd9 --- /dev/null +++ b/source/configuration/modules/omrelp.rst @@ -0,0 +1,482 @@ +************************** +omrelp: RELP Output Module +************************** + +=========================== =========================================================================== +**Module Name:** **omrelp** +**Author:** `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com> +=========================== =========================================================================== + + +Purpose +======= + +This module supports sending syslog messages over the reliable RELP +protocol. For RELP's advantages over plain tcp syslog, please see the +documentation for :doc:`imrelp <imrelp>` (the server counterpart). + +Setup + +Please note that `librelp <http://www.librelp.com>`__ is required for +imrelp (it provides the core relp protocol implementation). + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + +Module Parameters +----------------- + +tls.tlslib +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +.. versionadded:: 8.1903.0 + +Permits to specify the TLS library used by librelp. +All relp protocol operations or actually performed by librelp and +not rsyslog itself. This value specified is directly passed down to +librelp. Depending on librelp version and build parameters, supported +tls libraries differ (or TLS may not be supported at all). In this case +rsyslog emits an error message. + +Usually, the following options should be available: "openssl", "gnutls". + +Note that "gnutls" is the current default for historic reasons. We actually +recommend to use "openssl". It provides better error messages and accepts +a wider range of certificate types. + +If you have problems with the default setting, we recommend to switch to +"openssl". + + +Action Parameters +----------------- + +Target +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "yes", "none" + +The target server to connect to. + + +Port +^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "514", "no", "none" + +Name or numerical value of TCP port to use when connecting to target. + + +Template +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "RSYSLOG_ForwardFormat", "no", "none" + +Defines the template to be used for the output. + + +Timeout +^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "int", "90", "no", "none" + +Timeout for relp sessions. If set too low, valid sessions may be +considered dead and tried to recover. + + +Conn.Timeout +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "int", "10", "no", "none" + +Timeout for the socket connection. + + +RebindInterval +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "int", "0", "no", "none" + +Permits to specify an interval at which the current connection is +broken and re-established. This setting is primarily an aid to load +balancers. After the configured number of messages has been +transmitted, the current connection is terminated and a new one +started. This usually is perceived as a \`\`new connection'' by load +balancers, which in turn forward messages to another physical target +system. + + +WindowSize +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "int", "0", "no", "none" + +This is an **expert parameter**. It permits to override the RELP +window size being used by the client. Changing the window size has +both an effect on performance as well as potential message +duplication in failure case. A larger window size means more +performance, but also potentially more duplicated messages - and vice +versa. The default 0 means that librelp's default window size is +being used, which is considered a compromise between goals reached. +For your information: at the time of this writing, the librelp +default window size is 128 messages, but this may change at any time. +Note that there is no equivalent server parameter, as the client +proposes and manages the window size in RELP protocol. + + +TLS +^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +If set to "on", the RELP connection will be encrypted by TLS, so +that the data is protected against observers. Please note that both +the client and the server must have set TLS to either "on" or "off". +Other combinations lead to unpredictable results. + +*Attention when using GnuTLS 2.10.x or older* + +Versions older than GnuTLS 2.10.x may cause a crash (Segfault) under +certain circumstances. Most likely when an imrelp inputs and an +omrelp output is configured. The crash may happen when you are +receiving/sending messages at the same time. Upgrade to a newer +version like GnuTLS 2.12.21 to solve the problem. + + +TLS.Compression +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +The controls if the TLS stream should be compressed (zipped). While +this increases CPU use, the network bandwidth should be reduced. Note +that typical text-based log records usually compress rather well. + + +TLS.PermittedPeer +^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "array", "none", "no", "none" + +Note: this parameter is mandatory depending on the value of +`TLS.AuthMode` but the code does currently not check this. + +Peer Places access restrictions on this forwarder. Only peers which +have been listed in this parameter may be connected to. This guards +against rouge servers and man-in-the-middle attacks. The validation +bases on the certificate the remote peer presents. + +This contains either remote system names or fingerprints, depending +on the value of parameter `TLS.AuthMode`. One or more values may be +entered. + +When a non-permitted peer is connected to, the refusal is logged +together with the given remote peer identify. This is especially +useful in *fingerprint* authentication mode: if the +administrator knows this was a valid request, he can simply add the +fingerprint by copy and paste from the logfile to rsyslog.conf. It +must be noted, though, that this situation should usually not happen +after initial client setup and administrators should be alert in this +case. + +Note that usually a single remote peer should be all that is ever +needed. Support for multiple peers is primarily included in support +of load balancing scenarios. If the connection goes to a specific +server, only one specific certificate is ever expected (just like +when connecting to a specific ssh server). +To specify multiple fingerprints, just enclose them in braces like +this: + +.. code-block:: none + + tls.permittedPeer=["SHA1:...1", "SHA1:....2"] + +To specify just a single peer, you can either specify the string +directly or enclose it in braces. + +Note that in *name* authentication mode wildcards are supported. +This can be done as follows: + +.. code-block:: none + + tls.permittedPeer="*.example.com" + +Of course, there can also be multiple names used, some with and +some without wildcards: + +.. code-block:: none + + tls.permittedPeer=["*.example.com", "srv1.example.net", "srv2.example.net"] + + +TLS.AuthMode +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +Sets the mode used for mutual authentication. Supported values are +either "*fingerprint*" or "*name*". Fingerprint mode basically is +what SSH does. It does not require a full PKI to be present, instead +self-signed certs can be used on all peers. Even if a CA certificate +is given, the validity of the peer cert is NOT verified against it. +Only the certificate fingerprint counts. + +In "name" mode, certificate validation happens. Here, the matching is +done against the certificate's subjectAltName and, as a fallback, the +subject common name. If the certificate contains multiple names, a +match on any one of these names is considered good and permits the +peer to talk to rsyslog. + +The permitted names or fingerprints are configured via +`TLS.PermittedPeer`. + + +About Chained Certificates +-------------------------- + +.. versionadded:: 8.2008.0 + +With librelp 1.7.0, you can use chained certificates. +If using "openssl" as tls.tlslib, we recommend at least OpenSSL Version 1.1 +or higher. Chained certificates will also work with OpenSSL Version 1.0.2, but +they will be loaded into the main OpenSSL context object making them available +to all librelp instances (omrelp/imrelp) within the same process. + +If this is not desired, you will require to run rsyslog in multiple instances +with different omrelp configurations and certificates. + + +TLS.CaCert +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +The CA certificate that can verify the machine certs. + + +TLS.MyCert +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +The machine public certificate. + + +TLS.MyPrivKey +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +The machine private key. + + +TLS.PriorityString +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +This parameter permits to specify the so-called "priority string" to +GnuTLS. This string gives complete control over all crypto +parameters, including compression setting. For this reason, when the +prioritystring is specified, the "tls.compression" parameter has no +effect and is ignored. +Full information about how to construct a priority string can be +found in the GnuTLS manual. At the time of this writing, this +information was contained in `section 6.10 of the GnuTLS +manual <http://gnutls.org/manual/html_node/Priority-Strings.html>`__. +**Note: this is an expert parameter.** Do not use if you do not +exactly know what you are doing. + +tls.tlscfgcmd +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "no", "none" + +.. versionadded:: 8.2001.0 + +The setting can be used if tls.tlslib is set to "openssl" to pass configuration commands to +the openssl libray. +OpenSSL Version 1.0.2 or higher is required for this feature. +A list of possible commands and their valid values can be found in the documentation: +https://www.openssl.org/docs/man1.0.2/man3/SSL_CONF_cmd.html + +The setting can be single or multiline, each configuration command is separated by linefeed (\n). +Command and value are separated by equal sign (=). Here are a few samples: + +Example 1 +--------- + +This will allow all protocols except for SSLv2 and SSLv3: + +.. code-block:: none + + tls.tlscfgcmd="Protocol=ALL,-SSLv2,-SSLv3" + + +Example 2 +--------- + +This will allow all protocols except for SSLv2, SSLv3 and TLSv1. +It will also set the minimum protocol to TLSv1.2 + +.. code-block:: none + + tls.tlscfgcmd="Protocol=ALL,-SSLv2,-SSLv3,-TLSv1 + MinProtocol=TLSv1.2" + +LocalClientIp +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +Omrelp uses ip_address as local client address while connecting +to remote logserver. + + +Examples +======== + +Sending msgs with omrelp +------------------------ + +The following sample sends all messages to the central server +"centralserv" at port 2514 (note that that server must run imrelp on +port 2514). + +.. code-block:: none + + module(load="omrelp") + action(type="omrelp" target="centralserv" port="2514") + + +Sending msgs with omrelp via TLS +------------------------------------ + +This is the same as the previous example but uses TLS (via OpenSSL) for +operations. + +Certificate files must exist at configured locations. Note that authmode +"certvalid" is not very strong - you may want to use a different one for +actual deployments. For details, see parameter descriptions. + +.. code-block:: none + + module(load="omrelp" tls.tlslib="openssl") + action(type="omrelp" + target="centralserv" port="2514" tls="on" + tls.cacert="tls-certs/ca.pem" + tls.mycert="tls-certs/cert.pem" + tls.myprivkey="tls-certs/key.pem" + tls.authmode="certvalid" + tls.permittedpeer="rsyslog") + + +|FmtObsoleteName| directives +============================ + +This module uses old-style action configuration to keep consistent with +the forwarding rule. So far, no additional configuration directives can +be specified. To send a message via RELP, use + +.. code-block:: none + + *.* :omrelp:<server>:<port>;<template> + + diff --git a/source/configuration/modules/omruleset.rst b/source/configuration/modules/omruleset.rst new file mode 100644 index 0000000..abba0b2 --- /dev/null +++ b/source/configuration/modules/omruleset.rst @@ -0,0 +1,184 @@ +****************************************** +omruleset: ruleset output/including module +****************************************** + +=========================== =========================================================================== +**Module Name:** **omruleset** +**Author:** `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com> +=========================== =========================================================================== + +.. warning:: + + This module is outdated and only provided to support configurations that + already use it. **Do no longer use it in new configurations.** It has + been replaced by the much more efficient `"call" RainerScript + statement <rainerscript_call.html>`_. The "call" statement supports + everything omruleset does, but in an easier to use way. + + +**Available Since**: 5.3.4 + +**Deprecated in**: 7.2.0+ + + +Purpose +======= + +This is a very special "output" module. It permits to pass a message +object to another rule set. While this is a very simple action, it +enables very complex configurations, e.g. it supports high-speed "and" +conditions, sending data to the same file in a non-racy way, +include-ruleset functionality as well as some high-performance +optimizations (in case the rule sets have the necessary queue +definitions). + +While it leads to a lot of power, this output module offers seemingly +easy functionality. The complexity (and capabilities) arise from how +everything can be combined. + +With this module, a message can be sent to processing to another +ruleset. This is somewhat similar to a "#include" in the C programming +language. However, one needs to keep on the mind that a ruleset can +contain its own queue and that a queue can run in various modes. + +Note that if no queue is defined in the ruleset, the message is enqueued +into the main message queue. This most often is not optimal and means +that message processing may be severely deferred. Also note that when the +ruleset's target queue is full and no free space can be acquired within +the usual timeout, the message object may actually be lost. This is an +extreme scenario, but users building an audit-grade system need to know +this restriction. For regular installations, it should not really be +relevant. + +**At minimum, be sure you understand the** +:doc:`$RulesetCreateMainQueue <../ruleset/rsconf1_rulesetcreatemainqueue>` +**directive as well as the importance of statement order in rsyslog.conf +before using omruleset!** + +**Recommended Use:** + +- create rulesets specifically for omruleset +- create these rulesets with their own main queue +- decent queueing parameters (sizes, threads, etc) should be used for + the ruleset main queue. If in doubt, use the same parameters as for + the overall main queue. +- if you use multiple levels of ruleset nesting, double check for + endless loops - the rsyslog engine does not detect these + + +|FmtObsoleteName| directives +============================ + +.. note:: + + Parameter names are case-insensitive. + +- **$ActionOmrulesetRulesetName** ruleset-to-submit-to + This directive specifies the name of the ruleset that the message + provided to omruleset should be submitted to. This ruleset must + already have been defined. Note that the directive is automatically + reset after each :omruleset: action and there is no default. This is + done to prevent accidental loops in ruleset definition, what can + happen very quickly. The :omruleset: action will NOT be honored if no + ruleset name has been defined. As usual, the ruleset name must be + specified in front of the action that it modifies. + + +Examples +======== + +Ruleset for Write-to-file action +-------------------------------- + +This example creates a ruleset for a write-to-file action. The idea here +is that the same file is written based on multiple filters, problems +occur if the file is used together with a buffer. That is because file +buffers are action-specific, and so some partial buffers would be +written. With omruleset, we create a single action inside its own +ruleset and then pass all messages to it whenever we need to do so. Of +course, such a simple situation could also be solved by a more complex +filter, but the method used here can also be utilized in more complex +scenarios (e.g. with multiple listeners). The example tries to keep it +simple. Note that we create a ruleset-specific main queue (for +simplicity with the default main queue parameters) in order to avoid +re-queueing messages back into the main queue. + +.. code-block:: none + + $ModLoad omruleset # define ruleset for commonly written file + $RuleSet CommonAction + $RulesetCreateMainQueue on + *.* /path/to/file.log + + #switch back to default ruleset + $ruleset RSYSLOG_DefaultRuleset + + # begin first action + # note that we must first specify which ruleset to use for omruleset: + $ActionOmrulesetRulesetName CommonAction + mail.info :omruleset: + # end first action + + # begin second action + # note that we must first specify which ruleset to use for omruleset: + $ActionOmrulesetRulesetName CommonAction + :FROMHOST, isequal, "myhost.example.com" :omruleset: + #end second action + + # of course, we can have "regular" actions alongside :omrulset: actions + *.* /path/to/general-message-file.log + + +High-performance filter condition +--------------------------------- + +The next example is used to create a high-performance nested and filter +condition. Here, it is first checked if the message contains a string +"error". If so, the message is forwarded to another ruleset which then +applies some filters. The advantage of this is that we can use +high-performance filters where we otherwise would need to use the (much +slower) expression-based filters. Also, this enables pipeline +processing, in that second ruleset is executed in parallel to the first +one. + +.. code-block:: none + + $ModLoad omruleset + # define "second" ruleset + $RuleSet nested + $RulesetCreateMainQueue on + # again, we use our own queue + mail.* /path/to/mailerr.log + kernel.* /path/to/kernelerr.log + auth.* /path/to/autherr.log + + #switch back to default ruleset + $ruleset RSYSLOG_DefaultRuleset + + # begin first action - here we filter on "error" + # note that we must first specify which ruleset to use for omruleset: + $ActionOmrulesetRulesetName nested + :msg, contains, "error" :omruleset: + #end first action + + # begin second action - as an example we can do anything else in + # this processing. Note that these actions are processed concurrently + # to the ruleset "nested" + :FROMHOST, isequal, "myhost.example.com" /path/to/host.log + #end second action + + # of course, we can have "regular" actions alongside :omrulset: actions + *.* /path/to/general-message-file.log + + +Caveats/Known Bugs +================== + +The current configuration file language is not really adequate for a +complex construct like omruleset. Unfortunately, more important work is +currently preventing me from redoing the config language. So use extreme +care when nesting rulesets and be sure to test-run your config before +putting it into production, ensuring you have a sufficiently large probe +of the traffic run over it. If problems arise, the `rsyslog debug +log <troubleshoot.html>`_ is your friend. + diff --git a/source/configuration/modules/omsnmp.rst b/source/configuration/modules/omsnmp.rst new file mode 100644 index 0000000..ba283f5 --- /dev/null +++ b/source/configuration/modules/omsnmp.rst @@ -0,0 +1,265 @@ +******************************* +omsnmp: SNMP Trap Output Module +******************************* + +=========================== =========================================================================== +**Module Name:** **omsnmp** +**Author:** Andre Lorbach <alorbach@adiscon.com> +=========================== =========================================================================== + + +Purpose +======= + +Provides the ability to send syslog messages as an SNMPv1 & v2c traps. +By default, SNMPv2c is preferred. The syslog message is wrapped into a +OCTED STRING variable. This module uses the +`NET-SNMP <http://net-snmp.sourceforge.net/>`_ library. In order to +compile this module, you will need to have the +`NET-SNMP <http://net-snmp.sourceforge.net/>`_ developer (headers) +package installed. + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + +Action Parameters +----------------- + +Server +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "yes", "``$actionsnmptarget``" + +This can be a hostname or ip address, and is our snmp target host. +This parameter is required, if the snmptarget is not defined, nothing +will be send. + + +Port +^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "162", "no", "``$actionsnmptargetport``" + +The port which will be used, common values are port 162 or 161. + + +Transport +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "udp", "no", "``$actionsnmptransport``" + +Defines the transport type you wish to use. Technically we can +support all transport types which are supported by NET-SNMP. +To name a few possible values: +udp, tcp, udp6, tcp6, icmp, icmp6 ... + + +Version +^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "1", "no", "``$actionsnmpversion``" + +There can only be two choices for this parameter for now. +0 means SNMPv1 will be used. +1 means SNMPv2c will be used. +Any other value will default to 1. + + +Community +^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "public", "no", "``$actionsnmpcommunity``" + +This sets the used SNMP Community. + + +TrapOID +^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "1.3.6.1.4.1.19406.1.2.1", "no", "``$actionsnmptrapoid``" + +The default value means "ADISCON-MONITORWARE-MIB::syslogtrap". + +This configuration parameter is used for **SNMPv2** only. +This is the OID which defines the trap-type, or notification-type +rsyslog uses to send the trap. +In order to decode this OID, you will need to have the +ADISCON-MONITORWARE-MIB and ADISCON-MIB mibs installed on the +receiver side. Downloads of these mib files can be found here: + +`http://www.adiscon.org/download/ADISCON-MIB.txt <http://www.adiscon.org/download/ADISCON-MIB.txt>`_ + +`http://www.adiscon.org/download/ADISCON-MONITORWARE-MIB.txt <http://www.adiscon.org/download/ADISCON-MONITORWARE-MIB.txt>`_ +Thanks to the net-snmp mailinglist for the help and the +recommendations ;). + + +MessageOID +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "1.3.6.1.4.1.19406.1.2.1", "no", "``$actionsnmpsyslogmessageoid``" + +This OID will be used as a variable, type "OCTET STRING". This +variable will contain up to 255 characters of the original syslog +message including syslog header. It is recommend to use the default +OID. +In order to decode this OID, you will need to have the +ADISCON-MONITORWARE-MIB and ADISCON-MIB mibs installed on the +receiver side. To download these custom mibs, see the description of +**TrapOID**. + + +EnterpriseOID +^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "1.3.6.1.4.1.3.1.1", "no", "``$actionsnmpenterpriseoid``" + +The default value means "enterprises.cmu.1.1" + +Customize this value if needed. I recommend to use the default value +unless you require to use a different OID. +This configuration parameter is used for **SNMPv1** only. It has no +effect if **SNMPv2** is used. + + +SpecificType +^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "``$actionsnmpspecifictype``" + +This is the specific trap number. This configuration parameter is +used for **SNMPv1** only. It has no effect if **SNMPv2** is used. + + +Snmpv1DynSource +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "", "no", "none" + +.. versionadded:: 8.2001 + +If set, the source field of the SNMP trap can be overwritten with the a +template. The internal default is "%fromhost-ip%". The result should be a +valid IPv4 Address. Otherwise setting the source will fail. + +Below is a sample template called "dynsource" which you canm use to set the +source to a custom property: + +.. code-block:: none + + set $!custom_host = $fromhost; + template(name="dynsource" type="list") { + property(name="$!custom_host") + } + + +This configuration parameter is used for **SNMPv1** only. +It has no effect if **SNMPv2** is used. + + +TrapType +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "6", "no", "``$actionsnmptraptype``" + +There are only 7 Possible trap types defined which can be used here. +These trap types are: + +.. code-block:: none + + 0 = SNMP_TRAP_COLDSTART + 1 = SNMP_TRAP_WARMSTART + 2 = SNMP_TRAP_LINKDOWN + 3 = SNMP_TRAP_LINKUP + 4 = SNMP_TRAP_AUTHFAIL + 5 = SNMP_TRAP_EGPNEIGHBORLOSS + 6 = SNMP_TRAP_ENTERPRISESPECIFIC + +.. note:: + + Any other value will default to 6 automatically. This configuration + parameter is used for **SNMPv1** only. It has no effect if **SNMPv2** + is used. + + +Caveats/Known Bugs +================== + +- In order to decode the custom OIDs, you will need to have the adiscon + mibs installed. + + +Examples +======== + +Sending messages as snmp traps +------------------------------ + +The following commands send every message as a snmp trap. + +.. code-block:: none + + module(load="omsnmp") + action(type="omsnmp" server="localhost" port="162" transport="udp" + version="1" community="public") + diff --git a/source/configuration/modules/omstdout.rst b/source/configuration/modules/omstdout.rst new file mode 100644 index 0000000..ee2ddf3 --- /dev/null +++ b/source/configuration/modules/omstdout.rst @@ -0,0 +1,113 @@ +*********************************************** +omstdout: stdout output module (testbench tool) +*********************************************** + +=========================== =========================================================================== +**Module Name:** **omstdout** +**Author:** `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com> +**Available Since:** 4.1.6 +=========================== =========================================================================== + + +Purpose +======= + +This module writes any messages that are passed to it to stdout. It +was developed for the rsyslog test suite. However, there may (limited) +exist some other usages. Please note we do not put too much effort on +the quality of this module as we do not expect it to be used in real +deployments. If you do, please drop us a note so that we can enhance +its priority! + + +Configuration +============= + +.. note:: + + Parameter names are case-insensitive. + + +Module Parameters +----------------- + +none + + +Action Parameters +----------------- + +template +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "RSYSLOG_FileFormat", "no", "none" + +Set the template which will be used for the output. If none is specified +the default will be used. + + +EnsureLFEnding +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "on", "no", "``$ActionOMStdoutEnsureLFEnding``" + +Makes sure, that each message is written with a terminating LF. If the +message contains a trailing LF, none is added. This is needed for the +automated tests. + + +Configure statement +------------------- + +This is used when building rsyslog from source. + +./configure --enable-omstdout + + +Legacy parameter not adopted in the new style +--------------------------------------------- + +- **$ActionOMStdoutArrayInterface** + [Default: off] + This setting instructs omstdout to use the alternate array based + method of parameter passing. If used, the values will be output with + commas between the values but no other padding bytes. This is a test + aid for the alternate calling interface. + + +Examples +======== + +Minimum setup +------------- + +The following sample is the minimum setup required to have syslog messages +written to stdout. + +.. code-block:: none + + module(load="omstdout") + action(type="omstdout") + + +Example 2 +--------- + +The following sample will write syslog messages to stdout, using a template. + +.. code-block:: none + + module(load="omstdout") + action(type="omstdout" template="outfmt") + + diff --git a/source/configuration/modules/omudpspoof.rst b/source/configuration/modules/omudpspoof.rst new file mode 100644 index 0000000..2edb106 --- /dev/null +++ b/source/configuration/modules/omudpspoof.rst @@ -0,0 +1,209 @@ +************************************** +omudpspoof: UDP spoofing output module +************************************** + +=========================== =========================================================================== +**Module Name:** **omudpspoof** +**Author:** David Lang <david@lang.hm> and `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com> +**Available Since:** 5.1.3 +=========================== =========================================================================== + + +Purpose +======= + +This module is similar to the regular UDP forwarder, but permits to +spoof the sender address. Also, it enables to circle through a number of +source ports. + +**Important**: This module **requires root permissions**. This is a hard +requirement because raw socket access is necessary to fake UDP sender +addresses. As such, rsyslog cannot drop privileges if this module is +to be used. Ensure that you do **not** use `$PrivDropToUser` or +`$PrivDropToGroup`. Many distro default configurations (notably Ubuntu) +contain these statements. You need to remove or comment them out if you +want to use `omudpspoof`. + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + +Module Parameters +----------------- + +Template +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "RSYSLOG_TraditionalForwardFormat", "no", "none" + +This setting instructs omudpspoof to use a template different from +the default template for all of its actions that do not have a +template specified explicitly. + + +Action Parameters +----------------- + +Target +^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "yes", "``$ActionOMUDPSpoofTargetHost``" + +Host that the messages shall be sent to. + + +Port +^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "514", "no", "``$ActionOMUDPSpoofTargetPort``" + +Remote port that the messages shall be sent to. Default is 514. + + +SourceTemplate +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "RSYSLOG_omudpspoofDfltSourceTpl", "no", "``$ActionOMOMUDPSpoofSourceNameTemplate``" + +This is the name of the template that contains a numerical IP +address that is to be used as the source system IP address. While it +may often be a constant value, it can be generated as usual via the +property replacer, as long as it is a valid IPv4 address. If not +specified, the build-in default template +RSYSLOG\_omudpspoofDfltSourceTpl is used. This template is defined as +follows: +$template RSYSLOG\_omudpspoofDfltSourceTpl,"%fromhost-ip%" +So in essence, the default template spoofs the address of the system +the message was received from. This is considered the most important +use case. + + +SourcePort.start +^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "32000", "no", "``$ActionOMUDPSpoofSourcePortStart``" + +Specify the start value for circling the source ports. Start must be +less than or equal to sourcePort.End. + + +SourcePort.End +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "42000", "no", "``$ActionOMUDPSpoofSourcePortEnd``" + +Specify the end value for circling the source ports. End must be +equal to or more than sourcePort.Start. + + +MTU +^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "1500", "no", "none" + +Maximum packet length to send. + + +Template +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "RSYSLOG_TraditionalForwardFormat", "no", "``$ActionOMUDPSpoofDefaultTemplate``" + +This setting instructs omudpspoof to use a template different from +the default template for all of its actions that do not have a +template specified explicitly. + + +Caveats/Known Bugs +================== + +- **IPv6** is currently not supported. If you need this capability, + please let us know via the rsyslog mailing list. + +- Throughput is MUCH smaller than when using omfwd module. + + +Examples +======== + +Forwarding message through multiple ports +----------------------------------------- + +Forward the message to 192.168.1.1, using original source and port between 10000 and 19999. + +.. code-block:: none + + Action ( + type="omudpspoof" + target="192.168.1.1" + sourceport.start="10000" + sourceport.end="19999" + ) + + +Forwarding message using another source address +----------------------------------------------- + +Forward the message to 192.168.1.1, using source address 192.168.111.111 and default ports. + +.. code-block:: none + + Module ( + load="omudpspoof" + ) + Template ( + name="spoofaddr" + type="string" + string="192.168.111.111" + ) + Action ( + type="omudpspoof" + target="192.168.1.1" + sourcetemplate="spoofaddr" + ) + + diff --git a/source/configuration/modules/omusrmsg.rst b/source/configuration/modules/omusrmsg.rst new file mode 100644 index 0000000..ec00956 --- /dev/null +++ b/source/configuration/modules/omusrmsg.rst @@ -0,0 +1,67 @@ +********************** +omusrmsg: notify users +********************** + +=========================== =========================================================================== +**Module Name:** **omusrmsg** +**Author:** `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com> +=========================== =========================================================================== + + +Purpose +======= + +This module permits to send log messages to the user terminal. This is a +built-in module so it doesn't need to be loaded. + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + + +Action Parameters +----------------- + +Users +^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "none", "yes", "none" + +The name of the users to send data to. + + +Template +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "WallFmt/StdUsrMsgFmt", "no", "none" + +Template to user for the message. Default is WallFmt when parameter users is +"*" and StdUsrMsgFmt otherwise. + + +Examples +======== + +Write emergency messages to all users +------------------------------------- + +The following command writes emergency messages to all users + +.. code-block:: none + + action(type="omusrmsg" users="*") + diff --git a/source/configuration/modules/omuxsock.rst b/source/configuration/modules/omuxsock.rst new file mode 100644 index 0000000..a9ba8cd --- /dev/null +++ b/source/configuration/modules/omuxsock.rst @@ -0,0 +1,61 @@ +************************************ +omuxsock: Unix sockets Output Module +************************************ + +=========================== =========================================================================== +**Module Name:** **omuxsock** +**Author:** `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com> +**Available since:** 4.7.3, 5.5.7 +=========================== =========================================================================== + + +Purpose +======= + +This module supports sending syslog messages to local Unix sockets. Thus +it provided a fast message-passing interface between different rsyslog +instances. The counterpart to omuxsock is `imuxsock <imuxsock.html>`_. +Note that the template used together with omuxsock must be suitable to +be processed by the receiver. + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + +|FmtObsoleteName| directives +---------------------------- + +- **$OMUxSockSocket** + Name of the socket to send data to. This has no default and **must** + be set. +- **$OMUxSockDefaultTemplate** + This can be used to override the default template to be used + together with omuxsock. This is primarily useful if there are many + forwarding actions and each of them should use the same template. + + +Caveats/Known Bugs +================== + +Currently, only datagram sockets are supported. + + +Examples +======== + +Write all messages to socket +---------------------------- + +The following sample writes all messages to the "/tmp/socksample" +socket. + +.. code-block:: none + + $ModLoad omuxsock + $OMUxSockSocket /tmp/socksample + *.* :omuxsock: + diff --git a/source/configuration/modules/pmciscoios.rst b/source/configuration/modules/pmciscoios.rst new file mode 100644 index 0000000..dc82e43 --- /dev/null +++ b/source/configuration/modules/pmciscoios.rst @@ -0,0 +1,183 @@ +********** +pmciscoios +********** + +=========================== =========================================================================== +**Module Name:** **pmciscoios** +**Author:** `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com> +**Available since:** 8.3.4+ +=========================== =========================================================================== + + +Purpose +======= + +This is a parser that understands Cisco IOS "syslog" format. Note +that this format is quite different from RFC syslog format, and +so the default parser chain cannot deal with it. + +Note that due to large differences in IOS logging format, pmciscoios +may currently not be able to handle all possible format variations. +Nevertheless, it should be fairly easy to adapt it to additional +requirements. So be sure to ask if you run into problems with +format issues. + +Note that if your Cisco system emits timezone information in a supported +format, rsyslog will pick it up. In order to apply proper timezone offsets, +the timezone ids (e.g. "EST") must be configured via the +:doc:`timezone object <../timezone>`. + +Note if the clock on the Cisco device has not been set and cannot be +verified the Cisco will prepend the timestamp field with an asterisk (*). +If the clock has gone out of sync with its configured NTP server the +timestamp field will be prepended with a dot (.). In both of these cases +parsing the timestamp would fail, therefore any preceding asterisks (*) or +dots (.) are ignored. This may lead to "incorrect" timestamps being logged. + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + + +Parser Parameters +----------------- + +present.origin +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +This setting tell the parser if the origin field is present inside +the message. Due to the nature of Cisco's logging format, the parser +cannot sufficiently correctly deduce if the origin field is present +or not (at least not with reasonable performance). As such, the parser +must be provided with that information. If the origin is present, +its value is stored inside the HOSTNAME message property. + + +present.xr +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +If syslog is received from an IOSXR device the syslog format will usually +start with the RSP/LC/etc that produced the log, then the timestamp. +It will also contain an additional syslog tag before the standard Cisco +%TAG, this tag references the process that produced the log. +In order to use this Cisco IOS parser module with XR format messages both +of these additional fields must be ignored. + + +Examples +======== + +Listening multiple devices, some emitting origin information and some not +------------------------------------------------------------------------- + +We assume a scenario where we have some devices configured to emit origin +information whereas some others do not. In order to differentiate between +the two classes, rsyslog accepts input on different ports, one per class. +For each port, an input() object is defined, which binds the port to a +ruleset that uses the appropriately-configured parser. Except for the +different parsers, processing shall be identical for both classes. In our +first example we do this via a common ruleset which carries out the +actual processing: + +.. code-block:: none + + module(load="imtcp") + module(load="pmciscoios") + + input(type="imtcp" port="10514" ruleset="withoutOrigin") + input(type="imtcp" port="10515" ruleset="withOrigin") + + ruleset(name="common") { + ... do processing here ... + } + + ruleset(name="withoutOrigin" parser="rsyslog.ciscoios") { + /* this ruleset uses the default parser which was + * created during module load + */ + call common + } + + parser(name="custom.ciscoios.withOrigin" type="pmciscoios" + present.origin="on") + ruleset(name="withOrigin" parser="custom.ciscoios.withOrigin") { + /* this ruleset uses the parser defined immediately above */ + call common + } + + +Date stamp immediately following the origin +------------------------------------------- + +The example configuration above is a good solution. However, it is possible +to do the same thing in a somewhat condensed way, but if and only if the date +stamp immediately follows the origin. In that case, the parser has a chance to +detect if the origin is present or not. The key point here is to make sure +the parser checking for the origin is given before the default one, in which +case the first on will detect it does not match an pass on to the next +one inside the parser chain. However, this comes at the expense of additional +runtime overhead. The example below is **not** good practice -- it is given +as a purely educational sample to show some fine details of how parser +definitions interact. In this case, we can use a single listener. + +.. code-block:: none + + module(load="imtcp") + module(load="pmciscoios") + + input(type="imtcp" port="10514" ruleset="ciscoBoth") + + parser(name="custom.ciscoios.withOrigin" type="pmciscoios" + present.origin="on") + ruleset(name="ciscoBoth" + parser=["custom.ciscoios.withOrigin", "rsyslog.ciscoios"]) { + ... do processing here ... + } + + +Handling Cisco IOS and IOSXR formats +------------------------------------ + +The following sample demonstrates how to handle Cisco IOS and IOSXR formats + +.. code-block:: none + + module(load="imudp") + module(load="pmciscoios") + + input(type="imudp" port="10514" ruleset="ios") + input(type="imudp" port="10515" ruleset="iosxr") + + ruleset(name="common") { + ... do processing here ... + } + + ruleset(name="ios" parser="rsyslog.ciscoios") { + call common + } + + parser(name="custom.ciscoios.withXr" type="pmciscoios" + present.xr="on") + ruleset(name="iosxr" parser="custom.ciscoios.withXr"] { + call common + } + + diff --git a/source/configuration/modules/pmdb2diag.rst b/source/configuration/modules/pmdb2diag.rst new file mode 100644 index 0000000..dc36977 --- /dev/null +++ b/source/configuration/modules/pmdb2diag.rst @@ -0,0 +1,146 @@ +************************************** +pmdb2diag: DB2 Diag file parser module +************************************** + +=========================== =========================================================================== +**Module Name:** **pmdb2diag** +**Authors:** Jean-Philippe Hilaire <jean-philippe.hilaire@pmu.fr> & Philippe Duveau <philippe.duveau@free.fr> +=========================== =========================================================================== + + +Purpose +======= + +The objective of this module is to extract timestamp, procid and appname form the log +lines without altering it + +The parser is acting after an imfile input. This implies that imfile must be configured +with needParse to setted to on. + +Compile +======= + +To successfully compile pmdb2diag module you need to add it via configure. + + ./configure --enable-pmdb2diag ... + +Configuration Parameters +======================== + +**Parser Name:** "db2.diag" + +The default value of parameter are defined with escapeLF on in imfile. + +timeformat +^^^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "string", "no", "see strptime manual","%Y-%m-%d-%H.%M.%S." + +Format of the timestamp in d2diag log included decimal separator between seconds and second fractions. + +timepos +^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "integer", "no", ,"0" + +Position of the timestamp in the db2 diag log. + +levelpos +^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "integer", "no", ,"59" + +Position of the severity (level) in the db2 diag log. + +pidstarttoprogstartshift +^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "mandatory", "format", "default" + :widths: auto + :class: parameter-table + + "integer", "no", ,"49" + +Position of the prog related to the pid (form beginning to beginning) in the db2 diag log. + +Examples +======== + +Example 1 +^^^^^^^^^ + +This is the simplest parsing with default values + +.. code-block:: none + + module(load="pmdb2diag") + ruleset(name="ruleDB2" parser="db2.diag") { + ... do something + } + input(type="imfile" file="db2diag.log" ruleset="ruleDB2" tag="db2diag" + startmsg.regex="^[0-9]{4}-[0-9]{2}-[0-9]{2}" escapelf="on" needparse="on") + + +Example 2 +^^^^^^^^^ + +Parsing with custom values + +.. code-block:: none + + module(load="pmdb2diag") + parser(type="pmdb2diag" name="custom.db2.diag" levelpos="57" + timeformat=""%y-%m-%d:%H.%M.%S.") + ruleset(name="ruleDB2" parser="custom.db2.diag") { + ... do something + } + input(type="imfile" file="db2diag.log" ruleset="ruleDB2" tag="db2diag" + startmsg.regex="^[0-9]{4}-[0-9]{2}-[0-9]{2}" escapelf="on" needparse="on") + +DB2 Log sample +^^^^^^^^^^^^^^ + +.. code-block:: none + + 2015-05-06-16.53.26.989402+120 E1876227378A1702 LEVEL: Info + PID : 4390948 TID : 89500 PROC : db2sysc 0 + INSTANCE: db2itst NODE : 000 DB : DBTEST + APPHDL : 0-14410 APPID: 10.42.2.166.36261.150506120149 + AUTHID : DBUSR HOSTNAME: dev-dbm1 + EDUID : 89500 EDUNAME: db2agent (DBTEST) 0 + FUNCTION: DB2 UDB, relation data serv, sqlrr_dispatch_xa_request, probe:703 + MESSAGE : ZRC=0x80100024=-2146435036=SQLP_NOTA "Transaction was not found" + DIA8036C XA error with request type of "". Transaction was not found. + DATA #1 : String, 27 bytes + XA Dispatcher received NOTA + CALLSTCK: (Static functions may not be resolved correctly, as they are resolved to the nearest symbol) + [0] 0x090000000A496B70 sqlrr_xrollback__FP14db2UCinterface + 0x11E0 + [1] 0x090000000A356764 sqljsSyncRollback__FP14db2UCinterface + 0x6E4 + [2] 0x090000000C1FAAA8 sqljsParseRdbAccessed__FP13sqljsDrdaAsCbP13sqljDDMObjectP14db2UCinterface + 0x529C + [3] 0x0000000000000000 ?unknown + 0x0 + [4] 0x090000000C23D260 @72@sqljsSqlam__FP14db2UCinterfaceP8sqeAgentb + 0x1174 + [5] 0x090000000C23CE54 @72@sqljsSqlam__FP14db2UCinterfaceP8sqeAgentb + 0xD68 + [6] 0x090000000D74AB90 @72@sqljsDriveRequests__FP8sqeAgentP14db2UCconHandle + 0xA8 + [7] 0x090000000D74B6A0 @72@sqljsDrdaAsInnerDriver__FP18SQLCC_INITSTRUCT_Tb + 0x5F8 + [8] 0x090000000B8F85AC RunEDU__8sqeAgentFv + 0x48C38 + [9] 0x090000000B876240 RunEDU__8sqeAgentFv + 0x124 + [10] 0x090000000CD90DFC EDUDriver__9sqzEDUObjFv + 0x130 + [11] 0x090000000BE01664 sqloEDUEntry + 0x390 + [12] 0x09000000004F5E10 _pthread_body + 0xF0 + [13] 0xFFFFFFFFFFFFFFFC ?unknown + 0xFFFFFFFF diff --git a/source/configuration/modules/pmlastmsg.rst b/source/configuration/modules/pmlastmsg.rst new file mode 100644 index 0000000..711612f --- /dev/null +++ b/source/configuration/modules/pmlastmsg.rst @@ -0,0 +1,68 @@ +**************************************** +pmlastmsg: last message repeated n times +**************************************** + +=========================== =========================================================================== +**Module Name:** **pmlastmsg** +**Author:** `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com> +**Available Since:** 5.5.6 +=========================== =========================================================================== + + +Purpose +======= + +Some syslogds are known to emit severity malformed messages with content +"last message repeated n times". These messages can mess up message +reception, as they lead to wrong interpretation with the standard +RFC3164 parser. Rather than trying to fix this issue in pmrfc3164, we +have created a new parser module specifically for these messages. The +reason is that some processing overhead is involved in processing these +messages (they must be recognized) and we would not like to place this +toll on every user but only on those actually in need of the feature. +Note that the performance toll is not large -- but if you expect a very +high message rate with tenthousands of messages per second, you will +notice a difference. + +This module should be loaded first inside :doc:`rsyslog's parser +chain </concepts/messageparser>`. It processes all those messages that +contain a PRI, then none or some spaces and then the exact text +(case-insensitive) "last message repeated n times" where n must be an +integer. All other messages are left untouched. + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + + +There do not currently exist any configuration parameters for this +module. + + +Examples +======== + +Systems emitting malformed "repeated msg" messages +-------------------------------------------------- + +This example is the typical use case, where some systems emit malformed +"repeated msg" messages. Other than that, the default :rfc:`5424` and +:rfc:`3164` parsers should be used. Note that when a parser is specified, +the default parser chain is removed, so we need to specify all three +parsers. We use this together with the default ruleset. + +.. code-block:: none + + module(load="pmlastmsg") + + parser(type="pmlastmsg" name="custom.pmlastmsg") + + ruleset(name="ruleset" parser=["custom.pmlastmsg", "rsyslog.rfc5424", + "rsyslog.rfc3164"]) { + ... do processing here ... + } + diff --git a/source/configuration/modules/pmnormalize.rst b/source/configuration/modules/pmnormalize.rst new file mode 100644 index 0000000..2a01dd5 --- /dev/null +++ b/source/configuration/modules/pmnormalize.rst @@ -0,0 +1,121 @@ +***************************************************** +Log Message Normalization Parser Module (pmnormalize) +***************************************************** + +=========================== =========================================================================== +**Module Name:** **pmnormalize** +**Author:** Pascal Withopf <pascalwithopf1@gmail.com> +**Available since:** 8.27.0 +=========================== =========================================================================== + + +Purpose +======= + +This parser normalizes messages with the specified rules and populates the +properties for further use. + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + + +Action Parameters +----------------- + +Rulebase +^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +Specifies which rulebase file is to use. If there are multiple +pmnormalize instances, each one can use a different file. However, a +single instance can use only a single file. This parameter or **rule** +MUST be given, because normalization can only happen based on a rulebase. +It is recommended that an absolute path name is given. Information on +how to create the rulebase can be found in the `liblognorm +manual <http://www.liblognorm.com/files/manual/index.html>`_. + + +Rule +^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "array", "none", "no", "none" + +Contains an array of strings which will be put together as the rulebase. +This parameter or **rulebase** MUST be given, because normalization can +only happen based on a rulebase. + + +UndefinedPropertyError +^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +With this parameter an error message is controlled, which will be put out +every time pmnormalize can't normalize a message. + + +Examples +======== + +Normalize msgs received via imtcp +--------------------------------- + +In this sample messages are received via imtcp. Then they are normalized with +the given rulebase and written to a file. + +.. code-block:: none + + module(load="imtcp") + module(load="pmnormalize") + + input(type="imtcp" port="13514" ruleset="ruleset") + + parser(name="custom.pmnormalize" type="pmnormalize" rulebase="/tmp/rules.rulebase") + + ruleset(name="ruleset" parser="custom.pmnormalize") { + action(type="omfile" file="/tmp/output") + } + + +Write normalized messages to file +--------------------------------- + +In this sample messages are received via imtcp. Then they are normalized with +the given rule array. After that they are written in a file. + +.. code-block:: none + + module(load="imtcp") + module(load="pmnormalize") + + input(type="imtcp" port="10514" ruleset="outp") + + parser(name="custom.pmnormalize" type="pmnormalize" rule=[ + "rule=:<%pri:number%> %fromhost-ip:ipv4% %hostname:word% %syslogtag:char-to:\\x3a%: %msg:rest%", + "rule=:<%pri:number%> %hostname:word% %fromhost-ip:ipv4% %syslogtag:char-to:\\x3a%: %msg:rest%"]) + + ruleset(name="outp" parser="custom.pmnormalize") { + action(type="omfile" File="/tmp/output") + } + diff --git a/source/configuration/modules/pmnull.rst b/source/configuration/modules/pmnull.rst new file mode 100644 index 0000000..3348cbf --- /dev/null +++ b/source/configuration/modules/pmnull.rst @@ -0,0 +1,123 @@ +********************************* +pmnull: Syslog Null Parser Module +********************************* + +=========================== =========================================================================== +**Module Name:** **pmnull** +**Author:** `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com> +=========================== =========================================================================== + + +Purpose +======= + +When a message is received it is tried to match a set of parsers to get +properties populated. This parser module sets all attributes to "" but rawmsg. +There usually should be no need to use this module. It may be useful to +process certain known-non-syslog messages. + +The pmnull module was originally written as some people thought it would +be nice to save 0.05% of time by not unnecessarily parsing the message. +We even doubt it is that amount of performance enhancement as the properties +need to be populated in any case, so the saving is really minimal (but exists). + +**If you just want to transmit or store messages exactly in the format that +they arrived in you do not need pmnull!** You can use the `rawmsg` property:: + + template(name="asReceived" type="string" string="%rawmsg%") + action(type="omfwd" target="server.example.net" template="asReceived") + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + + +Parser Parameters +----------------- + +Tag +^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "string", "", "no", "none" + +This setting sets the tag value to the message. + + +SyslogFacility +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "Facility", "1", "no", "none" + +This setting sets the syslog facility value. The default comes from the +rfc3164 standard. + + +SyslogSeverity +^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "Severity", "5", "no", "none" + +This setting sets the syslog severity value. The default comes from the +rfc3164 standard. + + +Examples +======== + +Process messages received via imtcp +----------------------------------- + +In this example messages are received through imtcp on port 13514. The +ruleset uses the parser pmnull which has the parameters tag, syslogfacility +and syslogseverity given. + +.. code-block:: none + + module(load="imtcp") + module(load="pmnull") + + input(type="imtcp" port="13514" ruleset="ruleset") + parser(name="custom.pmnull" type="pmnull" tag="mytag" syslogfacility="3" + syslogseverity="1") + + ruleset(name="ruleset" parser=["custom.pmnull", "rsyslog.pmnull"]) { + action(type="omfile" file="rsyslog.out.log") + } + + +Process messages with default parameters +---------------------------------------- + +In this example the ruleset uses the parser pmnull with the default parameters +because no specifics were given. + +.. code-block:: none + + module(load="imtcp") + module(load="pmnull") + + input(type="imtcp" port="13514" ruleset="ruleset") + parser(name="custom.pmnull" type="pmnull") + + ruleset(name="ruleset" parser="custom.pmnull") { + action(type="omfile" file="rsyslog.out.log") + } + diff --git a/source/configuration/modules/pmrfc3164.rst b/source/configuration/modules/pmrfc3164.rst new file mode 100644 index 0000000..46cff38 --- /dev/null +++ b/source/configuration/modules/pmrfc3164.rst @@ -0,0 +1,161 @@ +******************************************* +pmrfc3164: Parse RFC3164-formatted messages +******************************************* + +=========================== =========================================================================== +**Module Name:** **pmrfc3164** +**Author:** `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com> +=========================== =========================================================================== + + +Purpose +======= + +This parser module is for parsing messages according to the traditional/legacy +syslog standard :rfc:`3164` + +It is part of the default parser chain. + +The parser can also be customized to allow the parsing of specific formats, +if they occur. + + +Configuration Parameters +======================== + +.. note:: + + Parameter names are case-insensitive. + + +Parser Parameters +----------------- + +permit.squareBracketsInHostname +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +This setting tells the parser that hostnames that are enclosed by brackets +should omit the brackets. + + +permit.slashesInHostname +^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +.. versionadded:: 8.20.0 + +This setting tells the parser that hostnames may contain slashes. This +is useful when messages e.g. from a syslog-ng relay chain are received. +Syslog-ng puts the various relay hosts via slashes into the hostname +field. + + +permit.AtSignsInHostname +^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +.. versionadded:: 8.25.0 + +This setting tells the parser that hostnames may contain at-signs. This +is useful when messages are relayed from a syslog-ng server in rfc3164 +format. The hostname field sent by syslog-ng may be prefixed by the source +name followed by an at-sign character. + + +force.tagEndingByColon +^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +.. versionadded:: 8.25.0 + +This setting tells the parser that tag need to be ending by colon to be +valid. In others case, the tag is set to dash ("-") without changing +message. + + +remove.msgFirstSpace +^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +.. versionadded:: 8.25.0 + +Rfc3164 tell message is directly after tag including first white space. +This option tell to remove the first white space in message just after +reading. It make rfc3164 & rfc5424 syslog messages working in a better way. + + +detect.YearAfterTimestamp +^^^^^^^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "none" + +Some devices send syslog messages in a format that is similar to RFC3164, +but they also attach the year to the timestamp (which is not compliant to +the RFC). With regular parsing, the year would be recognized to be the +hostname and the hostname would become the syslogtag. This setting should +prevent this. It is also limited to years between 2000 and 2099, so +hostnames with numbers as their name can still be recognized correctly. But +everything in this range will be detected as a year. + + +Examples +======== + +Receiving malformed RFC3164 messages +------------------------------------ + +We assume a scenario where some of the devices send malformed RFC3164 +messages. The parser module will automatically detect the malformed +sections and parse them accordingly. + +.. code-block:: none + + module(load="imtcp") + + input(type="imtcp" port="514" ruleset="customparser") + + parser(name="custom.rfc3164" + type="pmrfc3164" + permit.squareBracketsInHostname="on" + detect.YearAfterTimestamp="on") + + ruleset(name="customparser" parser="custom.rfc3164") { + ... do processing here ... + } + diff --git a/source/configuration/modules/pmrfc3164sd.rst b/source/configuration/modules/pmrfc3164sd.rst new file mode 100644 index 0000000..aeb1517 --- /dev/null +++ b/source/configuration/modules/pmrfc3164sd.rst @@ -0,0 +1,5 @@ +pmrfc3164sd: Parse RFC5424 structured data inside RFC3164 messages +================================================================== + +A contributed module for supporting RFC5424 structured data inside +RFC3164 messages (not supported by the rsyslog team) diff --git a/source/configuration/modules/pmrfc5424.rst b/source/configuration/modules/pmrfc5424.rst new file mode 100644 index 0000000..21554b7 --- /dev/null +++ b/source/configuration/modules/pmrfc5424.rst @@ -0,0 +1,6 @@ +pmrfc5424: Parse RFC5424-formatted messages +=========================================== + +This is the new Syslog Standard. + +:rfc:`5424` diff --git a/source/configuration/modules/sigprov_gt.rst b/source/configuration/modules/sigprov_gt.rst new file mode 100644 index 0000000..b3cd092 --- /dev/null +++ b/source/configuration/modules/sigprov_gt.rst @@ -0,0 +1,94 @@ +GuardTime Log Signature Provider (gt) +===================================== + +**Signature Provider Name: gt** + +**Author:** Rainer Gerhards <rgerhards@adiscon.com> + +**Supported:** from 7.3.9 to 8.26.0 + +**Description**: + +Provides the ability to sign syslog messages via the GuardTime signature +services. + +**Configuration Parameters**: + +Note: parameter names are case-insensitive. + +Signature providers are loaded by omfile, when the provider is selected +in its "sig.providerName" parameter. Parameters for the provider are +given in the omfile action instance line. + +This provider creates a signature file with the same base name but the +extension ".gtsig" for each log file (both for fixed-name files as well +as dynafiles). Both files together form a set. So you need to archive +both in order to prove integrity. + +- **sig.hashFunction** <Hash Algorithm> + The following hash algorithms are currently supported: + + - SHA1 + - RIPEMD-160 + - SHA2-224 + - SHA2-256 + - SHA2-384 + - SHA2-512 + +- **sig.timestampService** <timestamper URL> + This provides the URL of the timestamper service. If not selected, a + default server is selected. This may not necessarily be a good one + for your region. + + *Note:* If you need to supply user credentials, you can add them to + the timestamper URL. If, for example, you have a user "user" with + password "pass", you can do so as follows: + + http://user:pass@timestamper.example.net + +- **sig.block.sizeLimit** <nbr-records> + The maximum number of records inside a single signature block. By + default, there is no size limit, so the signature is only written on + file closure. Note that a signature request typically takes between + one and two seconds. So signing to frequently is probably not a good + idea. + +- **sig.keepRecordHashes** <on/**off**> + Controls if record hashes are written to the .gtsig file. This + enhances the ability to spot the location of a signature breach, but + costs considerable disk space (65 bytes for each log record for + SHA2-512 hashes, for example). + +- **sig.keepTreeHashes** <on/**off**> + Controls if tree (intermediate) hashes are written to the .gtsig + file. This enhances the ability to spot the location of a signature + breach, but costs considerable disk space (a bit mire than the amount + sig.keepRecordHashes requries). Note that both Tree and Record hashes + can be kept inside the signature file. + +**See Also** + +- `How to sign log messages through signature provider + Guardtime <http://www.rsyslog.com/how-to-sign-log-messages-through-signature-provider-guardtime/>`_ + +**Caveats/Known Bugs:** + +- currently none known + +**Samples:** + +This writes a log file with it's associated signature file. Default +parameters are used. + +:: + + action(type="omfile" file="/var/log/somelog" sig.provider="gt") + +In the next sample, we use the more secure SHA2-512 hash function, sign +every 10,000 records and Tree and Record hashes are kept. + +:: + + action(type="omfile" file="/var/log/somelog" sig.provider="gt" + sig.hashfunction="SHA2-512" sig.block.sizelimit="10000" + sig.keepTreeHashes="on" sig.keepRecordHashes="on") diff --git a/source/configuration/modules/sigprov_ksi.rst b/source/configuration/modules/sigprov_ksi.rst new file mode 100644 index 0000000..99193cb --- /dev/null +++ b/source/configuration/modules/sigprov_ksi.rst @@ -0,0 +1,99 @@ +Keyless Signature Infrastructure Provider (ksi) +=============================================== + +**Signature Provider Name: ksi** + +**Author:** Rainer Gerhards <rgerhards@adiscon.com> + +**Supported:** from 8.11.0 to 8.26.0 + +**Description**: + +Provides the ability to sign syslog messages via the GuardTime KSI +signature services. + +**Configuration Parameters**: + +Note: parameter names are case-insensitive. + +Signature providers are loaded by omfile, when the provider is selected +in its "sig.providerName" parameter. Parameters for the provider are +given in the omfile action instance line. + +This provider creates a signature file with the same base name but the +extension ".ksisig" for each log file (both for fixed-name files as well +as dynafiles). Both files together form a set. So you need to archive +both in order to prove integrity. + +- **sig.hashFunction** <Hash Algorithm> + The following hash algorithms are currently supported: + + - SHA1 + - SHA2-256 + - RIPEMD-160 + - SHA2-224 + - SHA2-384 + - SHA2-512 + - RIPEMD-256 + - SHA3-244 + - SHA3-256 + - SHA3-384 + - SHA3-512 + - SM3 + +- **sig.aggregator.uri** <KSI Aggregator URL> + This provides the URL of the KSI Aggregator service provided by + guardtime and looks like this: + + ksi+tcp://[ip/dnsname]:3332 + +- **sig.aggregator.user** <KSI UserID> + Set your username provided by Guardtime here. + +- **sig.aggregator.key** <KSI Key / Password> + Set your key provided by Guardtime here. + +- **sig.block.sizeLimit** <nbr-records> + The maximum number of records inside a single signature block. By + default, there is no size limit, so the signature is only written on + file closure. Note that a signature request typically takes between + one and two seconds. So signing to frequently is probably not a good + idea. + +- **sig.keepRecordHashes** <on/**off**> + Controls if record hashes are written to the .gtsig file. This + enhances the ability to spot the location of a signature breach, but + costs considerable disk space (65 bytes for each log record for + SHA2-512 hashes, for example). + +- **sig.keepTreeHashes** <on/**off**> + Controls if tree (intermediate) hashes are written to the .gtsig + file. This enhances the ability to spot the location of a signature + breach, but costs considerable disk space (a bit mire than the amount + sig.keepRecordHashes requries). Note that both Tree and Record hashes + can be kept inside the signature file. + +**See Also** + + +**Caveats/Known Bugs:** + +- currently none known + +**Samples:** + +This writes a log file with it's associated signature file. Default +parameters are used. + +:: + + action(type="omfile" file="/var/log/somelog" sig.provider="ksi") + +In the next sample, we use the more secure SHA2-512 hash function, sign +every 10,000 records and Tree and Record hashes are kept. + +:: + + action(type="omfile" file="/var/log/somelog" sig.provider="ksi" + sig.hashfunction="SHA2-512" sig.block.sizelimit="10000" + sig.keepTreeHashes="on" sig.keepRecordHashes="on") diff --git a/source/configuration/modules/sigprov_ksi12.rst b/source/configuration/modules/sigprov_ksi12.rst new file mode 100644 index 0000000..d5b6ab7 --- /dev/null +++ b/source/configuration/modules/sigprov_ksi12.rst @@ -0,0 +1,135 @@ +KSI Signature Provider (rsyslog-ksi-ls12) +============================================================ + +**Module Name: rsyslog-ksi-ls12** + +**Available Since:** 8.27 + +**Author:** Guardtime & Adiscon + +Description +########### + +The ``rsyslog-ksi-ls12`` module enables record level log signing with Guardtime KSI Blockchain. KSI signatures provide long-term log integrity and prove the time of log records cryptographically using independent verification. + +Main features of the ``rsyslog-ksi-ls12`` module are: + +* Automated online signing of file output log. +* Efficient block-based signing with record-level verification. +* Log records removal detection. + +For best results use the ``rsyslog-ksi-ls12`` module together with Guardtime ``logksi`` tool, which will become handy in: + +* Signing recovery. +* Extension of KSI signatures inside the log signature file. +* Verification of the log using log signatures. +* Extraction of record-level signatures. +* Integration of log signature files (necessary when signing in async mode). + +Getting Started +############### + +To get started with log signing: + +- Sign up to the Guardtime tryout service to be able to connect to KSI blockchain: + `guardtime.com/technology/blockchain-developers <https://guardtime.com/technology/blockchain-developers>`_ +- Install the ``libksi`` library (v3.20 or later) + `(libksi install) <https://github.com/guardtime/libksi#installation>`_ +- Install the ``rsyslog-ksi-ls12`` module (same version as rsyslog) from Adiscon repository. +- Install the accompanying ``logksi`` tool (recommended v1.5 or later) + `(logksi install) <https://github.com/guardtime/logksi#installation>`_ + +The format of the output depends on signing mode enabled (synchronous (``sync``) or asynchronous (``async``)). + +- In ``sync`` mode, log signature file is written directly into file ``<logfile>.logsig``. This mode is blocking as issuing KSI signatures one at a time will halt actual writing of log lines into log files. This mode suits for a system where signatures are issued rarely and delay caused by signing process is acceptable. Advantage compared to ``async`` mode is that the user has no need to integrate intermediate files to get actual log signature. + +- In ``async`` mode, log signature intermediate files are written into directory ``<logfile>.logsig.parts``. This mode is not blocking enabling high availability and concurrent signing of several blocks at the same time. Log signature is divided into two files, where one contains info about log records and blocks, and the other contains KSI signatures issued asynchronously. To create ``<logfile>.logsig`` from ``<logfile>.logsig.parts``, use ``logksi integrate <logfile>``. Advantage compared to ``sync`` mode is much better operational stability and speed. + +Currently the log signing is only supported by the file output module, thus the action type must be ``omfile``. To activate signing, add the following parameters to the action of interest in your rsyslog configuration file: + +Mandatory parameters (no default value defined): + +- **sig.provider** specifies the signature provider; in case of ``rsyslog-ksi-ls12`` package this is ``"ksi_ls12"``. +- **sig.block.levelLimit** defines the maximum level of the root of the local aggregation tree per one block. The maximum number of log lines in one block is calculated as ``2^(levelLimit - 1)``. +- **sig.aggregator.url** defines the endpoint of the KSI signing service in KSI Gateway. In ``async`` mode it is possible to specify up to 3 endpoints for high availability service, where user credentials are integrated into URL. Supported URI schemes are: + + - *ksi+http://* + - *ksi+tcp://* + + Examples: + + - sig.aggregator.url="ksi+tcp://signingservice1.example.com" + + sig.aggregator.user="rsmith" + + sig.aggregator.key= "secret" + + - sig.aggregator.url="ksi+tcp://rsmith:secret@signingservice1.example.com|ksi+tcp://jsmith:terces@signingservice2.example.com" + +- **sig.aggregator.user** specifies the login name for the KSI signing service. For high availability service, credentials are specified in URI. +- **sig.aggregator.key** specifies the key for the login name. For high availability service, credentials are specified in URI. + +Optional parameters (if not defined, default value is used): + +- **sig.syncmode** defines the signing mode: ``"sync"`` (default) or ``"async"``. +- **sig.hashFunction** defines the hash function to be used for hashing, default is ``"SHA2-256"``. + Other SHA-2, as well as RIPEMED-160 functions are supported. +- **sig.block.timeLimit** defines the maximum duration of one block in seconds. + Default value ``"0"`` indicates that no time limit is set. +- **sig.block.signTimeout** specifies a time window within the block signatures + have to be issued, default is ``10``. For example, issuing 4 signatures in a + second with sign timeout 10s, it is possible to handle 4 x 10 signatures + request created at the same time. More than that, will close last blocks with + signature failure as signature requests were not sent out within 10 seconds. +- **sig.aggregator.hmacAlg** defines the HMAC algorithm to be used in communication with the KSI Gateway. + This must be agreed on with the KSI service provider, default is ``"SHA2-256"``. +- **sig.keepTreeHashes** turns on/off the storing of the hashes that were used as leaves + for building the Merkle tree, default is ``"off"``. +- **sig.keepRecordHashes** turns on/off the storing of the hashes of the log records, default is ``"on"``. +- **sig.confInterval** defines interval of periodic request for aggregator configuration in seconds, default is ``3600``. +- **sig.randomSource** defines source of random as file, default is ``"/dev/urandom"``. +- **sig.debugFile** enables libksi log and redirects it into file specified. Note that logger level has to be specified (see ``sig.debugLevel``). +- **sig.debugLevel** specifies libksi log level. Note that log file has to be specified (see ``sig.debugFile``). + + - *0* None (default). + - *1* Error. + - *2* Warning. + - *3* Notice. + - *4* Info. + - *5* Debug. + +The log signature file, which stores the KSI signatures and information about the signed blocks, appears in the same directory as the log file itself. + +Sample +###### + +To sign the logs in ``/var/log/secure`` with KSI: +:: + + # The authpriv file has restricted access and is signed with KSI + authpriv.* action(type="omfile" file="/var/log/secure" + sig.provider="ksi_ls12" + sig.syncmode="sync" + sig.hashFunction="SHA2-256" + sig.block.levelLimit="8" + sig.block.timeLimit="0" + sig.aggregator.url= + "http://tryout.guardtime.net:8080/gt-signingservice" + sig.aggregator.user="rsmith" + sig.aggregator.key="secret" + sig.aggregator.hmacAlg="SHA2-256" + sig.keepTreeHashes="off" + sig.keepRecordHashes="on") + + +Note that all parameter values must be between quotation marks! + +See Also +######## + +To better understand the log signing mechanism and the module's possibilities it is advised to consult with: + +- `KSI Rsyslog Integration User Guide <https://docs.guardtime.net/ksi-rsyslog-guide/>`_ +- `KSI Developer Guide <https://docs.guardtime.net/ksi-dev-guide/>`_ + +Access for both of these documents requires Guardtime tryout service credentials, available from `<https://guardtime.com/technology/blockchain-developers>`_ diff --git a/source/configuration/modules/workflow.rst b/source/configuration/modules/workflow.rst new file mode 100644 index 0000000..9df5f74 --- /dev/null +++ b/source/configuration/modules/workflow.rst @@ -0,0 +1,30 @@ +Where are the modules integrated into the Message Flow? +======================================================= + +Depending on their module type, modules may access and/or modify +messages at various stages during rsyslog's processing. Note that only +the "core type" (e.g. input, output) but not any type derived from it +(message modification module) specifies when a module is called. + +The simplified workflow is as follows: + +.. figure:: module_workflow.png + :align: center + :alt: module_workflow + +As can be seen, messages are received by input modules, then passed to +one or many parser modules, which generate the in-memory representation +of the message and may also modify the message itself. The internal +representation is passed to output modules, which may output a message +and (with the interfaces introduced in v5) may also modify +message object content. + +String generator modules are not included inside this picture, because +they are not a required part of the workflow. If used, they operate "in +front of" the output modules, because they are called during template +generation. + +Note that the actual flow is much more complex and depends a lot on +queue and filter settings. This graphic above is a high-level message +flow diagram. + diff --git a/source/configuration/nomatch.rst b/source/configuration/nomatch.rst new file mode 100644 index 0000000..9cb84b7 --- /dev/null +++ b/source/configuration/nomatch.rst @@ -0,0 +1,47 @@ +Property Replacer nomatch mode +------------------------------ + +**The "nomatch-Mode" specifies which string the property replacer shall +return if a regular expression did not find the search string.**. +Traditionally, the string "\*\*NO MATCH\*\*" was returned, but many +people complained this was almost never useful. Still, this mode is +support as "**DFLT**\ " for legacy configurations. + +Three additional and potentially useful modes exist: in one (**BLANK**) +a blank string is returned. This is probably useful for inserting values +into databases where no value shall be inserted if the expression could +not be found. + +A similar mode is "**ZERO**\ " where the string "0" is returned. This is +suitable for numerical values. A use case may be that you record a +traffic log based on firewall rules and the "bytes transmitted" counter +is extracted via a regular expression. If no "bytes transmitted" counter +is available in the current message, it is probably a good idea to +return an empty string, which the database layer can turn into a zero. + +The other mode is "**FIELD**\ ", in which the complete field is +returned. This may be useful in cases where absence of a match is +considered a failure and the message that triggered it shall be logged. + +If in doubt, **it is highly suggested to use the** `rsyslog online regular +expression checker and generator <http://www.rsyslog.com/tool-regex>`_ +**to see these options in action**. With that online tool, you can craft +regular expressions based on samples and try out the different modes. + +Summary of nomatch Modes +~~~~~~~~~~~~~~~~~~~~~~~~ + ++------------+-----------------------------------------------------------+ +| **Mode** | **Returned** | ++------------+-----------------------------------------------------------+ +| DFLT | "\*\*NO MATCH\*\*" | ++------------+-----------------------------------------------------------+ +| BLANK | "" (empty string) | ++------------+-----------------------------------------------------------+ +| ZERO | "0" | ++------------+-----------------------------------------------------------+ +| FIELD | full content of original field | ++------------+-----------------------------------------------------------+ +| | `Interactive Tool <http://www.rsyslog.com/tool-regex>`_ | ++------------+-----------------------------------------------------------+ + diff --git a/source/configuration/output_channels.rst b/source/configuration/output_channels.rst new file mode 100644 index 0000000..24e26c7 --- /dev/null +++ b/source/configuration/output_channels.rst @@ -0,0 +1,61 @@ +Output Channels +--------------- + +Output Channels are a new concept first introduced in rsyslog 0.9.0. +**As of this writing, it is most likely that they will be replaced by +something different in the future.** So if you use them, be prepared to +change you configuration file syntax when you upgrade to a later +release. +The idea behind output channel definitions is that it shall provide an +umbrella for any type of output that the user might want. In essence, +this is the "file" part of selector lines (and this is why we are not +sure output channel syntax will stay after the next review). There is a +difference, though: selector channels both have filter conditions +(currently facility and severity) as well as the output destination. +they can only be used to write to files - not pipes, ttys or whatever +Output channels define the output definition, only. As of this build, +else. If we stick with output channels, this will change over time. + +In concept, an output channel includes everything needed to know about +an output actions. In practice, the current implementation only carries +a filename, a maximum file size and a command to be issued when this +file size is reached. More things might be present in future version, +which might also change the syntax of the directive. + +Output channels are defined via an $outchannel directive. It's syntax is +as follows: +$outchannel name,file-name,max-size,action-on-max-size +name is the name of the output channel (not the file), file-name is the +file name to be written to, max-size the maximum allowed size and +action-on-max-size a command to be issued when the max size is reached. +This command always has exactly one parameter. The binary is that part +of action-on-max-size before the first space, its parameter is +everything behind that space. +Please note that max-size is queried BEFORE writing the log message to +the file. So be sure to set this limit reasonably low so that any +message might fit. For the current release, setting it 1k lower than you +expected is helpful. The max-size must always be specified in bytes - +there are no special symbols (like 1k, 1m,...) at this point of +development. +Keep in mind that $outchannel just defines a channel with "name". It +does not activate it. To do so, you must use a selector line (see +below). That selector line includes the channel name plus an $ sign in +front of it. A sample might be: +\*.\* :omfile:$mychannel +In its current form, output channels primarily provide the ability to +size-limit an output file. To do so, specify a maximum size. When this +size is reached, rsyslogd will execute the action-on-max-size command +and then reopen the file and retry. The command should be something like +a `log rotation script <log_rotation_fix_size.html>`_ or a similar +thing. + +If there is no action-on-max-size command or the command did not resolve +the situation, the file is closed and never reopened by rsyslogd +(except, of course, by huping it). This logic was integrated when we +first experienced severe issues with files larger 2gb, which could lead +to rsyslogd dumping core. In such cases, it is more appropriate to stop +writing to a single file. Meanwhile, rsyslogd has been fixed to support +files larger 2gb, but obviously only on file systems and operating +system versions that do so. So it can still make sense to enforce a 2gb +file size limit. + diff --git a/source/configuration/parser.rst b/source/configuration/parser.rst new file mode 100644 index 0000000..d54e0df --- /dev/null +++ b/source/configuration/parser.rst @@ -0,0 +1,87 @@ +Parser +====== + +.. index:: ! parser +.. _cfgobj_input: + +The ``parser`` object, as its name suggests, describes message parsers. +Message parsers have a standard parser name, which can be used by simply +loading the parser module. Only when specific parameters need to be set +the parser object is needed. + +In that case, it is used to define a new parser name (aka "parser definition") +which configures this name to use the parser module with set parameters. +This is important as the ruleset() object does not support to set parser +parameters. Instead, if parameters are needed, a proper parser name must +be defined using the parser() object. A parser name defined via the +parser() object can be used wherever a parser name can occur. + +Note that not all message parser modules are supported in the parser() +object. The reason is that many do not have any user-selectable +parameters and as such, there is no point in issuing a parser() object +for them. + +The parser object has different parameters: + +- those that apply to all parser and are generally available for + all of them. These are documented below. +- parser-specific parameters. These are specific to a certain parser + module. They are documented by the :doc:`parser module <modules/idx_parser>` + in question. + + +General Parser Parameters +------------------------- + +Note: parameter names are case-insensitive. + +.. function:: name <name-string> + + *Mandatory* + + This names the parser. Names starting with "rsyslog." are reserved for + rsyslog use and must not be used. It is suggested to replace "rsyslog." + with "custom." and keep the rest of the name descriptive. However, this + is not enforced and just good practice. + +.. function:: type <type-string> + + *Mandatory* + + The ``<type-string>`` is a string identifying the parser module as given + it each module's documentation. Do not mistake the parser module name + with its default parser name. + For example, the + :doc:`Cisco IOS message parser module <modules/pmciscoios>` parser module + name is "pmciscoios", whereas it's default parser name is + "rsyslog.pmciscoios". + +Samples +------- +The following example creates a custom parser definition and uses it within a ruleset: + +:: + + module(load="pmciscoios") + parser(name="custom.pmciscoios.with_origin" type="pmciscoios") + + ruleset(name="myRuleset" parser="custom.pmciscoios.with_origin") { + ... do something here ... + } + +The following example uses multiple parsers within a ruleset without a parser object (the order is important): + +:: + + module(load="pmaixforwardedfrom") + module(load="pmlastmsg") + + ruleset(name="myRuleset" parser=["rsyslog.lastline","rsyslog.aixforwardedfrom","rsyslog.rfc5424","rsyslog.rfc3164"]) { + ... do something here ... + } + + + +A more elaborate example can also be found in the +:doc:`Cisco IOS message parser module <modules/pmciscoios>` documentation. + diff --git a/source/configuration/percentile_stats.rst b/source/configuration/percentile_stats.rst new file mode 100644 index 0000000..cd9781d --- /dev/null +++ b/source/configuration/percentile_stats.rst @@ -0,0 +1,151 @@ +Percentile Stats +================ + +The Percentile Stats component allows user to configure statistical namespaces +(called stats-buckets), which can then be used to record statistical values for +publishing periodic percentiles and summaries. + + +Percentile Stats Configuration +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +Percentile-stats configuration involves a **two part setup**. First, define a ``percentile-stats`` bucket and +its attributes. Then, add statistics and observation values to the namespace, by making ``percentile_observation`` calls. + +percentile_stats(name="<bucket>", percentiles=[...], windowsize="<count>"...) (object) +----------------------------------------------------------------------------------------------------------- + +**Defines** the statistics bucket(identified by the bucket-name) and allows user to set some properties that control behavior of the bucket. + +.. code-block:: + + percentile_stats(name="bucket_name" percentiles=["95"] windowsize=1000) + +Parameters: + **name** <string literal, mandatory> : Bucket name of a set of statistics to sample. + + **percentiles** <array, mandatory> : A list of strings, with percentile statistic value between 1, 100 inclusive, user would like to publish to impstats. + This list of percentiles would apply for all statistics tracked under this bucket. + + **windowSize** <number, mandatory> : A max *sliding* window (FIFO) size - rounded *up* to the nearest power of 2, that is larger than the given window size. + Specifies the maximum number of observations stored over an impstats reporting interval. + This attribute would apply to all statistics tracked under this bucket. + + **delimiter** <string literal, default: "."> : A single character delimiter used in the published fully qualified statname. + This delimiter would apply to all statistics tracked under this bucket. + + +A definition setting all the parameters looks like: + +.. code-block:: + + percentile_stats(name="host_statistics" percentiles=["50", "95", "99"] windowsize="1000" delimiter="|") + + +percentile_observe("<bucket>", "<statname>", <value>) (function) +---------------------------------------------------------------- + +**Adds** a statistical sample to the statistic set identified by the <bucket>, and <statname>. +If the number of values exceed the defined **windowSize**, the earliest recorded value is dropped +and the new value is recorded. + +.. note:: + Sums and counts only include values found in the sliding window. + Min and Max summary values will include all values seen over an observation interval. + See :ref:`Reporting` below for more info on published summary statistics. + + + +Parameters: + **bucket name** <string literal, mandatory> : Name of the statistic bucket + + **stat name** <string literal, mandatory> : Name of the statistic to record (this name will be combined with a percentile and reported by impstats to identify the percentile) + + + **value** <expression resulting in an integer value, mandatory> : Value to record + +A ``percentile_observe`` call looks like: + +.. code-block:: + + set $.ret = percentile_observe("host_statistics", "msg_per_host", $.mycount); + + if ($.ret != 0) then { + .... + } + +``$.ret`` captures the error-code. It has value ``0`` when operation is successful and non-zero when it fails. It uses Rsyslog error-codes. + + +.. _Reporting: + +Reporting +^^^^^^^^^ + +The following example metrics would be reported by **impstats** + +Legacy format: + +.. code-block:: + + ... + global: origin=percentile host_statistics.new_metric_add=1 host_statistics.ops_overflow=0 + ... + host_statistics: origin=percentile.bucket msg_per_host|p95=1950 msg_per_host|p50=1500 msg_per_host|p99=1990 msg_per_host|window_min=1001 msg_per_host|window_max=2000 msg_per_host|window_sum=1500500 msg_per_host|window_count=1000 + ... + +Json(variants with the same structure are used in other Json based formats such as ``cee`` and ``json-elasticsearch``) format: + +.. code-block:: + + ... + { "name": "global", "origin": "percentile", "values": { "host_statistics.new_metric_add": 1, "host_statistics.ops_overflow": 0 } } + ... + { "name": "host_statistics", "origin": "percentile.bucket", "values": { "msg_per_host|p95": 1950, "msg_per_host|p50": 1500, "msg_per_host|p99": 1990, "msg_per_host|window_min": 1001, "msg_per_host|window_max": 2000, "msg_per_host|window_sum": 1500500, "msg_per_host|window_count": 1000 } } + ... + +In this case counters are encapsulated inside an object hanging off top-level-key ``values``. + +Fields +------ + +**global: origin=percentile.bucket**: + **new_metric_add**: Number of "new" metrics added (new counters created). + + **ops_overflow**: Number of operations ignored because number-of-counters-tracked has hit configured max-cardinality. + +**host_statistic: origin=percentile.bucket**: + **msg_per_host|<pXX>**: percentile value, identified by <stat name><delimiter><pXX>, where pXX is one of the requested ``percentiles`` requested. + + + **msg_per_host|window_min**: minimum recorded value in the statistical population window. Identified by ``<stat-name><delimiter>window_min`` + + + **msg_per_host|window_max**: maximum recorded value in the statistical population window. Identified by ``<stat-name><delimiter>window_max`` + + + **msg_per_host|window_sum**: sum of recorded values in the statistical population window. Identified by ``<stat-name>delimiter>window_sum`` + + + **msg_per_host|window_count**: count of recorded values in the statistical population window. Identified by ``<stat-name><delimiter>window_count`` + + +Implementation Details +---------------------- + +Percentile stats module uses a sliding window, sized according to the **windowSize** configuration parameter. +The percentile values are calculated, once every **impstats** interval. +Percentiles are calculated according to the standard “nearest-rank” method: + + + n = CEILING((P/100) x N) where: + +* n - index to percentile value +* P - percentile [1, 100] +* N - number of values recorded + + +.. note:: + In order to sort the values, a standard implementation of quicksort is used, which performs pretty well + on average. However quicksort quickly degrades when there are many repeated elements, thus it is best + to avoid repeated values if possible. diff --git a/source/configuration/properties.rst b/source/configuration/properties.rst new file mode 100644 index 0000000..863984f --- /dev/null +++ b/source/configuration/properties.rst @@ -0,0 +1,322 @@ +rsyslog Properties +================== + +Data items in rsyslog are called "properties". They can have different +origin. The most important ones are those that stem from received +messages. But there are also others. Whenever you want to access data items, +you need to access the respective property. + +Properties are used in + +- :doc:`templates <templates>` +- conditional statements + +The property name is case-insensitive (prior to 3.17.0, they were case-sensitive). + +Note: many users refer to "rsyslog properties" as "rsyslog variables". You can treat +them as synonymous. +Read how `rsyslog lead author Rainer Gerhards explains the naming +difference <https://rainer.gerhards.net/2020/08/rsyslog-template-variables-where-to-find-them.html">`_. + +Message Properties +------------------ +These are extracted by rsyslog parsers from the original message. All message +properties start with a letter. + +The following message properties exist: + +**msg** + the MSG part of the message (aka "the message" ;)) + +**rawmsg** + the message "as is". Should be useful for debugging and also if a message + should be forwarded totally unaltered. + Please notice *EscapecontrolCharactersOnReceive* is enabled by default, so + it may be different from what was received in the socket. + +**rawmsg-after-pri** + Almost the same as **rawmsg**, but the syslog PRI is removed. + If no PRI was present, **rawmsg-after-pri** is identical to + **rawmsg**. Note that the syslog PRI is header field that + contains information on syslog facility and severity. It is + enclosed in greater-than and less-than characters, e.g. + "<191>". This field is often not written to log files, but + usually needs to be present for the receiver to properly + classify the message. There are some rare cases where one + wants the raw message, but not the PRI. You can use this + property to obtain that. In general, you should know that you + need this format, otherwise stay away from the property. + +**hostname** + hostname from the message + +**source** + alias for HOSTNAME + +**fromhost** + hostname of the system the message was received from (in a relay chain, + this is the system immediately in front of us and not necessarily the + original sender). This is a DNS-resolved name, except if that is not + possible or DNS resolution has been disabled. + +**fromhost-ip** + The same as fromhost, but always as an IP address. Local inputs (like + imklog) use 127.0.0.1 in this property. + +**syslogtag** + TAG from the message + +**programname** + the "static" part of the tag, as defined by BSD syslogd. For example, + when TAG is "named[12345]", programname is "named". + + Precisely, the programname is terminated by either (whichever occurs first): + + - end of tag + - nonprintable character + - ':' + - '[' + - '/' + + The above definition has been taken from the FreeBSD syslogd sources. + + Please note that some applications include slashes in the static part + of the tag, e.g. "app/foo[1234]". In this case, programname is "app". + If they store an absolute path name like in "/app/foo[1234]", programname + will become empty (""). If you need to actually store slashes as + part of the programname, you can use the global option + + global(parser.permitSlashInProgramName="on") + + to permit this. Then, a syslogtag of "/app/foo[1234]" will result in + programname being "/app/foo". Note: this option is available starting at + rsyslogd version 8.25.0. + +**pri** + PRI part of the message - undecoded (single value) + +**pri-text** + the PRI part of the message in a textual form with the numerical PRI + appended in brackets (e.g. "local0.err<133>") + +**iut** + the monitorware InfoUnitType - used when talking to a + `MonitorWare <https://www.monitorware.com>`_ backend (also for + `Adiscon LogAnalyzer <https://loganalyzer.adiscon.com/>`_) + +**syslogfacility** + the facility from the message - in numerical form + +**syslogfacility-text** + the facility from the message - in text form + +**syslogseverity** + severity from the message - in numerical form + +**syslogseverity-text** + severity from the message - in text form + +**syslogpriority** + an alias for syslogseverity - included for historical reasons (be + careful: it still is the severity, not PRI!) + +**syslogpriority-text** + an alias for syslogseverity-text + +**timegenerated** + timestamp when the message was RECEIVED. Always in high resolution + +**timereported** + timestamp from the message. Resolution depends on what was provided in + the message (in most cases, only seconds) + +**timestamp** + alias for timereported + +**protocol-version** + The contents of the PROTOCOL-VERSION field from IETF draft + draft-ietf-syslog-protocol + +**structured-data** + The contents of the STRUCTURED-DATA field from IETF draft + draft-ietf-syslog-protocol + +**app-name** + The contents of the APP-NAME field from IETF draft + draft-ietf-syslog-protocol + +**procid** + The contents of the PROCID field from IETF draft + draft-ietf-syslog-protocol + +**msgid** + The contents of the MSGID field from IETF draft + draft-ietf-syslog-protocol + +**inputname** + The name of the input module that generated the message (e.g. + "imuxsock", "imudp"). Note that not all modules necessarily provide this + property. If not provided, it is an empty string. Also note that the + input module may provide any value of its liking. Most importantly, it + is **not** necessarily the module input name. Internal sources can also + provide inputnames. Currently, "rsyslogd" is defined as inputname for + messages internally generated by rsyslogd, for example startup and + shutdown and error messages. This property is considered useful when + trying to filter messages based on where they originated - e.g. locally + generated messages ("rsyslogd", "imuxsock", "imklog") should go to a + different place than messages generated somewhere else. + +**uuid** + + *Only Available if rsyslog is build with --enable-uuid* + + A UUID for the message. It is not present by default, but will be created + on first read of the uuid property. Thereafter, in the local rsyslog + instance, it will always be the same value. This is also true if rsyslog + is restarted and messages stayed in an on-disk queue. + + Note well: the UUID is **not** automatically transmitted to remote + syslog servers when forwarding. If that is needed, a special template + needs to be created that contains the uuid. Likewise, the receiver must + parse that UUID from that template. + + The uuid property is most useful if you would like to track a single + message across multiple local destination. An example is messages being + written to a database as well as to local files. + +**jsonmesg** + + *Available since rsyslog 8.3.0* + + The whole message object as JSON representation. Note that the JSON + string will *not* include an LF and it will contain *all other message + properties* specified here as respective JSON containers. It also includes + all message variables in the "$!" subtree (this may be null if none are + present). + + This property is primarily meant as an interface to other systems and + tools that want access to the full property set (namely external + plugins). Note that it contains the same data items potentially multiple + times. For example, parts of the syslog tag will by contained in the + rawmsg, syslogtag, and programname properties. As such, this property + has some additional overhead. Thus, it is suggested to be used only + when there is actual need for it. + +System Properties +----------------- +These properties are provided by the rsyslog core engine. They are **not** +related to the message. All system properties start with a dollar-sign. + +Special care needs to be taken in regard to time-related system variables: + +* ``timereported`` contains the timestamp that is contained within the + message header. Ideally, it resembles the time when the message was + created at the original sender. + Depending on how long the message was in the relay chain, this + can be quite old. +* ``timegenerated`` contains the timestamp when the message was received + by the local system. Here "received" actually means the point in time + when the message was handed over from the OS to rsyslog's reception + buffers, but before any actual processing takes place. This also means + a message is "received" before it is placed into any queue. Note that + depending on the input, some minimal processing like extraction of the + actual message content from the receive buffer can happen. If multiple + messages are received via the same receive buffer (a common scenario + for example with TCP-based syslog), they bear the same ``timegenerated`` + stamp because they actually were received at the same time. +* ``$now`` is **not** from the message. It is the system time when the + message is being **processed**. There is always a small difference + between ``timegenerated`` and ``$now`` because processing always + happens after reception. If the message is sitting inside a queue + on the local system, the time difference between the two can be some + seconds (e.g. due to a message burst and in-memory queueing) up to + several hours in extreme cases where a message is sitting inside a + disk queue (e.g. due to a database outage). The ``timereported`` + property is usually older than ``timegenerated``, but may be totally + different due to differences in time and time zone configuration + between systems. + +The following system properties exist: + +**$bom** + The UTF-8 encoded Unicode byte-order mask (BOM). This may be useful in + templates for RFC5424 support, when the character set is know to be + Unicode. + +**$myhostname** + The name of the current host as it knows itself (probably useful for + filtering in a generic way) + +Time-Related System Properties +.............................. + +All of these system properties exist in a local time variant (e.g. \$now) +and a variant that emits UTC (e.g. \$now-utc). The UTC variant is always +available by appending "-utc". Note that within a single template, only +the localtime or UTC variant should be used. While it is possible to mix +both variants within a single template, it is **not** guaranteed that +they will provide exactly the same time. The technical reason is that +rsyslog needs to re-query system time when the variant is changed. Because +of this, we strongly recommend not mixing both variants in the same +template. + +Note that use in different templates will generate a consistent timestamp +within each template. However, as $now always provides local system time +at time of using it, time may advance and consequently different templates +may have different time stamp. To avoid this, use *timegenerated* instead. + +**$now** + The current date stamp in the format YYYY-MM-DD + +**$year** + The current year (4-digit) + +**$month** + The current month (2-digit) + +**$day** + The current day of the month (2-digit) + +**$wday** + The current week day as defined by 'gmtime()'. 0=Sunday, ..., 6=Saturday + +**$hour** + The current hour in military (24 hour) time (2-digit) + +**$hhour** + The current half hour we are in. From minute 0 to 29, this is always 0 + while from 30 to 59 it is always 1. + +**$qhour** + The current quarter hour we are in. Much like $HHOUR, but values range + from 0 to 3 (for the four quarter hours that are in each hour) + +**$minute** + The current minute (2-digit) + +**$now-unixtimestamp** + The current time as a unix timestamp (seconds since epoch). This actually + is a monotonically increasing counter and as such can also be used for any + other use cases that require such counters. This is an example of how + to use it for rate-limiting:: + + # Get Unix timestamp of current message + set $.tnow = $$now-unixtimestamp + + # Rate limit info to 5 every 60 seconds + if ($!severity == 6 and $!facility == 17) then { + if (($.tnow - $/trate) > 60) then { + # 5 seconds window expired, allow more messages + set $/trate = $.tnow; + set $/ratecount = 0; + } + if ($/ratecount > 5) then { + # discard message + stop + } else { + set $/ratecount = $/ratecount + 1; + } + } + + NOTE: by definition, there is no "UTC equivalent" of the + $now-unixtimestamp property. diff --git a/source/configuration/property_replacer.rst b/source/configuration/property_replacer.rst new file mode 100644 index 0000000..3d99f5f --- /dev/null +++ b/source/configuration/property_replacer.rst @@ -0,0 +1,374 @@ +The Property Replacer +===================== + +**The property replacer is a core component in rsyslogd's** `string template +system <templates.html>`_. A syslog message has a number of well-defined properties. +Each of these properties can be accessed **and** manipulated by +the property replacer. With it, it is easy to use only part of a +property value or manipulate the value, e.g. by converting all +characters to lower case. + +Accessing Properties +-------------------- + +Syslog message properties are used inside templates. They are accessed +by putting them between percent signs. Properties can be modified by the +property replacer. The full syntax is as follows: + +:: + + %property:fromChar:toChar:options% + +Available Properties +^^^^^^^^^^^^^^^^^^^^ + +The property replacer can use all :doc:`rsyslog properties <properties>`. + +Character Positions +^^^^^^^^^^^^^^^^^^^^ + +**FromChar** and **toChar** are used to build substrings. They +specify the offset within the string that should be copied. Offset +counting starts at 1, so if you need to obtain the first 2 characters of +the message text, you can use this syntax: "%msg:1:2%". If you do not +wish to specify from and to, but you want to specify options, you still +need to include the colons. For example, if you would like to convert +the full message text to lower case, use "%msg:::lowercase%". If you +would like to extract from a position until the end of the string, you +can place a dollar-sign ("$") in toChar (e.g. %msg:10:$%, which will +extract from position 10 to the end of the string). + +There is also support for **regular expressions**. To use them, you need +to place a "R" into FromChar. This tells rsyslog that a regular +expression instead of position-based extraction is desired. The actual +regular expression must then be provided in toChar. The regular +expression **must** be followed by the string "--end". It denotes the +end of the regular expression and will not become part of it. If you are +using regular expressions, the property replacer will return the part of +the property text that matches the regular expression. An example for a +property replacer sequence with a regular expression is: +"%msg:R:.\*Sev:. \\(.\*\\) \\[.\*--end%" + +It is possible to specify some parameters after the "R". These are +comma-separated. They are: + +R,<regexp-type>,<submatch>,<:doc:`nomatch <nomatch>`\ >,<match-number> + +regexp-type is either "BRE" for Posix basic regular expressions or "ERE" +for extended ones. The string must be given in upper case. The default +is "BRE" to be consistent with earlier versions of rsyslog that did not +support ERE. The submatch identifies the submatch to be used with the +result. A single digit is supported. Match 0 is the full match, while 1 +to 9 are the actual submatches. The match-number identifies which match +to use, if the expression occurs more than once inside the string. +Please note that the first match is number 0, the second 1 and so on. Up +to 10 matches (up to number 9) are supported. Please note that it would +be more natural to have the match-number in front of submatch, but this +would break backward-compatibility. So the match-number must be +specified after "nomatch". + +:doc:`nomatch <nomatch>` specifies what should be used in +case no match is found. + +The following is a sample of an ERE expression that takes the first +submatch from the message string and replaces the expression with the +full field if no match is found: + +:: + +%msg:R,ERE,1,FIELD:for (vlan[0-9]\*):--end% + +and this takes the first submatch of the second match of said +expression: + +:: + +%msg:R,ERE,1,FIELD,1:for (vlan[0-9]\*):--end% + +**Please note: there is also a** `rsyslog regular expression +checker/generator <http://www.rsyslog.com/tool-regex>`_ **online tool +available.** With that tool, you can check your regular expressions and +also generate a valid property replacer sequence. Usage of this tool is +recommended. Depending on the version offered, the tool may not cover +all subtleties that can be done with the property replacer. It +concentrates on the most often used cases. So it is still useful to +hand-craft expressions for demanding environments. + +**Also, extraction can be done based on so-called "fields"**. To do so, +place a "F" into FromChar. A field in its current definition is anything +that is delimited by a delimiter character. The delimiter by default is +TAB (US-ASCII value 9). However, if can be changed to any other US-ASCII +character by specifying a comma and the **decimal** US-ASCII value of +the delimiter immediately after the "F". For example, to use comma (",") +as a delimiter, use this field specifier: "F,44". If your syslog data +is delimited, this is a quicker way to extract than via regular +expressions (actually, a *much* quicker way). Field counting starts at +1. Field zero is accepted, but will always lead to a "field not found" +error. The same happens if a field number higher than the number of +fields in the property is requested. The field number must be placed in +the "ToChar" parameter. An example where the 3rd field (delimited by +TAB) from the msg property is extracted is as follows: "%msg:F:3%". The +same example with semicolon as delimiter is "%msg:F,59:3%". + +The use of fields does not permit to select substrings, what is rather +unfortunate. To solve this issue, starting with 6.3.9, fromPos and toPos +can be specified for strings as well. However, the syntax is quite ugly, +but it was the only way to integrate this functionality into the +already-existing system. To do so, use ",fromPos" and ",toPos" during +field extraction. Let's assume you want to extract the substring from +position 5 to 9 in the previous example. Then, the syntax is as follows: +"%msg:F,59,5:3,9%". As you can see, "F,59" means field-mode, with +semicolon delimiter and ",5" means starting at position 5. Then "3,9" +means field 3 and string extraction to position 9. + +Please note that the special characters "F" and "R" are case-sensitive. +Only upper case works, lower case will return an error. There are no +white spaces permitted inside the sequence (that will lead to error +messages and will NOT provide the intended result). + +Each occurrence of the field delimiter starts a new field. However, if +you add a plus sign ("+") after the field delimiter, multiple +delimiters, one immediately after the others, are treated as separate +fields. This can be useful in cases where the syslog message contains +such sequences. A frequent case may be with code that is written as +follows: + +```` + +:: + + int n, m; + ... + syslog(LOG_ERR, "%d test %6d", n, m); + +This will result into things like this in syslog messages: "1 +test 2", "1 test 23", "1 test 234567" + +As you can see, the fields are delimited by space characters, but their +exact number is unknown. They can properly be extracted as follows: + +:: + + "%msg:F,32:2%" to "%msg:F,32+:2%". + +This feature was suggested by Zhuang Yuyao and implemented by him. It is +modeled after perl compatible regular expressions. + +Property Options +^^^^^^^^^^^^^^^^ + +**Property options** are case-insensitive. Currently, the following +options are defined: + +**uppercase** + convert property to uppercase only + +**lowercase** + convert property text to lowercase only + +**fixed-width** + changes behaviour of toChar so that it pads the source string with spaces + up to the value of toChar if the source string is shorter. + *This feature was introduced in rsyslog 8.13.0* + +**json** + encode the value so that it can be used inside a JSON field. This means + that several characters (according to the JSON spec) are being escaped, for + example US-ASCII LF is replaced by "\\n". + The json option cannot be used together with either jsonf or csv options. + +**jsonf**\[:outname\] + (available in 6.3.9+) + This signifies that the property should be expressed as a JSON field. + That means not only the property is written, but rather a complete JSON field in + the format + + ``"fieldname"="value"`` + + where "fieldname" is given in the *outname* property (or the property name + if none was assigned) and value is the end result of property replacer operation. + Note that value supports all property replacer options, like substrings, case + conversion and the like. Values are properly JSON-escaped, however field names are + (currently) not, so it is expected that proper field names are configured. + The jsonf option cannot be used together with either json or csv options. + + For more information you can read `this article from Rainer's blog + <https://rainer.gerhards.net/2012/04/rsyslog-templates-json.html>`_. + +**csv** + formats the resulting field (after all modifications) in CSV format as + specified in `RFC 4180 <http://www.ietf.org/rfc/rfc4180.txt>`_. Rsyslog + will always use double quotes. Note that in order to have full + CSV-formatted text, you need to define a proper template. An example is + this one: + $template csvline,"%syslogtag:::csv%,%msg:::csv%" + Most importantly, you need to provide the commas between the fields + inside the template. + *This feature was introduced in rsyslog 4.1.6.* + +**drop-last-lf** + The last LF in the message (if any), is dropped. Especially useful for + PIX. + +**date-utc** + convert data to UTC prior to outputting it (available since 8.18.0) + +**date-mysql** + format as mysql date + +**date-rfc3164** + format as RFC 3164 date + +**date-rfc3164-buggyday** + similar to date-rfc3164, but emulates a common coding error: RFC 3164 + demands that a space is written for single-digit days. With this option, + a zero is written instead. This format seems to be used by syslog-ng and + the date-rfc3164-buggyday option can be used in migration scenarios + where otherwise lots of scripts would need to be adjusted. It is + recommended *not* to use this option when forwarding to remote hosts - + they may treat the date as invalid (especially when parsing strictly + according to RFC 3164). + + *This feature was introduced in rsyslog 4.6.2 and v4 versions above and + 5.5.3 and all versions above.* + +**date-rfc3339** + format as RFC 3339 date + +**date-unixtimestamp** + Format as a unix timestamp (seconds since epoch) + +**date-year** + just the year part (4-digit) of a timestamp + +**date-month** + just the month part (2-digit) of a timestamp + +**date-day** + just the day part (2-digit) of a timestamp + +**date-hour** + just the hour part (2-digit, 24-hour clock) of a timestamp + +**date-minute** + just the minute part (2-digit) of a timestamp + +**date-second** + just the second part (2-digit) of a timestamp + +**date-subseconds** + just the subseconds of a timestamp (always 0 for a low precision + timestamp) + +**date-tzoffshour** + just the timezone offset hour part (2-digit) of a timestamp + +**date-tzoffsmin** + just the timezone offset minute part (2-digit) of a timestamp. Note + that this is usually 0, but there are some time zones that have + offsets which are not hourly-granular. If so, this is the minute + offset. + +**date-tzoffsdirection** + just the timezone offset direction part of a timestamp. This + specifies if the offsets needs to be added ("+") or subtracted ("-") + to the timestamp in order to get UTC. + +**date-ordinal** + returns the ordinal for the given day, e.g. it is 2 for January, 2nd + +**date-iso-week** and **date-iso-week-year** + return the ISO week number adn week-numbering year, which should be used together. See `ISO week date <https://en.wikipedia.org/wiki/ISO_week_date>`_ for more details + +**date-week** + returns the week number + +**date-wday** + just the weekday number of the timstamp. This is a single digit, + with 0=Sunday, 1=Monday, ..., 6=Saturday. + +**date-wdayname** + just the abbreviated english name of the weekday (e.g. "Mon", "Sat") of + the timestamp. + +**escape-cc** + replace control characters (ASCII value 127 and values less then 32) + with an escape sequence. The sequence is "#<charval>" where charval is + the 3-digit decimal value of the control character. For example, a + tabulator would be replaced by "#009". + Note: using this option requires that + `$EscapeControlCharactersOnReceive <rsconf1_escapecontrolcharactersonreceive.html>`_ + is set to off. + +**space-cc** + replace control characters by spaces + Note: using this option requires that + `$EscapeControlCharactersOnReceive <rsconf1_escapecontrolcharactersonreceive.html>`_ + is set to off. + +**drop-cc** + drop control characters - the resulting string will neither contain + control characters, escape sequences nor any other replacement character + like space. + Note: using this option requires that + `$EscapeControlCharactersOnReceive <rsconf1_escapecontrolcharactersonreceive.html>`_ + is set to off. + +**compressspace** + compresses multiple spaces (US-ASCII SP character) inside the + string to a single one. This compression happens at a very late + stage in processing. Most importantly, it happens after substring + extraction, so the **FromChar** and **ToChar** positions are **NOT** + affected by this option. (available since v8.18.0) + +**sp-if-no-1st-sp** + This option looks scary and should probably not be used by a user. For + any field given, it returns either a single space character or no + character at all. Field content is never returned. A space is returned + if (and only if) the first character of the field's content is NOT a + space. This option is kind of a hack to solve a problem rooted in RFC + 3164: 3164 specifies no delimiter between the syslog tag sequence and + the actual message text. Almost all implementation in fact delimit the + two by a space. As of RFC 3164, this space is part of the message text + itself. This leads to a problem when building the message (e.g. when + writing to disk or forwarding). Should a delimiting space be included if + the message does not start with one? If not, the tag is immediately + followed by another non-space character, which can lead some log parsers + to misinterpret what is the tag and what the message. The problem + finally surfaced when the klog module was restructured and the tag + correctly written. It exists with other message sources, too. The + solution was the introduction of this special property replacer option. + Now, the default template can contain a conditional space, which exists + only if the message does not start with one. While this does not solve + all issues, it should work good enough in the far majority of all cases. + If you read this text and have no idea of what it is talking about - + relax: this is a good indication you will never need this option. Simply + forget about it ;) + +**secpath-drop** + Drops slashes inside the field (e.g. "a/b" becomes "ab"). Useful for + secure pathname generation (with dynafiles). + +**secpath-replace** + Replace slashes inside the field by an underscore. (e.g. "a/b" becomes + "a\_b"). Useful for secure pathname generation (with dynafiles). + +To use multiple options, simply place them one after each other with a +comma delimiting them. For example "escape-cc,sp-if-no-1st-sp". If you +use conflicting options together, the last one will override the +previous one. For example, using "escape-cc,drop-cc" will use drop-cc +and "drop-cc,escape-cc" will use escape-cc mode. + +Further Links +------------- + +- Article on ":doc:`Recording the Priority of Syslog + Messages <../tutorials/recording_pri>`" (describes use of + templates to record severity and facility of a message) +- `Configuration file syntax <rsyslog_conf.html>`_, this is where you + actually use the property replacer. + +.. toctree:: + :maxdepth: 2 + + nomatch diff --git a/source/configuration/rsyslog-example.conf b/source/configuration/rsyslog-example.conf new file mode 100644 index 0000000..a3ec2f1 --- /dev/null +++ b/source/configuration/rsyslog-example.conf @@ -0,0 +1,163 @@ +# A commented quick reference and sample configuration +# WARNING: This is not a manual, the full manual of rsyslog configuration is in +# rsyslog.conf (5) manpage +# +# "$" starts lines that contain new directives. The full list of directives +# can be found in /usr/share/doc/rsyslog-1.19.6/doc/rsyslog_conf.html or online +# at http://www.rsyslog.com/doc if you do not have (or find) a local copy. +# +# Set syslogd options + +# Some global directives +# ---------------------- + +# $AllowedSender - specifies which remote systems are allowed to send syslog messages to rsyslogd +# -------------- +$AllowedSender UDP, 127.0.0.1, 192.0.2.0/24, [::1]/128, *.example.net, somehost.example.com + +# $UMASK - specifies the rsyslogd processes' umask +# ------ +$umask 0000 + +# $FileGroup - Set the group for dynaFiles newly created +# ---------- +$FileGroup loggroup + +# $FileOwner - Set the file owner for dynaFiles newly created. +# ---------- +$FileOwner loguser + +# $IncludeConfig - include other files into the main configuration file +# -------------- +$IncludeConfig /etc/some-included-file.conf # one file +$IncludeConfig /etc/rsyslog.d/ # whole directory (must contain the final slash) + +# $ModLoad - Dynamically loads a plug-in and activates it +# -------- +$ModLoad ommysql # load MySQL functionality +$ModLoad /rsyslog/modules/somemodule.so # load a module via absolute path + + + +# Templates +# --------- + +# Templates allow to specify any format a user might want. +# They MUST be defined BEFORE they are used. + +# A template consists of a template directive, a name, the actual template text +# and optional options. A sample is: +# +$template MyTemplateName,"\7Text %property% some more text\n", + +# where: +# * $template - tells rsyslog that this line contains a template. +# * MyTemplateName - template name. All other config lines refer to this name. +# * "\7Text %property% some more text\n" - templage text + +# The backslash is an escape character, i.e. \7 rings the bell, \n is a new line. +# To escape: +# % = \% +# \ = \\ + +# Template options are case-insensitive. Currently defined are: +# sql format the string suitable for a SQL statement. This will replace single +# quotes ("'") by two single quotes ("''") to prevent the SQL injection +# (NO_BACKSLASH_ESCAPES turned off) +# stdsql - format the string suitable for a SQL statement that is to +# be sent to a standards-compliant sql server. +# (NO_BACKSLASH_ESCAPES turned on) + + + +# Properties inside templates +# --------------------------- + +# Properties can be modified by the property replacer. They are accessed +# inside the template by putting them between percent signs. The full syntax is as follows: + +# %propname:fromChar:toChar:options% + +# FromChar and toChar are used to build substrings. +# If you need to obtain the first 2 characters of the +# message text, you can use this syntax: +"%msg:1:2%". +# If you do not whish to specify from and to, but you want to +# specify options, you still need to include the colons. + +# For example, to convert the full message text to lower case only, use +# "%msg:::lowercase%". + +# The full list of property options can be found in rsyslog.conf(5) manpage + + + +# Samples of template definitions +# ------------------------------- + +# A template that resambles traditional syslogd file output: +$template TraditionalFormat,"%timegenerated% %HOSTNAME% %syslogtag%%msg:::drop-last-lf%\n" + +# A more verbose template: +$template precise,"%syslogpriority%,%syslogfacility%,%timegenerated::fulltime%,%HOSTNAME%,%syslogtag%,%msg%\n" + +# A template that resembles RFC 3164 on-the-wire format: +# (yes, there is NO space betwen syslogtag and msg! that's important!) +$template RFC3164fmt,"<%PRI%>%TIMESTAMP% %HOSTNAME% %syslogtag%%msg%" + +# a template resembling traditional wallmessage format: +$template wallmsg,"\r\n\7Message from syslogd@%HOSTNAME% at %timegenerated% ...\r\n %syslogtag%%msg%\n\r" + +# The template below emulates winsyslog format, but we need to check the time +# stamps used. It is also a good sampleof the property replacer in action. +$template WinSyslogFmt,"%HOSTNAME%,%timegenerated:1:10:date-rfc3339%,%timegenerated:12:19:date-rfc3339%,%timegenerated:1:10:date-rfc3339%,%timegenerated:12:19:date-rfc3339%,%syslogfacility%,%syslogpriority%,%syslogtag%%msg%\n" + +# A template used for database writing (notice it *is* an actual +# sql-statement): +$template dbFormat,"insert into SystemEvents (Message, Facility,FromHost, Priority, DeviceReportedTime, ReceivedAt, InfoUnitID, SysLogTag) values ('%msg%', %syslogfacility%, '%HOSTNAME%',%syslogpriority%, '%timereported:::date-mysql%', '%timegenerated:::date-mysql%', %iut%, '%syslogtag%')",sql + + + +# Samples of rules +# ---------------- +# Regular file +# ------------ +*.* /var/log/traditionalfile.log;TraditionalFormat # log to a file in the traditional format + +# Forwarding to remote machine +# ---------------------------- +*.* @172.19.2.16 # udp (standard for syslog) +*.* @@172.19.2.17 # tcp + +# Database action +# --------------- +# (you must have rsyslog-mysql package installed) +# !!! Don't forget to set permission of rsyslog.conf to 600 !!! +*.* >hostname,dbname,userid,password # (default Monitorware schema, can be created by /usr/share/doc/rsyslog-mysql-1.19.6/createDB.sql) + +# And this one uses the template defined above: +*.* >hostname,dbname,userid,password;dbFormat + +# Program to execute +# ------------------ +*.* ^alsaunmute # set default volume to soundcard + +# Filter using regex +# ------------------ +# if the user logges word rulez or rulezz or rulezzz or..., then we will shut down his pc +# (note, that + have to be double backslashed...) +:msg, regex, "rulez\\+" ^poweroff + +# A more complex example +# ---------------------- +$template bla_logged,"%timegenerated% the BLA was logged" +:msg, contains, "bla" ^logger;bla_logged + +# Pipes +# ----- +# first we need to create pipe by # mkfifo /a_big_pipe +*.* |/a_big_pipe + +# Discarding +# ---------- +*.* ~ # discards everything diff --git a/source/configuration/rsyslog_statistic_counter.rst b/source/configuration/rsyslog_statistic_counter.rst new file mode 100644 index 0000000..231b32c --- /dev/null +++ b/source/configuration/rsyslog_statistic_counter.rst @@ -0,0 +1,83 @@ +rsyslog statistic counter +========================= + +Rsyslog supports statistic counters via the :doc:`impstats <modules/impstats>` module. +It is important to know that impstats and friends only provides an infrastructure +where core components and plugins can register statistics counter. This FAQ entry +tries to describe all counters available, but please keep in mind that there may exist +that we do not know about. + +When interpreting rsyslog statistics, please keep in mind that statistics records are +processed as regular syslog messages. As such, the statistics messages themselves +increment counters when they are emitted via the regular syslog stream, which is the +default (and so counters keep slowly increasing even if there is absolutely no other +traffic). Also keep in mind that a busy rsyslog system is very dynamic. Most +importantly, this means that the counters may not be 100% consistent, but some slight +differences may exist. Avoiding such inconsistencies would be possible only at the +price of a very tight locking discipline, which would cause serious performance +bottlenecks. Thus, this is not done. Finally, though extremely unlikely, some counters +may experience an overflow and restart at 0 for that reasons. However, most counters +are 64-bit, so this is extremely unlikely. Those which are not 64 bit are typically +taken from some internal data structure that uses lower bits for performance reasons +and guards against overflow. + +The listing starts with the core component or plugin that creates the counters and +than specifies various counters that exist for the sub-entities. The listing below is +extended as new counters are added. Some counters probably do not exist in older +releases of rsyslog. + +Queue +----- + +For each queue inside the system its own set of statistics counters is created. +If there are multiple action (or main) queues, this can become a rather lengthy list. +The stats record begins with the queue name (e.g. "main Q" for the main queue; +ruleset queues have the name of the ruleset they are associated to, action queues +the name of the action). + +- **size** - currently active messages in queue + +- **enqueued** - total number of messages enqueued into this queue since startup + +- **maxsize** - maximum number of active messages the queue ever held + +- **full** - number of times the queue was actually full and could not accept additional messages + +- **discarded.full** - number of messages discarded because the queue was full + +- **discarded.nf** - number of messages discarded because the queue was nearly full. Starting at this point, messages of lower-than-configured severity are discarded to save space for higher severity ones. + +Actions +------- + +- **processed** - total number of messages processed by this action. This includes those messages that failed actual execution (so it is a total count of messages ever seen, but not necessarily successfully processed) + +- **failed** - total number of messages that failed during processing. These are actually lost if they have not been processed by some other action. Most importantly in a failover chain the messages are flagged as "failed" in the failing actions even though they are forwarded to the failover action (the failover action’s "processed" count should equal to failing actions "fail" count in this scenario)a + +- **suspended** - (7.5.8+) – total number of times this action suspended itself. Note that this counts the number of times the action transitioned from active to suspended state. The counter is no indication of how long the action was suspended or how often it was retried. This is intentional, as the counter as it currently is permits to tell how often the action ran into a failure condition. + +- **suspended.duration** - (7.5.8+) – the total number of seconds this action was disabled. Note that the second count is incremented as soon as the action is suspended for another interval. As such, the time may be higher than it should be at the reporting point of time. If the pstats interval is shorter than the suspension timeout, the same suspended.duration value may be reported for successive pstats outputs. For a long-running system, this is considered a minimal difference. In general, note that this setting is not totally accurate, especially when running with multiple worker threads. In rsyslog v8, this is the total suspended time for all worker instances of this action. + +- **resumed** - (7.5.8+) – total number of times this action resumed itself. A resumption occurs after the action has detected that a failure condition does no longer exist. + +Plugins +------- + +:doc:`imuxsock <modules/imuxsock>` + +:doc:`imudp <modules/imudp>` + +:doc:`imtcp <modules/imtcp>` + +:doc:`imptcp <modules/imptcp>` + +:doc:`imrelp <modules/imrelp>` + +:doc:`impstats <modules/impstats>` + +:doc:`omfile <modules/omfile>` + +:doc:`omelasticsearch <modules/omelasticsearch>` + +:doc:`omkafka <modules/omkafka>` + diff --git a/source/configuration/ruleset/index.rst b/source/configuration/ruleset/index.rst new file mode 100644 index 0000000..429e1a2 --- /dev/null +++ b/source/configuration/ruleset/index.rst @@ -0,0 +1,20 @@ +Ruleset-Specific Legacy Configuration Statements +================================================ +These statements can be used to set ruleset parameters. To set +these parameters, first use *$Ruleset*, **then** use the other +configuration directives. Please keep in mind +that each ruleset has a *main* queue. To specify parameter for these +ruleset (main) queues, use the main queue configuration directives. + +.. toctree:: + :glob: + + *rule* + +- **$Ruleset** *name* - starts a new ruleset or switches back to one + already defined. All following actions belong to that new rule set. + the *name* does not yet exist, it is created. To switch back to + rsyslog's default ruleset, specify "RSYSLOG\_DefaultRuleset") as the + name. All following actions belong to that new rule set. It is + advised to also read our paper on + :doc:`using multiple rule sets in rsyslog <../../concepts/multi_ruleset>`. diff --git a/source/configuration/ruleset/rsconf1_rulesetcreatemainqueue.rst b/source/configuration/ruleset/rsconf1_rulesetcreatemainqueue.rst new file mode 100644 index 0000000..16f73a6 --- /dev/null +++ b/source/configuration/ruleset/rsconf1_rulesetcreatemainqueue.rst @@ -0,0 +1,91 @@ +`rsyslog.conf configuration directive <rsyslog_conf_global.html>`_ + +$RulesetCreateMainQueue +----------------------- + +**Type:** ruleset-specific configuration directive + +**Parameter Values:** boolean (on/off, yes/no) + +**Available since:** 5.3.5+ + +**Default:** off + +**Description:** + +Rulesets may use their own "main" message queue for message submission. +Specifying this directive, **inside a ruleset definition**, turns this +on. This is both a performance enhancement and also permits different +rulesets (and thus different inputs within the same rsyslogd instance) +to use different types of main message queues. + +The ruleset queue is created with the parameters that are specified for +the main message queue at the time the directive is given. If different +queue configurations are desired, different main message queue +directives must be used **in front of** the $RulesetCreateMainQueue +directive. Note that this directive may only be given once per ruleset. +If multiple statements are specified, only the first is used and for the +others error messages are emitted. + +Note that the final set of ruleset configuration directives specifies +the parameters for the default main message queue. + +To learn more about this feature, please be sure to read about +`multi-ruleset support in rsyslog <multi_ruleset.html>`_. + +**Caveats:** + +The configuration statement "$RulesetCreateMainQueue off" has no effect +at all. The capability to specify this is an artifact of the legacy +configuration language. + +**Example:** + +This example sets up a tcp server with three listeners. Each of these +three listener is bound to a specific ruleset. As a performance +optimization, the rulesets all receive their own private queue. The +result is that received messages can be independently processed. With +only a single main message queue, we would have some lock contention +between the messages. This does not happen here. Note that in this +example, we use different processing. Of course, all messages could also +have been processed in the same way ($IncludeConfig may be useful in +that case!). + +:: + + $ModLoad imtcp + # at first, this is a copy of the unmodified rsyslog.conf + #define rulesets first + $RuleSet remote10514 + $RulesetCreateMainQueue on # create ruleset-specific queue + *.* /var/log/remote10514 + + $RuleSet remote10515 + $RulesetCreateMainQueue on # create ruleset-specific queue + *.* /var/log/remote10515 + + $RuleSet remote10516 + $RulesetCreateMainQueue on # create ruleset-specific queue + mail.* /var/log/mail10516 + & ~ + # note that the discard-action will prevent this messag from + # being written to the remote10516 file - as usual... + *.* /var/log/remote10516 + + # and now define listeners bound to the relevant ruleset + $InputTCPServerBindRuleset remote10514 + $InputTCPServerRun 10514 + + $InputTCPServerBindRuleset remote10515 + $InputTCPServerRun 10515 + + $InputTCPServerBindRuleset remote10516 + $InputTCPServerRun 10516 + + +Note the positions of the directives. With the legacy language, +position is very important. It is highly suggested to use +the *ruleset()* object in RainerScript config language if you intend +to use ruleset queues. The configuration is much more straightforward in +that language and less error-prone. + diff --git a/source/configuration/ruleset/rsconf1_rulesetparser.rst b/source/configuration/ruleset/rsconf1_rulesetparser.rst new file mode 100644 index 0000000..0fb9925 --- /dev/null +++ b/source/configuration/ruleset/rsconf1_rulesetparser.rst @@ -0,0 +1,127 @@ +$RulesetParser +-------------- + +**Type:** ruleset-specific configuration directive + +**Parameter Values:** string + +**Available since:** 5.3.4+ + +**Default:** rsyslog.rfc5424 followed by rsyslog.rfc3164 + +**Description:** + +This directive permits to specify which `message +parsers <../../concepts/messageparser.html>`_ should be used for the ruleset in +question. It no ruleset is explicitly specified, the default ruleset is +used. Message parsers are contained in (loadable) parser modules with +the most common cases (RFC3164 and RFC5424) being build-in into +rsyslogd. + +When this directive is specified the first time for a ruleset, it will +not only add the parser to the ruleset's parser chain, it will also wipe +out the default parser chain. So if you need to have them in addition to +the custom parser, you need to specify those as well. + +Order of directives is important. Parsers are tried one after another, +in the order they are specified inside the config. As soon as a parser +is able to parse the message, it will do so and no other parsers will be +executed. If no matching parser can be found, the message will be +discarded and a warning message be issued (but only for the first 1,000 +instances of this problem, to prevent message generation loops). + +Note that the rfc3164 parser will **always** be able to parse a message +- it may just not be the format that you like. This has two important +implications: 1) always place that parser at the END of the parser list, +or the other parsers after it will never be tried and 2) if you would +like to make sure no message is lost, placing the rfc3164 parser at the +end of the parser list ensures that. + +Multiple parser modules are very useful if you have various devices that +emit messages that are malformed in various ways. The route to take then +is + +- make sure you find a custom parser for that device; if there is no + one, you may consider writing one yourself (it is not that hard) or + getting one written as part of `Adiscon's professional services for + rsyslog <http://www.rsyslog.com/professional-services>`_. +- load your custom parsers via $ModLoad +- create a ruleset for each malformed format; assign the custom parser + to it +- create a specific listening port for all devices that emit the same + malformed format +- bind the listener to the ruleset with the required parser + +Note that it may be cumbersome to add all rules to all rulesets. To +avoid this, you can either use $Include or `omruleset <omruleset.html>`_ +(what probably provides the best solution). + +More information about rulesets in general can be found in +:doc:`multi-ruleset support in rsyslog <../../concepts/multi_ruleset>`. + +**Caveats:** + +currently none known + +**Example:** + +This example assumes there are two devices emitting malformed messages +via UDP. We have two custom parsers for them, named "device1.parser" and +"device2.parser". In addition to that, we have a number of other devices +sending well-formed messages, also via UDP. + +The solution is to listen for data from the two devices on two special +ports (10514 and 10515 in this example), create a ruleset for each and +assign the custom parsers to them. The rest of the messages are received +via port 514 using the regular parsers. Processing shall be equal for +all messages. So we simply forward the malformed messages to the regular +queue once they are parsed (keep in mind that a message is never again +parsed once any parser properly processed it). + +:: + + $ModLoad imudp + $ModLoad pmdevice1 # load parser "device1.parser" for device 1 + $ModLoad pmdevice2 # load parser "device2.parser" for device 2 + + # define ruleset for the first device sending malformed data + $Ruleset maldev1 + $RulesetCreateMainQueue on # create ruleset-specific queue + $RulesetParser "device1.parser" # note: this deactivates the default parsers + # forward all messages to default ruleset: + $ActionOmrulesetRulesetName RSYSLOG\_DefaultRuleset + \*.\* :omruleset: + + # define ruleset for the second device sending malformed data + $Ruleset maldev2 $RulesetCreateMainQueue on # create ruleset-specific queue + $RulesetParser "device2.parser" # note: this deactivates the default parsers + # forward all messages to default ruleset: + $ActionOmrulesetRulesetName RSYSLOG\_DefaultRuleset + \*.\* :omruleset: + + # switch back to default ruleset + $Ruleset RSYSLOG\_DefaultRuleset + \*.\* /path/to/file + auth.info @authlogger.example.net + # whatever else you usually do... + + # now define the inputs and bind them to the rulesets + # first the default listener (utilizing the default ruleset) + $UDPServerRun 514 + + # now the one with the parser for device type 1: + $InputUDPServerBindRuleset maldev1 + $UDPServerRun 10514 + + # and finally the one for device type 2: + $InputUDPServerBindRuleset maldev2 + $UDPServerRun 10515 + +For an example of how multiple parser can be chained (and an actual use +case), please see the example section on the +`pmlastmsg <pmlastmsg.html>`_ parser module. + +Note the positions of the directives. With the current config language, +**sequence of statements is very important**. This is ugly, but +unfortunately the way it currently works. + diff --git a/source/configuration/sysklogd_format.rst b/source/configuration/sysklogd_format.rst new file mode 100644 index 0000000..3fd9b8a --- /dev/null +++ b/source/configuration/sysklogd_format.rst @@ -0,0 +1,311 @@ + +*************** +sysklogd format +*************** + +This is the format in use since the beginning of syslogging. It still +is an excellent choice to do very simple things. + +For more advanced things, use the |FmtAdvancedName| format. + +DESCRIPTION +=========== + +The syslog.conf file is the main configuration file for :manpage:`syslogd(8)` +which logs system messages on \*nix systems. This file specifies rules for +logging. For special features see the sysklogd(8) manpage. + +Every rule consists of two fields, a selector field and an action field. +These two fields are separated by one or more spaces or tabs. The selector +field specifies a pattern of facilities and priorities belonging to the +specified action. + +Lines starting with a hash mark ("#") and empty lines are ignored. + +This variant of syslogd is able to understand a slightly extended syntax +compared to the original BSD syslogd. One rule may be divided into several +lines if the leading line is terminated with an backslash ("\\"). + +SELECTORS +========= + +The selector field consists of two parts, a facility and a priority, separated +by a period ("."). Both parts are case insensitive and can also be specified +as decimal numbers corresponding to the definitions in +``/usr/include/syslog.h``. It is safer to use symbolic names rather than +decimal numbers. Both facilities and priorities are described in +:manpage:`syslog(3)`. The names mentioned below +correspond to the similar ``LOG_`` values in ``/usr/include/syslog.h``. + +The facility is one of the following keywords: auth, authpriv, cron, daemon, +ftp, kern, lpr, mail, mark, news, security (same as auth), syslog, user, uucp +and local0 through local7. The keyword security is deprecated and mark is only +for internal use and therefore should not be used in applications. The facility +specifies the subsystem that produced the message, e.g. all mail programs log +with the mail facility (LOG_MAIL) if they log using syslog. + +In most cases anyone can log to any facility, so we rely on convention for the +correct facility to be chosen. However, generally only the kernel can log to +the "kern" facility. This is because the implementation of ``openlog()`` and +``syslog()`` in glibc does not allow logging to the "kern" facility. Klogd +circumvents this restriction when logging to syslogd by reimplementing those +functions itself. + +The priority is one of the following keywords, in ascending order: debug, +info, notice, warning, warn (same as warning), err, error (same as err), crit, +alert, emerg, panic (same as emerg). The keywords warn, error and panic are +deprecated and should not be used anymore. The priority defines the severity of +the message. + +The behavior of the original BSD syslogd is that all messages of the specified +priority and higher are logged according to the given action. This +:manpage:`syslogd(8)` behaves the same, but has some extensions. + +In addition to the above mentioned names the :manpage:`syslogd(8)` understands +the following extensions: +An asterisk ("\*") stands for all facilities or all priorities, depending on +where it is used (before or after the period). The keyword none stands for no +priority of the given facility. + +Multiple facilities may be specified for a single priority pattern in one +statement using the comma (",") operator to separate the facilities. You may +specify as many facilities as you want. Please note that only the facility +part from such a statement is taken, a priority part would be ignored. + +Multiple selectors may be specified for a single action using the semicolon +(";") separator. Selectors are processed from left to right, with each selector +being able to overwrite preceding ones. Using this behavior you are able to +exclude some priorities from the pattern. + +This :manpage:`syslogd(8)` has a syntax extension to the original BSD source, +which makes its use more intuitive. You may precede every priority with an +equation sign ("=") to specify that syslogd should only refer to this single +priority and not this priority and all higher priorities. + +You may also precede the priority with an exclamation mark ("!") if you want +syslogd to ignore this priority and all higher priorities. You may even use +both, the exclamation mark and the equation sign if you want syslogd to ignore +only this single priority. If you use both extensions then the exclamation +mark must occur before the equation sign, just use it intuitively. + +ACTIONS +======= + +The action field of a rule describes the abstract term "logfile". A "logfile" +need not to be a real file, btw. The :manpage:`syslogd(8)` provides the +following actions. + +Regular File +------------ + +Typically messages are logged to real files. The filename is specified with an +absolute pathname. It may be specified as a file name relative to rsyslog's +working directory if the filename starts with "." or "..". However, this is +dangerous and should be avoided. + +Named Pipes +----------- + +This version of :manpage:`syslogd(8)` has support for logging output to named +pipes (fifos). A fifo or named pipe can be used as a destination for log +messages by prepending a pipe symbol ("|") to the name of the file. This is +handy for debugging. Note that the fifo must be created with the +:manpage:`mkfifo(1)` command before :manpage:`syslogd(8)` is started. + +Terminal and Console +-------------------- + +If the file you specified is a tty, special tty-handling is done, same with +``/dev/console``. + +Remote Machine +-------------- + +This :manpage:`syslogd(8)` provides full remote logging, i.e. is able to send +messages to a remote host running :manpage:`syslogd(8)` and to receive messages +from remote hosts. The remote host won't forward the message again, it will +just log them locally. To forward messages to another host, prepend the +hostname with the at sign ("@"). + +Using this feature you are able to collect all syslog messages on a central +host, if all other machines log remotely to that one. This reduces +administration needs. + +Using a named pipe log method, messages from remote hosts can be sent to a +log program. By reading log messages line by line such a program is able to +sort log messages by host name or program name on the central log host. This +way it is possible to split the log into separate files. + +List of Users +------------- + +Usually critical messages are also directed to "root" on that machine. You can +specify a list of users that ought to receive the log message on the terminal +by writing their usernames. You may specify more than one user by separating +the usernames with commas (","). If they're logged in they will receive the +log messages. + +Everyone logged on +------------------ + +Emergency messages often go to all users currently online to notify them that +something strange is happening with the system. To specify this wall(1)-feature +use an asterisk ("*"). + +EXAMPLES +======== + +Here are some examples, partially taken from a real existing site and +configuration. Hopefully they answer all questions about configuring this +:manpage:`syslogd(8)`. If not, don't hesitate to contact the mailing list. + +:: + + # Store critical stuff in critical + # + *.=crit;kern.none /var/adm/critical + +This will store all messages of priority crit in the file +``/var/adm/critical``, with the exception of any kernel messages. + +:: + + # Kernel messages are stored in the kernel file, + # critical messages and higher ones also go + # to another host and to the console + # + kern.* /var/adm/kernel + kern.crit @finlandia + kern.crit /dev/console + kern.info;kern.!err /var/adm/kernel-info + +The first rule directs any message that has the kernel facility to the file +``/var/adm/kernel``. (But recall that only the kernel itself can log to this +facility.) + +The second statement directs all kernel messages of priority crit and higher +to the remote host finlandia. This is useful, because if the host crashes +and the disks get irreparable errors you might not be able to read the stored +messages. If they're on a remote host, too, you still can try to find out the +reason for the crash. + +The third rule directs kernel messages of priority crit and higher to the +actual console, so the person who works on the machine will get them, too. + +The fourth line tells the syslogd to save all kernel messages that come with +priorities from info up to warning in the file ``/var/adm/kernel-info``. + +This is an example of the 2nd selector overwriting part of the first one. +The first selector selects kernel messages of priority info and higher. The +second selector filters out kernel messages of priority error and higher. +This leaves just priorities info, notice and warning to get logged. + +:: + + # The tcp wrapper logs with mail.info, we display + # all the connections on tty12 + # + mail.=info /dev/tty12 + +This directs all messages that use ``mail.info`` +(in source ``LOG_MAIL | LOG_INFO``) to ``/dev/tty12``, the 12th console. +For example the tcpwrapper :manpage:`tcpd(8)` uses this as its default. + +:: + + # Write all mail related logs to a file + # + mail.*;mail.!=info /var/adm/mail + +This pattern matches all messages that come with the mail facility, +except for the info priority. These will be stored in the file +``/var/adm/mail``. + +:: + + # Log all mail.info and news.info messages to info + # + mail,news.=info /var/adm/info + +This will extract all messages that come either with mail.info or with +news.info and store them in the file ``/var/adm/info``. + +:: + + # Log info and notice messages to messages file + # + *.=info;*.=notice;\ + mail.none /var/log/messages + +This lets the syslogd log all messages that come with either the info or the +notice priority into the file ``/var/log/messages``, except for all messages +that use the mail facility. + +:: + + # Log info messages to messages file + # + *.=info;\ + mail,news.none /var/log/messages + +This statement causes the syslogd to log all messages that come with the info +priority to the file ``/var/log/messages``. But any message coming either with +the mail or the news facility will not be stored. + +:: + + # Emergency messages will be displayed using wall + # + *.=emerg * + +This rule tells the syslogd to write all emergency messages to all currently +logged in users. This is the wall action. + +:: + + # Messages of the priority alert will be directed + # to the operator + # + *.alert root,joey + +This rule directs all messages of priority alert or higher to the terminals +of the operator, i.e. of the users "root" and "joey" if they're logged in. + +:: + + *.* @finlandia + +This rule would redirect all messages to a remote host called finlandia. +This is useful especially in a cluster of machines where all syslog messages +will be stored on only one machine. + +CONFIGURATION FILE SYNTAX DIFFERENCES +===================================== + +Syslogd uses a slightly different syntax for its configuration file than the +original BSD sources. Originally all messages of a specific priority and above +were forwarded to the log file. The modifiers "=", "!" and "-" were added to +make the syslogd more flexible and to use it in a more intuitive manner. + +The original BSD syslogd doesn't understand spaces as separators between the +selector and the action field. + +BUGS +==== + +The effects of multiple selectors are sometimes not intuitive. For example +"mail.crit,\*.err" will select "mail" facility messages at the level of +"err" or higher, not at the level of "crit" or higher. + +Also, if you specify a selector with an exclamation mark in it which is not +preceded by a corresponding selector without an exclamation mark, nothing +will be logged. Intuitively, the selector "ftp.!alert" on its own will select +all ftp messages with priorities less than alert. In fact it selects nothing. +Similarly "ftp.!=alert" might reasonably be expected to select all ftp messages +other than those with priority alert, but again it selects nothing. It seems +the selectors with exclamation marks in them should only be used as "filters" +following selectors without exclamation marks. + +Finally, using a backslash to divide a line into two doesn't work if the +backslash is used immediately after the end of the selector, without +intermediate whitespace. diff --git a/source/configuration/templates.rst b/source/configuration/templates.rst new file mode 100644 index 0000000..e602241 --- /dev/null +++ b/source/configuration/templates.rst @@ -0,0 +1,908 @@ +********* +Templates +********* + +Description +=========== + +Templates are a key feature of rsyslog. They allow to specify any format +a user might want. They are also used for dynamic file name generation. +Every output in rsyslog uses templates - this holds true for files, user +messages and so on. The database writer expects its template to be a +proper SQL statement - so this is highly customizable too. You might ask +how does all of this work when no templates at all are specified. Good +question ;). The answer is simple, though. Templates compatible with the +stock syslogd formats are hardcoded into rsyslogd. So if no template is +specified, we use one of those hardcoded templates. Search for +"template\_" in rsconf.c and you will find the hardcoded ones. + +Templates are specified by template() objects. They can also be +specified via $template legacy statements. + +.. note:: + + Note: key elements of templates are rsyslog properties. See the + :doc:`rsyslog properties reference <properties>` for a list of which + are available. + + +Template processing +=================== + +Due to lack of standardization regarding logs formats, when a template is +specified it's supposed to include HEADER, as defined in `RFC5424 <https://tools.ietf.org/html/rfc5424>`_ + +It's very important to have this in mind, and also to understand how +`rsyslog parsing <http://www.rsyslog.com/doc/syslog_parsing.html>`_ works. + +For example, if the MSG field is set to "this:is a message" and neither HOSTNAME +nor TAG are specified, the outgoing parser will split the message as: + +.. code-block:: none + + TAG:this: + MSG:is a message + + +The template() object +===================== + +The template() object is used to define templates. Note that it is a +**static** object, that means all templates are defined when rsyslog +reads the config file. As such, templates are not affected by +if-statements or config nesting. + +The basic structure of the template object is as follows: + +.. code-block:: none + + template(parameters) + +In addition to this simpler syntax, list templates (to be described +below) support an extended syntax: + +.. code-block:: none + + template(parameters) { list-descriptions } + +Each template has a parameter **name**, which specifies the template +name, and a parameter **type**, which specifies the template type. The +name parameter must be unique, and behaviour is unpredictable if it is +not. The **type** parameter specifies different template types. +Different types simply enable different ways to specify the template +content. The template type **does not** affect what an (output) plugin +can do with it. So use the type that best fits your needs (from a config +writing point of view!). The following types are available: + +- list +- subtree +- string +- plugin + +The various types are described below. + +List +---- + +In this case, the template is generated by a list of constant and +variable statements. These follow the template spec in curly braces. +This type is also primarily meant to be used with structure-aware outputs, +like ommongodb. However, it also works perfectly with text-based +outputs. We recommend to use this mode if more complex property +substitutions need to be done. In that case, the list-based template +syntax is much clearer than the simple string-based one. + +The list template contains the template header (with **type="list"**) +and is followed by **constant** and **property** statements, given in +curly braces to signify the template statement they belong to. As the +name says, **constant** statements describe constant text and +**property** describes property access. There are many options to +**property**, described further below. Most of these options are used to +extract only partial property contents or to modify the text obtained +(for instance to change its case to upper or lower case). + +To grasp the idea, an actual sample is: + +.. code-block:: none + + template(name="tpl1" type="list") { + constant(value="Syslog MSG is: '") + property(name="msg") + constant(value="', ") + property(name="timereported" dateFormat="rfc3339" caseConversion="lower") + constant(value="\n") + } + +This sample is probably primarily targeted at the usual file-based +output. + +Constant statement +^^^^^^^^^^^^^^^^^^ + +This provides a way to specify constant text. The text is used +literally. It is primarily intended for text-based output, so that some +constant text can be included. For example, if a complex template is +built for file output, one usually needs to finish it by a newline, +which can be introduced by a constant statement. Here is an actual +sample of that use case from the rsyslog testbench: + +:: + + template(name="outfmt" type="list") { + property(name="$!usr!msgnum") + constant(value="\n") + } + +The following escape sequences are recognized inside the constant text: + +- \\\\ - single backslash +- \\n - LF +- \\ooo - (three octal digits) - represents a character with this + octal numerical value (e.g. \\101 equals "A"). Note that three octal digits + must be given (in contrast to some languages, where between one and + three are valid). While we support octal notation, we recommend to + use hex notation as this is better known. +- \\xhh - (where h is a hex digit) - represents a character with this + hexadecimal numerical value (e.g. \\x41 equals "A"). Note that two hexadecimal + digits must be given (in contrast to some languages where either one or two + are valid). +- ... some others ... list needs to be extended + +Note: if an unsupported character follows a backslash, this is treated +as an error. Behaviour is unpredictable in this case. + +To aid usage of the same template both for text-based outputs and +structured ones, constant text without an "outname" parameter will be +ignored when creating the name/value tree for structured outputs. So if +you want to supply some constant text e.g. to mongodb, you must include +an outname, as can be seen here: + +.. code-block:: none + + template(name="outfmt" type="list") { + property(name="$!usr!msgnum") + constant(value="\n" outname="IWantThisInMyDB") + } + +To generate a constant json field, the `format` parameter can be used, as +in this example + +.. code-block:: none + + template(name="outfmt" type="list" option.jsonf="on") { + property(outname="message" name="msg" format="jsonf") + constant(outname="@version" value="1" format="jsonf") + } + +The constant statement in this case will generate `"@version":"1"`. Note that to do +this, both the `value` and the `format` parameters must be given. + +The "constant" statement supports the following parameters: + +- value - the constant value to use +- outname - the output field name (for structured outputs) +- format - can be either empty or `jsonf` + + +Property statement +^^^^^^^^^^^^^^^^^^ + +This statement is used to include property values. It can access all +properties. Also, options permit to specify picking only part of a +property or modifying it. It supports the following parameters: + +- **name** - the name of the property to access + +- **outname** - the output field name (for structured outputs) + +- **dateformat** - the date format to use (only for date-related properties). + `Here <property_replacer.html#property-options>`_ you can find a list of all + property options. **TODO:** right now, the property replacer documentation + contains property format options for string templates, only. The formats for + non-string templates differ. For example, date format options in string + templates start with "date-" whereas those in property statements do not + (e.g. "date-year" vs. just "year"). The technical reason behind this is + that inside string templates, the option must include what it applies + to whereas with the explicit format that is part of the parameter name. + + To create a customised format you can use multiple property options + together. The following example would result in **YYYY-MM-DD**: + +.. code-block:: none + + property(name="timereported" dateformat="year") + constant(value="-") + property(name="timereported" dateformat="month") + constant(value="-") + property(name="timereported" dateformat="day") + +- **date.inUTC** - date shall be shown in UTC (please note that this + requires a bit more performance due to the necessary conversions) + Available since 8.18.0. + +- **caseconversion** - permits to convert case of the text. Supported + values are "lower" and "upper" + +- **controlcharacters** - specifies how to handle control characters. + Supported values are "escape", which escapes them, "space", which + replaces them by a single space, and "drop", which simply removes + them from the string. + +- **securepath** - used for creating pathnames suitable for use in dynafile + templates. Supported values are "drop" and "replace". + +- **format** - specify format on a field basis. Supported values are: + + - "`csv <property_replacer.html#csv>`_\ " for use when csv-data is + generated + - "`json <property_replacer.html#json>`_\ " which formats proper + json content (but without a field header) + - "`jsonf <property_replacer.html#jsonf>`_\ " which formats as a + complete json field + - "`jsonr <property_replacer.html#jsonr>`_\ " which avoids double + escaping the value but makes it safe for a json field + - "`jsonfr <property_replacer.html#jsonfr>`_\ " which is the + combination of "jsonf" and "jsonr". + +- **position.from** - obtain substring starting from this position (1 is + the first position) + +- **position.to** - obtain substring up to this position. As a special + extension available since 8.2302.0. the `position.to` value may be + negative (-n). In this case, all characters from `position.from` to the + end of the actual property string except the last n characters are extracted. + This makes it easy to strip the beginning and end of a string with changing + legth. Let us assume you have a string `"[abc]"` and want to remove the + braces. In this case, use `position.from="2" position.to="-1"` in the + `property()` object. This will result in the string `"abc"` after template + processing. This is especially useful if you want to drop the braces around + the `STRUCTURED-DATA` message property. + +- **position.relativeToEnd** - the from and to position is relative to the + end of the string instead of the usual start of string. (available + since rsyslog v7.3.10) + +- **fixedwidth** - changes behaviour of position.to so that it pads the + source string with spaces up to the value of position.to if the source + string is shorter. "on" or "off" (default) (available since rsyslog + v8.13.0) + +- **compressspace** - compresses multiple spaces (US-ASCII SP character) + inside the string to a single one. This compression happens at a very + late stage in processing. Most importantly, it happens after substring + extraction, so the **position.from** and **position.to** positions + are **NOT** affected by this option. (available since v8.18.0). + +- **field.number** - obtain this field match + +- **field.delimiter** - decimal value of delimiter character for field + extraction + +- **regex.expression** - expression to use + +- **regex.type** - either ERE or BRE + +- **regex.nomatchmode** - what to do if we have no match + +- **regex.match** - match to use + +- **regex.submatch** - submatch to use + +- **droplastlf** - drop a trailing LF, if it is present + +- **mandatory** - signifies a field as mandatory. If set to "on", this + field will always be present in data passed to structured outputs, + even if it is empty. If "off" (the default) empty fields will not be + passed to structured outputs. This is especially useful for outputs + that support dynamic schemas (like ommongodb). + +- **spifno1stsp** - expert options for RFC3164 template processing + +- **datatype** - for "jsonf" format ONLY; permits to set a datatype + Log messages as string data types natively. Thus every property inside + rsyslog is string based. However, in some end systems you need different + data types like numbers of boolean. This setting, in jsonf mode, permits + to configure a desired data type. Supported data types are: + + - number - value is treated as a JSON number and not enclosed in quotes. + If the property is empty, the value 0 is generated. + - string - value is a string and enclosed in quotes + - auto - value is treated as number if numeric and as string otherwise. + The current implementation treats only integers as numeric to avoid + confusion. + - bool - the value is treated as boolean. If it is empty or 0, it will + generate "false", else "true". + + If not specified, 'string' datatype is assumed. + This is a feature of rsyslog 8.1905.0 or later. + +- **onEmpty** - for "jsonf" format ONLY; specifies how empty values + shall be handled. Possible values are: + + - keep - emit the empty element + - skip - completely ignore the element, do not emit anything + - null - emit a JSON 'null' value + + If not specified, 'keep' is assumed. + This is a feature of rsyslog 8.1905.0 or later. + + +Subtree +------- + +Available since rsyslog 7.1.4 + +In this case, the template is generated based on a complete (CEE) +subtree. This type of template is most useful for outputs that know how +to process hierarchical structure, like ommongodb. With that type, the +parameter **subtree** must be specified, which tells which subtree to +use. For example template(name="tpl1" type="subtree" subtree="$!") +includes all CEE data, while template(name="tpl2" type="subtree" +subtree="$!usr!tpl2") includes only the subtree starting at $!usr!tpl2. +The core idea when using this type of template is that the actual data +is prefabricated via set and unset script statements, and the resulting +structure is then used inside the template. This method MUST be used if +a complete subtree needs to be placed *directly* into the object's root. +With all other template types, only subcontainers can be generated. Note +that subtree type can also be used with text-based outputs, like omfile. +HOWEVER, you do not have any capability to specify constant text, and as +such cannot include line breaks. As a consequence, using this template +type for text outputs is usually only useful for debugging or very +special cases (e.g. where the text is interpreted by a JSON parser later +on). + + +Use case +^^^^^^^^ + +A typical use case is to first create a custom subtree and then include +it into the template, like in this small example: + +.. code-block:: none + + set $!usr!tpl2!msg = $msg; + set $!usr!tpl2!dataflow = field($msg, 58, 2); + template(name="tpl2" type="subtree" subtree="$!usr!tpl2") + + +Here, we assume that $msg contains various fields, and the data from a +field is to be extracted and stored - together with the message - as +field content. + + +String +------ + +This closely resembles the legacy template statement. It has a mandatory +parameter **string**, which holds the template string to be applied. A +template string is a mix of constant text and replacement variables (see +property replacer). These variables are taken from message or other +dynamic content when the final string to be passed to a plugin is +generated. String-based templates are a great way to specify textual +content, especially if no complex manipulation to properties is +necessary. + +This is a sample for a string-based template: + +.. code-block:: none + + template(name="tpl3" type="string" + string="%TIMESTAMP:::date-rfc3339% %HOSTNAME% %syslogtag%%msg:::sp-if-no-1st-sp%%msg:::drop-last-lf%\n" + ) + + +The text between percent signs ('%') is interpreted by the rsyslog +:doc:`property replacer <property_replacer>`. In a nutshell, +it contains the property to use as well as options for formatting +and further processing. This is very similar to what the ``property`` +object in list templates does (it actually is just a different language to +express most of the same things). + +Everything outside of the percent signs is constant text. In the +above case, we have mostly spaces between the property values. At the +end of the string, an escape sequence is used. + +Escape sequences permit to specify nonprintable characters. They work +very similar to escape sequences in C and many other languages. They +are initiated by the backslash characters and followed by one or more +characters that specify the actual character. For example \\7 is the +US-ASCII BEL character and \\n is a newline. The set is similar to +what C and perl support, but a bit more limited. + + +Plugin +------ + +In this case, the template is generated by a plugin (which is then +called a "strgen" or "string generator"). The format is fixed as it is +coded. While this is inflexible, it provides superior performance, and +is often used for that reason (not that "regular" templates are slow - +but in very demanding environments that "last bit" can make a +difference). Refer to the plugin's documentation for further details. +For this type, the parameter **plugin** must be specified and must +contain the name of the plugin as it identifies itself. Note that the +plugin must be loaded prior to being used inside a template. +Config example: + + ``template(name="tpl4" type="plugin" plugin="mystrgen")`` + + +Options +^^^^^^^ + +The <options> part is optional. It carries options influencing the +template as a whole and is a part of the template parameters. See details +below. Be sure NOT to mistake template options with property options - +the latter ones are processed by the property replacer and apply to a +SINGLE property, only (and not the whole template). +Template options are case-insensitive. Currently defined are: + +**option.sql** - format the string suitable for a SQL statement in MySQL +format. This will replace single quotes ("'") and the backslash +character by their backslash-escaped counterpart ("\\'" and "\\\\") +inside each field. Please note that in MySQL configuration, the +``NO_BACKSLASH_ESCAPES`` mode must be turned off for this format to work +(this is the default). + +**option.stdsql** - format the string suitable for a SQL statement that +is to be sent to a standards-compliant sql server. This will replace +single quotes ("'") by two single quotes ("''") inside each field. You +must use stdsql together with MySQL if in MySQL configuration the +``NO_BACKSLASH_ESCAPES`` is turned on. + +**option.json** - format the string suitable for a json statement. This +will replace single quotes ("'") by two single quotes ("''") inside each +field. + +**option.jsonf** - format the string as JSON object. This means a leading +and trailing curly brace "{" will be added as well as a comma between all +non-terminal properties and constants. + +**option.casesensitive** - treat property name references as case +sensitive. The default is "off", where all property name references are +first converted to lowercase during template definition. With this +option turned "on", property names are looked up as defined in the +template. Use this option if you have JSON (``$!*``), local (``!.*``), +or global (``$!\\*``) properties which contain uppercase letters. The +normal Rsyslog properties are case-insensitive, so this option is not +needed for properly referencing those properties. + +Use of the options **option.sql**, **option.stdsql**, and +**option.json** are mutually exclusive. Using more than one at the same +time can cause unpredictable behaviour. + +Either the **sql** or **stdsql** option **must** be specified when a +template is used for writing to a database, otherwise injection might +occur. Please note that due to the unfortunate fact that several vendors +have violated the sql standard and introduced their own escape methods, +it is impossible to have a single option doing all the work. So you +yourself must make sure you are using the right format. **If you choose +the wrong one, you are still vulnerable to sql injection.** +Please note that the database writer *checks* that the sql option is +present in the template. If it is not present, the write database action +is disabled. This is to guard you against accidentally forgetting it and +then becoming vulnerable to SQL injection. The sql option can also be +useful with files - especially if you want to import them into a +database on another machine for performance reasons. However, do NOT use +it if you do not have a real need for it - among others, it takes some +toll on the processing time. Not much, but on a really busy system you +might notice it. + +The default template for the write to database action has the sql option +set. As we currently support only MySQL and the sql option matches the +default MySQL configuration, this is a good choice. However, if you have +turned on ``NO_BACKSLASH_ESCAPES`` in your MySQL config, you need to +supply a template with the stdsql option. Otherwise you will become +vulnerable to SQL injection. + +.. code-block:: none + + template (name="TraditionalFormat" type="string" + string="%timegenerated% %HOSTNAME% %syslogtag%%msg%\\n") + + +Examples +======== + +Standard Template for Writing to Files +-------------------------------------- + +.. code-block:: none + + template(name="FileFormat" type="list") { + property(name="timestamp" dateFormat="rfc3339") + constant(value=" ") + property(name="hostname") + constant(value=" ") + property(name="syslogtag") + property(name="msg" spifno1stsp="on" ) + property(name="msg" droplastlf="on" ) + constant(value="\n") + } + +The equivalent string template looks like this: + +.. code-block:: none + + template(name="FileFormat" type="string" + string= "%TIMESTAMP% %HOSTNAME% %syslogtag%%msg:::sp-if-no-1st-sp%%msg:::drop-last-lf%\n" + ) + + +.. note:: + + The template string itself must be on a single line. + + +Standard Template for Forwarding to a Remote Host (RFC3164 mode) +---------------------------------------------------------------- + +.. code-block:: none + + template(name="ForwardFormat" type="list") { + constant(value="<") + property(name="pri") + constant(value=">") + property(name="timestamp" dateFormat="rfc3339") + constant(value=" ") + property(name="hostname") + constant(value=" ") + property(name="syslogtag" position.from="1" position.to="32") + property(name="msg" spifno1stsp="on" ) + property(name="msg") + } + +The equivalent string template looks like this: + +.. code-block:: none + + template(name="forwardFormat" type="string" + string="<%PRI%>%TIMESTAMP:::date-rfc3339% %HOSTNAME% %syslogtag:1:32%%msg:::sp-if-no-1st-sp%%msg%" + ) + +.. note:: + + The template string itself must be on a single line. + + +Standard Template for writing to the MySQL database +--------------------------------------------------- + +.. code-block:: none + + template(name="StdSQLformat" type="list" option.sql="on") { + constant(value="insert into SystemEvents (Message, Facility, FromHost, Priority, DeviceReportedTime, ReceivedAt, InfoUnitID, SysLogTag)") + constant(value=" values ('") + property(name="msg") + constant(value="', ") + property(name="syslogfacility") + constant(value=", '") + property(name="hostname") + constant(value="', ") + property(name="syslogpriority") + constant(value=", '") + property(name="timereported" dateFormat="mysql") + constant(value="', '") + property(name="timegenerated" dateFormat="mysql") + constant(value="', ") + property(name="iut") + constant(value=", '") + property(name="syslogtag") + constant(value="')") + } + +The equivalent string template looks like this: + +.. code-block:: none + + template(name="stdSQLformat" type="string" option.sql="on" + string="insert into SystemEvents (Message, Facility, FromHost, Priority, DeviceReportedTime, ReceivedAt, InfoUnitID, SysLogTag) values ('%msg%', %syslogfacility%, '%HOSTNAME%', %syslogpriority%, '%timereported:::date-mysql%', '%timegenerated:::date-mysql%', %iut%, '%syslogtag%')" + ) + +.. note:: + + The template string itself must be on a single line. + + +Generating JSON +--------------- + +This is especially useful for RESTful APIs, like for example ElasticSearch provides. + +This template + +.. code-block:: none + + template(name="outfmt" type="list" option.jsonf="on") { + property(outname="@timestamp" name="timereported" dateFormat="rfc3339" format="jsonf") + property(outname="host" name="hostname" format="jsonf") + property(outname="severity" name="syslogseverity" caseConversion="upper" format="jsonf" datatype="number") + property(outname="facility" name="syslogfacility" format="jsonf" datatype="number") + property(outname="syslog-tag" name="syslogtag" format="jsonf") + property(outname="source" name="app-name" format="jsonf" onEmpty="null") + property(outname="message" name="msg" format="jsonf") + + } + +Generates output similar to this + +.. code-block:: none + + {"@timestamp":"2018-03-01T01:00:00+00:00", "host":"172.20.245.8", "severity":7, "facility":20, "syslog-tag":"tag", "source":"tag", "message":" msgnum:00000000:"} + +Pretty-printed this looks like + +.. code-block:: none + + { + "@timestamp": "2018-03-01T01:00:00+00:00", + "host": "172.20.245.8", + "severity": 7, + "facility": 20, + "syslog-tag": "tag", + "source": "tag", + "message": " msgnum:00000000:" + } + + +.. note:: + + The output is **not** pretty-printed as this is just waste of resources when + used in RESTful APIs. + +If the "app-name" property is empty, a JSON null value is generated as the `onEmpty="null"` +parameter is used + +.. code-block:: none + + {"@timestamp":"2018-03-01T01:00:00+00:00", "host":"172.20.245.8", "severity":7, "facility":20, "syslog-tag":"tag", "source":null, "message":" msgnum:00000000:"} + + +Creating Dynamic File Names for omfile +-------------------------------------- + +Templates can be used to generate actions with dynamic file names. +For example, if you would like to split syslog messages from different hosts +to different files (one per host), you can define the following template: + +.. code-block:: none + + template (name="DynFile" type="string" string="/var/log/system-%HOSTNAME%.log") + + +Reserved Template Names +----------------------- + +Template names beginning with "RSYSLOG\_" are reserved for rsyslog use. +Do NOT use them, otherwise you may cause conflicts in the future +(and quite unpredictable behaviour). There is a small set of pre-defined +templates that you can use without the need to define them: + +**RSYSLOG_TraditionalFileFormat** - The "old style" default log file +format with low-precision timestamps. + +.. code-block:: none + + template(name="RSYSLOG_TraditionalFileFormat" type="string" + string="%TIMESTAMP% %HOSTNAME% %syslogtag%%msg:::sp-if-no-1st-sp%%msg:::drop-last-lf%\n") + +**RSYSLOG_FileFormat** - A modern-style logfile format similar to +TraditionalFileFormat, both with high-precision timestamps and +timezone information. + +.. code-block:: none + + template(name="RSYSLOG_FileFormat" type="list") { + property(name="timereported" dateFormat="rfc3339") + constant(value=" ") + property(name="hostname") + constant(value=" ") + property(name="syslogtag") + property(name="msg" spifno1stsp="on") + property(name="msg" droplastlf="on") + constant(value="\n") + } + +**RSYSLOG_TraditionalForwardFormat** - The traditional forwarding format +with low-precision timestamps. Most useful if you send messages to +other syslogd's or rsyslogd below version 3.12.5. + +.. code-block:: none + + template(name="RSYSLOG_TraditionalForwardFormat" type="string" + string="<%PRI%>%TIMESTAMP% %HOSTNAME% %syslogtag:1:32%%msg:::sp-if-no-1st-sp%%msg%") + +**RSYSLOG_SysklogdFileFormat** - Sysklogd compatible log file format. If +used with options: ``$SpaceLFOnReceive on``, +``$EscapeControlCharactersOnReceive off``, ``$DropTrailingLFOnReception off``, +the log format will conform to sysklogd log format. + +.. code-block:: none + + template(name="RSYSLOG_SysklogdFileFormat" type="string" + string="%TIMESTAMP% %HOSTNAME% %syslogtag%%msg:::sp-if-no-1st-sp%%msg%\n") + +**RSYSLOG_ForwardFormat** - a new high-precision forwarding format very +similar to the traditional one, but with high-precision timestamps +and timezone information. Recommended to be used when sending +messages to rsyslog 3.12.5 or above. + +.. code-block:: none + + template(name="RSYSLOG_ForwardFormat" type="string" + string="<%PRI%>%TIMESTAMP:::date-rfc3339% %HOSTNAME% %syslogtag:1:32%%msg:::sp-if-no-1st-sp%%msg%") + +**RSYSLOG_SyslogProtocol23Format** - the format specified in IETF's +internet-draft ietf-syslog-protocol-23, which is very close to the actual +syslog standard `RFC5424 <https://tools.ietf.org/html/rfc5424>`_ (we couldn't +update this template as things were in production for quite some time when +RFC5424 was finally approved). This format includes several improvements. +You may use this format with all relatively recent versions of rsyslog or syslogd. + +.. code-block:: none + + template(name="RSYSLOG_SyslogProtocol23Format" type="string" + string="<%PRI%>1 %TIMESTAMP:::date-rfc3339% %HOSTNAME% %APP-NAME% %PROCID% %MSGID% %STRUCTURED-DATA% %msg%\n") + +**RSYSLOG_DebugFormat** - a special format used for troubleshooting +property problems. This format is meant to be written to a log file. +Do **not** use for production or remote forwarding. + +.. code-block:: none + + template(name="RSYSLOG_DebugFormat" type="list") { + constant(value="Debug line with all properties:\nFROMHOST: '") + property(name="fromhost") + constant(value="', fromhost-ip: '") + property(name="fromhost-ip") + constant(value="', HOSTNAME: '") + property(name="hostname") + constant(value="', PRI: '") + property(name="pri") + constant(value=",\nsyslogtag '") + property(name="syslogtag") + constant(value="', programname: '") + property(name="programname") + constant(value="', APP-NAME: '") + property(name="app-name") + constant(value="', PROCID: '") + property(name="procid") + constant(value="', MSGID: '") + property(name="msgid") + constant(value="',\nTIMESTAMP: '") + property(name="timereported") + constant(value="', STRUCTURED-DATA: '") + property(name="structured-data") + constant(value="',\nmsg: '") + property(name="msg") + constant(value="'\nescaped msg: '") + property(name="msg" controlcharacters="drop") + constant(value="'\ninputname: ") + property(name="inputname") + constant(value=" rawmsg: '") + property(name="rawmsg") + constant(value="'\n$!:") + property(name="$!") + constant(value="\n$.:") + property(name="$.") + constant(value="\n$/:") + property(name="$/") + constant(value="\n\n") + } + +**RSYSLOG_WallFmt** - Contains information about the host and the time the +message was generated and at the end the syslogtag and message itself. + +.. code-block:: none + + template(name="RSYSLOG_WallFmt" type="string" + string="\r\n\7Message from syslogd@%HOSTNAME% at %timegenerated% ...\r\n%syslogtag%%msg%\n\r") + +**RSYSLOG_StdUsrMsgFmt** - The syslogtag followed by the message is returned. + +.. code-block:: none + + template(name="RSYSLOG_StdUsrMsgFmt" type="string" + string=" %syslogtag%%msg%\n\r") + +**RSYSLOG_StdDBFmt** - Generates a insert command with the message +properties, into table SystemEvents for a mysql database. + +.. code-block:: none + + template(name="RSYSLOG_StdDBFmt" type="list") { + constant(value="insert into SystemEvents (Message, Facility, FromHost, Priority, DeviceReportedTime, ReceivedAt, InfoUnitID, SysLogTag)") + constant(value=" values ('") + property(name="msg") + constant(value="', ") + property(name="syslogfacility") + constant(value=", '") + property(name="hostname") + constant(value="', ") + property(name="syslogpriority") + constant(value=", '") + property(name="timereported" dateFormat="date-mysql") + constant(value="', '") + property(name="timegenerated" dateFormat="date-mysql") + constant(value="', ") + property(name="iut") + constant(value=", '") + property(name="syslogtag") + constant(value="')") + } + +**RSYSLOG_StdPgSQLFmt** - Generates a insert command with the message +properties, into table SystemEvents for a pgsql database. + +.. code-block:: none + + template(name="RSYSLOG_StdPgSQLFmt" type="string" + string="insert into SystemEvents (Message, Facility, FromHost, Priority, DeviceReportedTime, + ReceivedAt, InfoUnitID, SysLogTag) values ('%msg%', %syslogfacility%, '%HOSTNAME%', + %syslogpriority%, '%timereported:::date-pgsql%', '%timegenerated:::date-pgsql%', %iut%, + '%syslogtag%')") + +**RSYSLOG_spoofadr** - Generates a message containing nothing more than +the ip address of the sender. + +.. code-block:: none + + template(name="RSYSLOG_spoofadr" type="string" string="%fromhost-ip%") + +**RSYSLOG_StdJSONFmt** - Generates a JSON structure containing the message +properties. + +.. code-block:: none + + template(name="RSYSLOG_StdJSONFmt" type="string" + string="{\"message\":\"%msg:::json%\",\"fromhost\":\"%HOSTNAME:::json%\",\"facility\": + \"%syslogfacility-text%\",\"priority\":\"%syslogpriority-text%\",\"timereported\": + \"%timereported:::date-rfc3339%\",\"timegenerated\": + \"%timegenerated:::date-rfc3339%\"}") + + + +The LEGACY \$template statement +=============================== + +Legacy format provides limited functionality, but is still frequently used. +So you probably need to at least be able to understand them. Legacy format +is also good for fairly simple templates. + +In legacy, only string templates are supported. The full format is as follows: + +.. code-block:: none + + $template myname,<string-template> + +Here, *myname* is the name of the template (like the *name="myname"* property in +modern template format). The *<string-template>* is exactly the *string* property +like in modern template format. + +Take for example the following modern template object: + +.. code-block:: none + + template(name="tpl3" type="string" + string="%TIMESTAMP:::date-rfc3339% %HOSTNAME% %syslogtag%%msg:::sp-if-no-1st-sp%%msg:::drop-last-lf%\n" + ) + + +It translates to the following legacy template statement: + +.. code-block:: none + + $template tpl3,"%TIMESTAMP:::date-rfc3339% %HOSTNAME% %syslogtag%%msg:::sp-if-no-1st-sp%%msg:::drop-last-lf%\n" + + + +See Also +-------- + +- `How to bind a + template <http://www.rsyslog.com/how-to-bind-a-template/>`_ +- `Adding the BOM to a + message <http://www.rsyslog.com/adding-the-bom-to-a-message/>`_ +- `How to separate log files by host name of the sending + device <http://www.rsyslog.com/article60/>`_ + diff --git a/source/configuration/timezone.rst b/source/configuration/timezone.rst new file mode 100644 index 0000000..c297d06 --- /dev/null +++ b/source/configuration/timezone.rst @@ -0,0 +1,68 @@ +timezone +======== + +.. index:: ! timezone +.. _cfgobj_input: + +The ``timezone`` object, as its name suggests, describes timezones. +Currently, they are used by message parser modules to interpret +timestamps that contain timezone information via a timezone string +(but not an offset, e.g. "CET" but not "-01:00"). The object describes +an UTC offset for a given timezone ID. + +Each timestamp object adds the zone definition to a global table +with timezone information. Duplicate IDs are forbidden, but the +same offset may be used with multiple IDs. + +As with other configuration objects, parameters for this +object are case-insensitive. + + +Parameters +---------- + +.. function:: id <name-string> + + *Mandatory* + + This identifies the timezone. Note that this id must match the zone + name as reported within the timestamps. Different devices and vendors + use different, often non-standard, names and so it is important to use + the actual ids that messages contain. For multiple devices, this may + mean that you may need to include multiple definitions, each one with a + different id, for the same time zone. For example, it is seen that + some devices report "CEST" for central European daylight savings time + while others report "METDST" for it. + +.. function:: offset <[+/-]><hh>:<mm> + + *Mandatory* + + This defines the timezone offset over UTC. It must always be 6 characters + and start with a "+" (east of UTC) or "-" (west uf UTC) followed by a + two-digit hour offset, a colon and a two-digit minute offset. Hour offsets + can be in the range from zero to twelve, minute offsets in the range from + zero to 59. Any other format is invalid. + +Sample +------ +The following sample defines UTC time. From rsyslog PoV, it doesn't +matter if a plus or minus offset prefix is used. For consistency, +plus is suggested. + +:: + + timezone(id="UTC" offset="+00:00") + +The next sample defines some common timezones: + +:: + + timezone(id="CET" offset="+01:00") + timezone(id="CEST" offset="+02:00") + timezone(id="METDST" offset="+02:00") # duplicate to support differnt formats + timezone(id="EST" offset="-05:00") + timezone(id="EDT" offset="-04:00") + timezone(id="PST" offset="-08:00") + timezone(id="PDT" offset="-07:00") + diff --git a/source/containers/container_features.rst b/source/containers/container_features.rst new file mode 100644 index 0000000..7e00db8 --- /dev/null +++ b/source/containers/container_features.rst @@ -0,0 +1,9 @@ +Container-Features +------------------ + +Upon start, rsyslog checks if it is running as pid 1. If so, this is +a clear indication it is running inside a container. This changes +some parameter defaults: + +- :kbd:`Control-C` is enabled +- no pid file is written diff --git a/source/containers/docker_specifics.rst b/source/containers/docker_specifics.rst new file mode 100644 index 0000000..7459df8 --- /dev/null +++ b/source/containers/docker_specifics.rst @@ -0,0 +1,23 @@ +docker specifics +---------------- + +This page talks about docker, as this is the platform the rsyslog +team has hands-on experience with. Some or all of the information +might also apply to other solutions. + +Potential Trouble causes: + +- container terminate timeout + + By default, a docker container has 10 seconds to shut down. If rsyslog + is running with a large queue that needs to be persisted to disk, + that amount of time might be insufficient. This can lead to a hard + kill of rsyslog and potentially cause queue corruption. + +- shared work directories + + Shared work directories call for problems and shall be avoided. If + multiple instances use the same work directory, the may even overwrite + some files, resulting in a total mess. Each container instance should + have its own work directory. + diff --git a/source/containers/index.rst b/source/containers/index.rst new file mode 100644 index 0000000..9699a00 --- /dev/null +++ b/source/containers/index.rst @@ -0,0 +1,20 @@ +rsyslog and containers +====================== + +In this chapter, we describe how rsyslog can be used together with +containers. + +All versions of rsyslog work well in containers. Versions beginning with +8.32.0 have also been made explicitly container-aware and provide some +extra features that are useful inside containers. + +Note: the sources for docker containers created by the rsyslog project +can be found at https://github.com/rsyslog/rsyslog-docker - these may +be useful as a starting point for similar efforts. Feedback, bug +reports and pull requests are also appreciated for this project. + +.. toctree:: + :maxdepth: 2 + + container_features + docker_specifics diff --git a/source/dataflow.png b/source/dataflow.png Binary files differnew file mode 100644 index 0000000..fd614d8 --- /dev/null +++ b/source/dataflow.png diff --git a/source/development/config_data_model.rst b/source/development/config_data_model.rst new file mode 100644 index 0000000..0bff2af --- /dev/null +++ b/source/development/config_data_model.rst @@ -0,0 +1,173 @@ +The rsyslog config data model +============================= + +This document describes the config data model on a high layer. +For details, it is suggested to review the actual source code. +The aim of this document is to provide general understanding for +both rsyslog developers as well as developers writing config +management systems. + +Objects +======= +Most config objects live in a flat space and are global to rsyslog. +However, actual rule processing is done via a script-like language. +These config scripts need to be represented via a tree structure. + +Note that the language as currently implemented is Turing-complete +if the user makes use of very tricky constructs. It was never our +intention to provide a Turing-complete language and we will probably +try to disable these tricks in the future. However, this is not a +priority for us, as these users get what they deserve. For someone +involved with the config, it probably is sufficient to know that +loops are **not** supported by the config language (even though you +can create loop-like structures). Thus, a tree is fully sufficient +to represent any configuration. + +In the following sections, we'll quickly describe variables/properties, +flat structure elements and the execution tree. + +Variables/Properties +-------------------- +Rsyslog supports + +* traditional syslog (RFC-based) message properties +* structured data content, including any non-syslog properties +* Variables + + - global + - local + - message-enhancing (like message properties) + +A description of these properties and variables is available elsewhere. As +far as a config processor is concerned, the important thing to know is +that they be used during template definitions and script operations. + +Flat Elements +------------- + +Global Parameters +^^^^^^^^^^^^^^^^^ +This element must contain all global parameters settable by rsyslog. +This includes elements from the global() as well as main_queue() config +statements. As of this writing, some global parameter can only be set +by legacy statements. + +Note that main_queue() actually is a full queue definition. + +Modules +^^^^^^^ +This contains all loaded modules, among others: + +* input modules +* output modules +* message modification modules +* message parsers + +Note that for historical reasons some output modules are directly linked +into rsyslog and must not be specified. + +Each module must be given only once. The data object must contain all +module-global parameters. + +Inputs +^^^^^^ +Describes all defined inputs with their parameters. Is build from the +input() statement or its legacy equivalent (ugly). Contains links to + +* module used for input +* ruleset used for processing + +Rulesets +^^^^^^^^ +They contain the tree-like execution structure. However, rulesets +itself are flat and cannot be nested. Note that there exists statements +that permit rulesets to call into each other, but all rulesets are in +the same flat top-level space. + +Note that a ruleset has an associated queue object which (by default) +operates in direct mode. As a reminder, direct queues do not queue or +buffer any of the queue elements. In most cases this is sufficient, +but if the ruleset is bound to an input or is used to run +multiple actions independently (e.g., forwarding messages to two +destinations), then you should configure the associated queue object +as a real queue. + +See the :doc:`Understanding rsyslog Queues <../concepts/queues>` or +:doc:`Turning Lanes and Rsyslog Queues <../whitepapers/queues_analogy>` docs +for more information. + +Hierarchical Elements +--------------------- +These are used for rule execution. They are somewhat hard to fit into a +traditional config scheme, as they provide full tree-like branching +structure. + +Basically, a tree consists of statements and evaluations. Consider the +ruleset to be the root of the execution tree. It is rather common that +the tree's main level is a long linked list, with only actions being +branched out. This, for example, happens with a traditional +rsyslog.conf setting, which only contains files to be written based +on some priority filters. However, one must not be tricked into +thinking that this basic case is sufficient to support as enterprise +users typically create far more complex cases. + +In essence, rsyslog walks the tree, and executes statements while it +does so. Usually, a filter needs to be evaluated and execution branches +based on the filter outcome. The tree actually **is** an AST. + +Execution Statements +^^^^^^^^^^^^^^^^^^^^ +These are most easy to implement as they are end nodes (and as such +nothing can be nested under them). They are most importantly created by +the action() config object, but also with statements like "set" +and "unset". Note that "call" is also considered a terminal node, even +though it executes *another* ruleset. + +Note that actions have associated queues, so a queue object and its +parameter need to be present. When building configurations interactively, +it is suggested that the default is either not to configure queue parameters +by default or to do this only for actions where it makes sense (e.g. +connection to remote systems which may go offline). + +Expression Evaluation +^^^^^^^^^^^^^^^^^^^^^ +A full expression evaluation engine is available who does the typical +programming-language type of expression processing. The usual mathematical, +boolean and string operations are supported, as well as functions. As of +this writing, functions are hard-coded into rsyslog but may in the future +be part of a loadable module. Evaluations can access all rsyslog properties +and variables. They may be nested arbitrarily deep. + +Control-of-Flow Statements +^^^^^^^^^^^^^^^^^^^^^^^^^^ +Remember that rsyslog does intentionally not support loop statements. So +control-of-flow boils down to + +* conditional statements + + - "if ... then ... else ..." + - syslog PRI-based filters + - property-based filters + +* stop + +Where "stop" terminates processing of this message. The conditional statements +contain subbranches, where "if" contains both "then" and "else" subbranches +and the other two only the "then" subbranch (Note: inside the execution +engine, the others may also have "else" branches, but these are result +of the rsyslog config optimizer run and cannot configured by the user). + +When executing a config script, rsyslog executes the subbranch in question +and then continues to evaluate the next statement in the currently +executing branch that contained the conditional statement. If there is no +next statement, it goes up one layer. This is continued until the last +statement of the root statement list is reached. At that point execution +of the message is terminated and the message object destructed. +Again, think AST, as this is exactly what it is. + +Note on Queue Objects +--------------------- +Queue objects are **not** named objects inside the rsyslog configuration. +So their data is always contained with the object that uses the queue +(action(), ruleset(), main_queue()). From a UI perspective, this +unfortunately tends to complicate a config builder a bit. diff --git a/source/development/debugging.rst b/source/development/debugging.rst new file mode 100644 index 0000000..9b3a46d --- /dev/null +++ b/source/development/debugging.rst @@ -0,0 +1,45 @@ +Debugging +========= + +**Author:** Pascal Withopf <pascalwithopf1@gmail.com> + +Target audience are developers and users who need to debug an error with tests. +For debugging with rsyslog.conf see :doc:`troubleshooting <../troubleshooting/index>`. + +Debugging with tests +-------------------- + +| When you want to solve a specific problem you will probably create a test +| and want to debug with it instead of configuring rsyslog. If you want to +| write a debug log you need to open the file **../rsyslog/tests/diag.sh** +| and delete the **#** in front of the two lines: + +| **export RSYSLOG_DEBUG="debug nologfuncflow noprintmutexaction nostdout"** +| **export RSYSLOG_DEBUGLOG="log"** + +| A debug log will be written now, but remember to put the **#** back again +| before committing your changes. Otherwise it won't work. + +Memory debugging +---------------- + +| You can't use multiple memory debugger at the same time. This will resort +| in errors. Also remember to undo all changes in diag.sh after you are done, +| because it will also resort in errors if you commit them with your work. + +Valgrind +~~~~~~~~ + +| If you want to use Valgrind you need to enable it for tests. +| To do that open the file **../rsyslog/tests/diag.sh** and delete the **#** +| in front of the line: +| **valgrind="valgrind --malloc-fill=ff --free-fill=fe --log-fd=1"** +| This will enable valgrind and you will have extra debugging in your test-suite.log file. + +Address sanitizer +~~~~~~~~~~~~~~~~~ + +| If you want to use address sanitizer you need to set your CFLAGS. Use this command: +| **export CFLAGS="-g -fsanitizer=address"** +| After this is done you need to configure and build rsyslog again, otherwise it won't work. + diff --git a/source/development/dev_codestyle.rst b/source/development/dev_codestyle.rst new file mode 100644 index 0000000..f5407a2 --- /dev/null +++ b/source/development/dev_codestyle.rst @@ -0,0 +1,15 @@ +rsyslog code style +================== + +**Note**: code style is still under construction. This guide lists +some basic style requirements. + +**Code that does not match the code style guide will not pass CI testing.** + +The following is required right now: + + * we use ANSI C99 + * indentation is done with tabs, not spaces + * trailing whitespace in lines is not permitted + * lines longer than 120 characters are not permitted; + everything over 120 chars is rejected and must be reformatted. diff --git a/source/development/dev_oplugins.rst b/source/development/dev_oplugins.rst new file mode 100644 index 0000000..5fb7baf --- /dev/null +++ b/source/development/dev_oplugins.rst @@ -0,0 +1,371 @@ +Writing Rsyslog Output Plugins +============================== + +This page is the begin of some developer documentation for writing +output plugins. Doing so is quite easy (and that was a design goal), but +there currently is only sparse documentation on the process available. I +was tempted NOT to write this guide here because I know I will most +probably not be able to write a complete guide. + +However, I finally concluded that it may be better to have some +information and pointers than to have nothing. + +Getting Started and Samples +--------------------------- + +The best to get started with rsyslog plugin development is by looking at +existing plugins. All that start with "om" are **o**\ utput +**m**\ odules. That means they are primarily thought of being message +sinks. In theory, however, output plugins may aggregate other +functionality, too. Nobody has taken this route so far so if you would +like to do that, it is highly suggested to post your plan on the rsyslog +mailing list, first (so that we can offer advice). + +The rsyslog distribution tarball contains the omstdout plugin which is +extremely well targeted for getting started. Just note that this plugin +itself is not meant for production use. But it is very simplistic and so +a really good starting point to grasp the core ideas. + +In any case, you should also read the comments in +./runtime/module-template.h. Output plugins are built based on a large +set of code-generating macros. These macros handle most of the plumbing +needed by the interface. As long as no special callback to rsyslog is +needed (it typically is not), an output plugin does not really need to +be aware that it is executed by rsyslog. As a plug-in programmer, you +can (in most cases) "code as usual". However, all macros and entry +points need to be provided and thus reading the code comments in the +files mentioned is highly suggested. + +For testing, you need rsyslog's debugging support. Some useful +information is given in "`troubleshooting rsyslog <troubleshoot.html>`_ +from the doc set. + +Special Topics +-------------- + +Threading +~~~~~~~~~ + +Rsyslog uses massive parallel processing and multithreading. However, a +plugin's entry points are guaranteed to be never called concurrently +**for the same action**. That means your plugin must be able to be +called concurrently by two or more threads, but you can be sure that for +the same instance no concurrent calls happen. This is guaranteed by the +interface specification and the rsyslog core guards against multiple +concurrent calls. An instance, in simple words, is one that shares a +single instanceData structure. + +So as long as you do not mess around with global data, you do not need +to think about multithreading (and can apply a purely sequential +programming methodology). + +Please note that during the configuration parsing stage of execution, +access to global variables for the configuration system is safe. In that +stage, the core will only call sequentially into the plugin. + +Getting Message Data +~~~~~~~~~~~~~~~~~~~~ + +The doAction() entry point of your plugin is provided with messages to +be processed. It will only be activated after filtering and all other +conditions, so you do not need to apply any other conditional but can +simply process the message. + +Note that you do NOT receive the full internal representation of the +message object. There are various (including historical) reasons for +this and, among others, this is a design decision based on security. + +Your plugin will only receive what the end user has configured in a +$template statement. However, starting with 4.1.6, there are two ways of +receiving the template content. The default mode, and in most cases +sufficient and optimal, is to receive a single string with the expanded +template. As I said, this is usually optimal, think about writing things +to files, emailing content or forwarding it. + +The important philosophy is that a plugin should **never** reformat any +of such strings - that would either remove the user's ability to fully +control message formats or it would lead to duplicating code that is +already present in the core. If you need some formatting that is not yet +present in the core, suggest it to the rsyslog project, best done by +sending a patch ;), and we will try hard to get it into the core (so +far, we could accept all such suggestions - no promise, though). + +If a single string seems not suitable for your application, the plugin +can also request access to the template components. The typical use case +seems to be databases, where you would like to access properties via +specific fields. With that mode, you receive a char \*\* array, where +each array element points to one field from the template (from left to +right). Fields start at array index 0 and a NULL pointer means you have +reached the end of the array (the typical Unix "poor man's linked list +in an array" design). Note, however, that each of the individual +components is a string. It is not a date stamp, number or whatever, but +a string. This is because rsyslog processes strings (from a high-level +design look at it) and so this is the natural data type. Feel free to +convert to whatever you need, but keep in mind that malformed packets +may have lead to field contents you'd never expected... + +If you like to use the array-based parameter passing method, think that +it is only available in rsyslog 4.1.6 and above. If you can accept that +your plugin will not be working with previous versions, you do not need +to handle pre 4.1.6 cases. However, it would be "nice" if you shut down +yourself in these cases - otherwise the older rsyslog core engine will +pass you a string where you expect the array of pointers, what most +probably results in a segfault. To check whether or not the core +supports the functionality, you can use this code sequence: + +:: + + + BEGINmodInit() + rsRetVal localRet; + rsRetVal (*pomsrGetSupportedTplOpts)(unsigned long *pOpts); + unsigned long opts; + int bArrayPassingSupported; /* does core support template passing as an array? */ + CODESTARTmodInit + *ipIFVersProvided = CURR_MOD_IF_VERSION; /* we only support the current interface specification */ + CODEmodInit_QueryRegCFSLineHdlr + /* check if the rsyslog core supports parameter passing code */ + bArrayPassingSupported = 0; + localRet = pHostQueryEtryPt((uchar*)"OMSRgetSupportedTplOpts", &pomsrGetSupportedTplOpts); + if(localRet == RS_RET_OK) { + /* found entry point, so let's see if core supports array passing */ + CHKiRet((*pomsrGetSupportedTplOpts)(&opts)); + if(opts & OMSR_TPL_AS_ARRAY) + bArrayPassingSupported = 1; + } else if(localRet != RS_RET_ENTRY_POINT_NOT_FOUND) { + ABORT_FINALIZE(localRet); /* Something else went wrong, what is not acceptable */ + } + DBGPRINTF("omstdout: array-passing is %ssupported by rsyslog core.\n", bArrayPassingSupported ? "" : "not "); + + if(!bArrayPassingSupported) { + DBGPRINTF("rsyslog core too old, shutting down this plug-in\n"); + ABORT_FINALIZE(RS_RET_ERR); + } + +The code first checks if the core supports the OMSRgetSupportedTplOpts() +API (which is also not present in all versions!) and, if so, queries the +core if the OMSR\_TPL\_AS\_ARRAY mode is supported. If either does not +exits, the core is too old for this functionality. The sample snippet +above then shuts down, but a plugin may instead just do things +different. In omstdout, you can see how a plugin may deal with the +situation. + +**In any case, it is recommended that at least a graceful shutdown is +made and the array-passing capability not blindly be used.** In such +cases, we can not guard the plugin from segfaulting and if the plugin +(as currently always) is run within rsyslog's process space, that +results in a segfault for rsyslog. So do not do this. + +Another possible mode is OMSR\_TPL\_AS\_JSON, where instead of the +template a json-c memory object tree is passed to the module. The module +can extract data via json-c API calls. It MUST NOT modify the provided +structure. This mode is primarily aimed at plugins that need to process +tree-like data, as found for example in MongoDB or ElasticSearch. + +Batching of Messages +~~~~~~~~~~~~~~~~~~~~ + +Starting with rsyslog 4.3.x, batching of output messages is supported. +Previously, only a single-message interface was supported. + +With the **single message** plugin interface, each message is passed via +a separate call to the plugin. Most importantly, the rsyslog engine +assumes that each call to the plugin is a complete transaction and as +such assumes that messages be properly committed after the plugin returns +to the engine. + +With the **batching** interface, rsyslog employs something along the +line of "transactions". Obviously, the rsyslog core can not make +non-transactional outputs to be fully transactional. But what it can is +support that the output tells the core which messages have been committed +by the output and which not yet. The core can than take care of those +uncommitted messages when problems occur. For example, if a plugin has +received 50 messages but not yet told the core that it committed them, +and then returns an error state, the core assumes that all these 50 +messages were **not** written to the output. The core then requeues all +50 messages and does the usual retry processing. Once the output plugin +tells the core that it is ready again to accept messages, the rsyslog +core will provide it with these 50 not yet committed messages again +(actually, at this point, the rsyslog core no longer knows that it is +re-submitting the messages). If, in contrary, the plugin had told rsyslog +that 40 of these 50 messages were committed (before it failed), then only +10 would have been requeued and resubmitted. + +In order to provide an efficient implementation, there are some (mild) +constraints in that transactional model: first of all, rsyslog itself +specifies the ultimate transaction boundaries. That is, it tells the +plugin when a transaction begins and when it must finish. The plugin is +free to commit messages in between, but it **must** commit all work done +when the core tells it that the transaction ends. All messages passed in +between a begin and end transaction notification are called a batch of +messages. They are passed in one by one, just as without transaction +support. Note that batch sizes are variable within the range of 1 to a +user configured maximum limit. Most importantly, that means that plugins +may receive batches of single messages, so they are required to commit +each message individually. If the plugin tries to be "smarter" than the +rsyslog engine and does not commit messages in those cases (for +example), the plugin puts message stream integrity at risk: once rsyslog +has notified the plugin of transaction end, it discards all messages as +it considers them committed and save. If now something goes wrong, the +rsyslog core does not try to recover lost messages (and keep in mind +that "goes wrong" includes such uncontrollable things like connection +loss to a database server). So it is highly recommended to fully abide +to the plugin interface details, even though you may think you can do it +better. The second reason for that is that the core engine will have +configuration settings that enable the user to tune commit rate to their +use-case specific needs. And, as a relief: why would rsyslog ever decide +to use batches of one? There is a trivial case and that is when we have +very low activity so that no queue of messages builds up, in which case +it makes sense to commit work as it arrives. (As a side-note, there are +some valid cases where a timeout-based commit feature makes sense. This +is also under evaluation and, once decided, the core will offer an +interface plus a way to preserve message stream integrity for +properly-crafted plugins). + +The second restriction is that if a plugin makes commits in between +(what is perfectly legal) those commits must be in-order. So if a commit +is made for message ten out of 50, this means that messages one to nine +are also committed. It would be possible to remove this restriction, but +we have decided to deliberately introduce it to simplify things. + +Output Plugin Transaction Interface +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +In order to keep compatible with existing output plugins (and because it +introduces no complexity), the transactional plugin interface is build +on the traditional non-transactional one. Well... actually the +traditional interface was transactional since its introduction, in the +sense that each message was processed in its own transaction. + +So the current +``doAction() entry point can be considered to have this structure (from the transactional interface point of view):`` + +:: + + doAction() + { + beginTransaction() + ProcessMessage() + endTransaction() + } + +For the **transactional interface**, we now move these implicit +``beginTransaction()`` and ``endTransaction(()`` call out of the message +processing body, resulting is such a structure: + +:: + + beginTransaction() + { + /* prepare for transaction */ + } + + doAction() + { + ProcessMessage() + /* maybe do partial commits */ + } + + endTransaction() + { + /* commit (rest of) batch */ + } + +And this calling structure actually is the transactional interface! It +is as simple as this. For the new interface, the core calls a +``beginTransaction()`` entry point inside the plugin at the start of the +batch. Similarly, the core call ``endTransaction()`` at the end of the +batch. The plugin must implement these entry points according to its +needs. + +But how does the core know when to use the old or the new calling +interface? This is rather easy: when loading a plugin, the core queries +the plugin for the ``beginTransaction()`` and ``endTransaction()`` entry +points. If the plugin supports these, the new interface is used. If the +plugin does not support them, the old interface is used and rsyslog +implies that a commit is done after each message. Note that there is no +special "downlevel" handling necessary to support this. In the case of +the non-transactional interface, rsyslog considers each completed call +to ``doAction`` as partial commit up to the current message. So +implementation inside the core is very straightforward. + +Actually, **we recommend that the transactional entry points only be +defined by those plugins that actually need them**. All others should +not define them in which case the default commit behaviour inside +rsyslog will apply (thus removing complexity from the plugin). + +In order to support partial commits, special return codes must be +defined for ``doAction``. All those return codes mean that processing +completed successfully. But they convey additional information about the +commit status as follows: + ++----------------------------------+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ +| *RS\_RET\_OK* | The record and all previous inside the batch has been committed. *Note:* this definition is what makes integrating plugins without the transaction being/end calls so easy - this is the traditional "success" return state and if every call returns it, there is no need for actually calling ``endTransaction()``, because there is no transaction open). | ++----------------------------------+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ +| *RS\_RET\_DEFER\_COMMIT* | The record has been processed, but is not yet committed. This is the expected state for transactional-aware plugins. | ++----------------------------------+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ +| *RS\_RET\_PREVIOUS\_COMMITTED* | The **previous** record inside the batch has been committed, but the current one not yet. This state is introduced to support sources that fill up buffers and commit once a buffer is completely filled. That may occur halfway in the next record, so it may be important to be able to tell the engine the everything up to the previous record is committed | ++----------------------------------+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ + +Note that the typical **calling cycle** is ``beginTransaction()``, +followed by *n* times ``doAction()`` followed by ``endTransaction()``. +However, if either ``beginTransaction()`` or ``doAction()`` return back +an error state (including RS\_RET\_SUSPENDED), then the transaction is +considered aborted. In result, the remaining calls in this cycle (e.g. +``endTransaction()``) are never made and a new cycle (starting with +``beginTransaction()`` is begun when processing resumes. So an output +plugin must expect and handle those partial cycles gracefully. + +**The question remains how can a plugin know if the core supports +batching?** First of all, even if the engine would not know it, the +plugin would return with RS\_RET\_DEFER\_COMMIT, what then would be +treated as an error by the engine. This would effectively disable the +output, but cause no further harm (but may be harm enough in itself). + +The real solution is to enable the plugin to query the rsyslog core if +this feature is supported or not. At the time of the introduction of +batching, no such query-interface exists. So we introduce it with that +release. What the means is if a rsyslog core can not provide this query +interface, it is a core that was build before batching support was +available. So the absence of a query interface indicates that the +transactional interface is not available. One might now be tempted to +think there is no need to do the actual check, but is is recommended to +ask the rsyslog engine explicitly if the transactional interface is +present and will be honored. This enables us to create versions in the +future which have, for whatever reason we do not yet know, no support +for this interface. + +The logic to do these checks is contained in the ``INITChkCoreFeature`` +macro, which can be used as follows: + +:: + + INITChkCoreFeature(bCoreSupportsBatching, CORE_FEATURE_BATCHING); + +Here, bCoreSupportsBatching is a plugin-defined integer which after +execution is 1 if batches (and thus the transactional interface) is +supported and 0 otherwise. CORE\_FEATURE\_BATCHING is the feature we are +interested in. Future versions of rsyslog may contain additional +feature-test-macros (you can see all of them in ./runtime/rsyslog.h). + +Note that the ompsql output plugin supports transactional mode in a +hybrid way and thus can be considered good example code. + +Open Issues +----------- + +- Processing errors handling +- reliable re-queue during error handling and queue termination + +Licensing +~~~~~~~~~ + +From the rsyslog point of view, plugins constitute separate projects. As +such, we think plugins are not required to be compatible with GPLv3. +However, this is not legal advise. If you intend to release something +under a non-GPLV3 compatible license it is probably best to consult with +your lawyer. + +Most importantly, and this is definite, the rsyslog team does not expect +or require you to contribute your plugin to the rsyslog project (but of +course we are happy if you do). diff --git a/source/development/dev_queue.rst b/source/development/dev_queue.rst new file mode 100644 index 0000000..fb5a286 --- /dev/null +++ b/source/development/dev_queue.rst @@ -0,0 +1,299 @@ +The rsyslog queue object +======================== + +This page reflects the status as of 2008-01-17. The documentation is +still incomplete. Target audience is developers and users who would like +to get an in-depth understanding of queues as used in +`rsyslog <http://www.rsyslog.com/>`_. + +**Please note that this document is outdated and does not longer reflect +the specifics of the queue object. However, I have decided to leave it +in the doc set, as the overall picture provided still is quite OK. I +intend to update this document somewhat later when I have reached the +"store-and-forward" milestone.** + +Some definitions +---------------- + +A queue is DA-enabled if it is configured to use disk-assisted mode when +there is need to. A queue is in DA mode (or DA run mode), when it +actually runs disk assisted. + +Implementation Details +---------------------- + +Disk-Assisted Mode +~~~~~~~~~~~~~~~~~~ + +Memory-Type queues may utilize disk-assisted (DA) mode. DA mode is +enabled whenever a queue file name prefix is provided. This is called +DA-enabled mode. If DA-enabled, the queue operates as a regular memory +queue until a high water mark is reached. If that happens, the queue +activates disk assistance (called "runs disk assisted" or "runs DA" - +you can find that often in source file comments). To do so, it creates a +helper queue instance (the DA queue). At that point, there are two +queues running - the primary queue's consumer changes to a +shuffle-to-DA-queue consumer and the original primary consumer is +assigned to the DA queue. Existing and new messages are spooled to the +disk queue, where the DA worker takes them from and passes them for +execution to the actual consumer. In essence, the primary queue has now +become a memory buffer for the DA queue. The primary queue will be +drained until a low water mark is reached. At that point, processing is +held. New messages enqueued to the primary queue will not be processed +but kept in memory. Processing resumes when either the high water mark +is reached again or the DA queue indicates it is empty. If the DA queue +is empty, it is shut down and processing of the primary queue continues +as a regular in-memory queue (aka "DA mode is shut down"). The whole +thing iterates once the high water mark is hit again. + +There is one special case: if the primary queue is shut down and could +not finish processing all messages within the configured timeout +periods, the DA queue is instantiated to take up the remaining messages. +These will be preserved and be processed during the next run. During +that period, the DA queue runs in "enqueue-only" mode and does not +execute any consumer. Draining the primary queue is typically very fast. +If that behaviour is not desired, it can be turned of via parameters. In +that case, any remaining in-memory messages are lost. + +Due to the fact that when running DA two queues work closely together +and worker threads (including the DA worker) may shut down at any time +(due to timeout), processing synchronization and startup and shutdown is +somewhat complex. I'll outline the exact conditions and steps down here. +I also do this so that I know clearly what to develop to, so please be +patient if the information is a bit too in-depth ;) + +DA Run Mode Initialization +~~~~~~~~~~~~~~~~~~~~~~~~~~ + +Three cases: + +#. any time during queueEnqObj() when the high water mark is hit +#. at queue startup if there is an on-disk queue present (presence of QI + file indicates presence of queue data) +#. at queue shutdown if remaining in-memory data needs to be persisted + to disk + +In **case 1**, the worker pool is running. When switching to DA mode, +all regular workers are sent termination commands. The DA worker is +initiated. Regular workers may run in parallel to the DA worker until +they terminate. Regular workers shall terminate as soon as their current +consumer has completed. They shall not execute the DA consumer. + +In **case 2**, the worker pool is not yet running and is NOT started. +The DA worker is initiated. + +In **case 3**, the worker pool is already shut down. The DA worker is +initiated. The DA queue runs in enqueue-only mode. + +In all cases, the DA worker starts up and checks if DA mode is already +fully initialized. If not, it initializes it, what most importantly +means construction of the queue. + +Then, regular worker processing is carried out. That is, the queue +worker will wait on empty queue and terminate after an timeout. However, +If any message is received, the DA consumer is executed. That consumer +checks the low water mark. If the low water mark is reached, it stops +processing until either the high water mark is reached again or the DA +queue indicates it is empty (there is a pthread\_cond\_t for this +synchronization). + +In theory, a **case-2** startup could lead to the worker becoming +inactive and terminating while waiting on the primary queue to fill. In +practice, this is highly unlikely (but only for the main message queue) +because rsyslog issues a startup message. HOWEVER, we can not rely on +that, it would introduce a race. If the primary rsyslog thread (the one +that issues the message) is scheduled very late and there is a low +inactivity timeout for queue workers, the queue worker may terminate +before the startup message is issued. And if the on-disk queue holds +only a few messages, it may become empty before the DA worker is +re-initiated again. So it is possible that the DA run mode termination +criteria occurs while no DA worker is running on the primary queue. + +In cases 1 and 3, the DA worker can never become inactive without +hitting the DA shutdown criteria. In **case 1**, it either shuffles +messages from the primary to the DA queue or it waits because it has the +hit low water mark. + +In **case 3**, it always shuffles messages between the queues (because, +that's the sole purpose of that run). In order for this to happen, the +high water mark has been set to the value of 1 when DA run mode has been +initialized. This ensures that the regular logic can be applied to drain +the primary queue. To prevent a hold due to reaching the low water mark, +that mark must be changed to 0 before the DA worker starts. + +DA Run Mode Shutdown +~~~~~~~~~~~~~~~~~~~~ + +In essence, DA run mode is terminated when the DA queue is empty and the +primary worker queue size is below the high water mark. It is also +terminated when the primary queue is shut down. The decision to switch +back to regular (non-DA) run mode is typically made by the DA worker. If +it switches, the DA queue is destructed and the regular worker pool is +restarted. In some cases, the queue shutdown process may initiate the +"switch" (in this case more or less a clean shutdown of the DA queue). + +One might think that it would be more natural for the DA queue to detect +being idle and shut down itself. However, there are some issues +associated with that. Most importantly, all queue worker threads need to +be shut down during queue destruction. Only after that has happened, +final destruction steps can happen (else we would have a myriad of +races). However, it is the DA queues worker thread that detects it is +empty (empty queue detection always happens at the consumer side and +must so). That would lead to the DA queue worker thread to initiate DA +queue destruction which in turn would lead to that very same thread +being canceled (because workers must shut down before the queue can be +destructed). Obviously, this does not work out (and I didn't even +mention the other issues - so let's forget about it). As such, the +thread that enqueues messages must destruct the queue - and that is the +primary queue's DA worker thread. + +There are some subtleties due to thread synchronization and the fact +that the DA consumer may not be running (in a **case-2 startup**). So it +is not trivial to reliably change the queue back from DA run mode to +regular run mode. The priority is a clean switch. We accept the fact +that there may be situations where we cleanly shut down DA run mode, +just to re-enable it with the very next message being enqueued. While +unlikely, this will happen from time to time and is considered perfectly +legal. We can't predict the future and it would introduce too great +complexity to try to do something against that (that would most probably +even lead to worse performance under regular conditions). + +The primary queue's DA worker thread may wait at two different places: + +#. after reaching the low water mark and waiting for either high water + or DA queue empty +#. at the regular pthread\_cond\_wait() on an empty primary queue + +Case 2 is unlikely, but may happen (see info above on a case 2 startup). + +**The DA worker may also not wait at all,** because it is actively +executing and shuffling messages between the queues. In that case, +however, the program flow passes both of the two wait conditions but +simply does not wait. + +**Finally, the DA worker may be inactive**\ (again, with a case-2 +startup). In that case no work(er) at all is executed. Most importantly, +without the DA worker being active, nobody will ever detect the need to +change back to regular mode. If we have this situation, the very next +message enqueued will cause the switch, because then the DA run mode +shutdown criteria is met. However, it may take close to eternal for this +message to arrive. During that time, disk and memory resources for the +DA queue remain allocated. This also leaves processing in a sub-optimal +state and it may take longer than necessary to switch back to regular +queue mode when a message burst happens. In extreme cases, this could +even lead to shutdown of DA run mode, which takes so long that the high +water mark is passed and DA run mode is immediately re-initialized - +while with an immediate switch, the message burst may have been able to +be processed by the in-memory queue without DA support. + +So in short, it is desirable switch to regular run mode as soon as +possible. To do this, we need an active DA worker. The easy solution is +to initiate DA worker startup from the DA queue's worker once it detects +empty condition. To do so, the DA queue's worker must call into a "*DA +worker startup initiation*\ " routine inside the main queue. As a +reminder, the DA worker will most probably not receive the "DA queue +empty" signal in that case, because it will be long sent (in most cases) +before the DA worker even waits for it. So **it is vital that DA run +mode termination checks be done in the DA worker before it goes into any +wait condition**. + +Please note that the "*DA worker startup initiation*\ " routine may be +called concurrently from multiple initiators. **To prevent a race, it +must be guarded by the queue mutex**\ and return without any action (and +no error code!) if the DA worker is already initiated. + +All other cases can be handled by checking the termination criteria +immediately at the start of the worker and then once again for each run. +The logic follows this simplified flow diagram: + +.. |image0| image:: queueWorkerLogic.jpg + +Some of the more subtle aspects of worker processing (e.g. enqueue +thread signaling and other fine things) have been left out in order to +get the big picture. What is called "check DA mode switchback..." right +after "worker init" is actually a check for the worker's termination +criteria. Typically, **the worker termination criteria is a shutdown +request**. However, **for a DA worker, termination is also requested if +the queue size is below the high water mark AND the DA queue is empty**. +There is also a third termination criteria and it is not even on the +chart: that is the inactivity timeout, which exists in all modes. Note +that while the inactivity timeout shuts down a thread, it logically does +not terminate the worker pool (or DA worker): workers are restarted on +an as-needed basis. However, inactivity timeouts are very important +because they require us to restart workers in some situations where we +may expect a running one. So always keep them on your mind. + +Queue Destruction +~~~~~~~~~~~~~~~~~ + +Now let's consider **the case of destruction of the primary +queue.**\ During destruction, our focus is on loosing as few messages as +possible. If the queue is not DA-enabled, there is nothing but the +configured timeouts to handle that situation. However, with a DA-enabled +queue there are more options. + +If the queue is DA-enabled, it may be *configured to persist messages to +disk before it is terminated*. In that case, loss of messages never +occurs (at the price of a potentially lengthy shutdown). Even if that +setting is not applied, the queue should drain as many messages as +possible to the disk. For that reason, it makes no sense to wait on a +low water mark. Also, if the queue is already in DA run mode, it does +not make any sense to switch back to regular run mode during termination +and then try to process some messages via the regular consumer. It is +much more appropriate the try completely drain the queue during the +remaining timeout period. For the same reason, it is preferred that no +new consumers be activated (via the DA queue's worker), as they only +cost valuable CPU cycles and, more importantly, would potentially be +long(er)-running and possibly be needed to be cancelled. To prevent all +of that, **queue parameters are changed for DA-enabled queues:** the +high water mark is to 1 and the low water mark to 0 on the primary +queue. The DA queue is commanded to run in enqueue-only mode. If the +primary queue is *configured to persist messages to disk before it is +terminated*, its SHUTDOWN timeout is changed to to eternal. These +parameters will cause the queue to drain as much as possible to disk +(and they may cause a case 3 DA run mode initiation). Please note that +once the primary queue has been drained, the DA queue's worker will +automatically switch back to regular (non-DA) run mode. **It must be +ensured that no worker cancellation occurs during that switchback**. +Please note that the queue may not switch back to regular run mode if it +is not *configured to persist messages to disk before it is terminated*. +In order to apply the new parameters, **worker threads must be +awakened.** Remember we may not be in DA run mode at this stage. In that +case, the regular workers must be awakened, which then will switch to DA +run mode. No worker may be active, in that case one must be initiated. +If in DA run mode and the DA worker is inactive, the "*DA worker +startup initiation*\ " must be called to activate it. That routine +ensures only one DA worker is started even with multiple concurrent +callers - this may be the case here. The DA queue's worker may have +requested DA worker startup in order to terminate on empty queue (which +will probably not be honored as we have changed the low water mark). + +After all this is done, the queue destructor requests termination of the +queue's worker threads. It will use the normal timeouts and potentially +cancel too-long running worker threads. **The shutdown process must +ensure that all workers reach running state before they are commanded to +terminate**. Otherwise it may run into a race condition that could lead +to a false shutdown with workers running asynchronously. As a few +workers may have just been started to initialize (to apply new parameter +settings), the probability for this race condition is extremely high, +especially on single-CPU systems. + +After all workers have been shut down (or cancelled), the queue may +still be in DA run mode. If so, this must be terminated, which now can +simply be done by destructing the DA queue object. This is not a real +switchback to regular run mode, but that doesn't matter because the +queue object will soon be gone away. + +Finally, the queue is mostly shut down and ready to be actually +destructed. As a last try, the queuePersists() entry point is called. It +is used to persists a non-DA-enabled queue in whatever way is possible +for that queue. There may be no implementation for the specific queue +type. Please note that this is not just a theoretical construct. This is +an extremely important code path when the DA queue itself is destructed. +Remember that it is a queue object in its own right. The DA queue is +obviously not DA-enabled, so it calls into queuePersists() during its +destruction - this is what enables us to persist the disk queue! + +After that point, left over queue resources (mutexes, dynamic memory, +...) are freed and the queue object is actually destructed. + diff --git a/source/development/dev_testbench.rst b/source/development/dev_testbench.rst new file mode 100644 index 0000000..40721c5 --- /dev/null +++ b/source/development/dev_testbench.rst @@ -0,0 +1,20 @@ +writing rsyslog tests +===================== + +The rsyslog testbench is executed via `make check` or `make distcheck`. For details, on +these modes, see the GNU autotools documentation. The most important thing is that +the `make distcheck` test execution environment is considerably different from its +`make check` counterpart. The rsyslog testbench is crafted to handle both cases and +does so with the (intensive) use of environment variables. + +The rsyslog testbench aims to support parallel tests. This is not yet fully implemented, +but we are working towards that goal. This has a number of implications/requirements: + +* all file names, ports, etc need to be unique +* the diag.sh framework supports auto-generation capabilities to support this: + use `${RSYSLOG_DYNNAME}` a prefix for all files you generate. For the frequently + used files, the framework already defines `${RSYSLOG_OUT_LOG}` and `${RSYSLOG_OUT_LOG2}` + + +When writing new tests, it is in general advisable to copy an existing test and change +it. This also helps you get requirements files. diff --git a/source/development/generic_design.rst b/source/development/generic_design.rst new file mode 100644 index 0000000..6c02ad6 --- /dev/null +++ b/source/development/generic_design.rst @@ -0,0 +1,146 @@ +Generic design of a syslogd +--------------------------- + +Written 2007-04-10 by `Rainer Gerhards <https://rainer.gerhards.net>`_ + +The text below describes a generic approach on how a syslogd can be +implemented. I created this description for some other project, where it +was not used. Instead of throwing it away, I thought it would be a good +addition to the rsyslog documentation. While rsyslog differs in details +from the description below, it is sufficiently close to it. Further +development of rsyslog will probably match it even closer to the +description. + +If you intend to read the rsyslog source code, I recommend reading this +document here first. You will not find the same names and not all of the +concepts inside rsyslog. However, I think your understanding will +benefit from knowing the generic architecture. + +:: + + + +-----------------+ + | "remote" PLOrig | + +-----------------+ + | + I +--------+-----+-----+ +-----+-------+------+-----+ + P | PLOrig | GWI | ... | | GWO | Store | Disc | ... | + C +--------+-----+-----+ +-----+-------+------+-----+ + | | ^ + v v | + +--------------+ +------------+ +--------------+ + | PLGenerator | | RelayEng | | CollectorEng | + +--------------+ +------------+ +--------------+ + | ^ ^ + | | | + v v | + +-------------+ +------------+ +--------------+ + | PLG Ext | | RelEng Ext | | CollcEng Ext | + +-------------+ +------------+ +--------------+ + | ^ ^ + | | | + v v | + +--------------------------------------------------------------+ + | Message Router | + +--------------------------------------------------------------+ + | ^ + v | + +--------------------------------------------------------------+ + | Message CoDec (e.g. RFC 3164, RFCYYYY) | + +--------------------------------------------------------------+ + | ^ + v | + +---------------------+-----------------------+----------------+ + | transport UDP | transport TLS | ... | + +---------------------+-----------------------+----------------+ + + Generic Syslog Application Architecture + +- A "syslog application" is an application whose purpose is the + processing of syslog messages. It may be part of a larger application + with a broader purpose. An example: a database application might come + with its own syslog send subsystem and not go through a central + syslog application. In the sense of this document, that application + is called a "syslog application" even though a casual observer might + correctly call it a database application and may not even know that + it supports sending of syslog messages. +- Payload is the information that is to be conveyed. Payload by itself + may have any format and is totally independent from to format + specified in this document. The "Message CoDec" of the syslog + application will bring it into the required format. +- Payload Originators ("PLOrig") are the original creators of payload. + Typically, these are application programs. +- A "Remote PLOrig" is a payload originator residing in a different + application than the syslog application itself. That application may + reside on a different machine and may talk to the syslog application + via RPC. +- A "PLOrig" is a payload originator residing within the syslog + application itself. Typically, this PLOrig emits syslog application + startup, shutdown, error and status log messages. +- A "GWI" is a inbound gateway. For example, a SNMP-to-syslog gateway + may receive SNMP messages and translate them into syslog. +- The ellipsis after "GWI" indicates that there are potentially a + variety of different other ways to originally generate payload. +- A "PLGenerator" is a payload generator. It takes the information from + the payload-generating source and integrates it into the syslog + subsystem of the application. This is a highly theoretical concept. + In practice, there may not actually be any such component. Instead, + the payload generators (or other parts like the GWI) may talk + directly to the syslog subsystem. Conceptually, the "PLGenerator" is + the first component where the information is actually syslog content. +- A "PLG Ext" is a payload generator extension. It is used to modify + the syslog information. An example of a "PLG Ext" might be the + addition of cryptographic signatures to the syslog information. +- A "Message Router" is a component that accepts in- and outbound + syslog information and routes it to the proper next destination + inside the syslog application. The routing information itself is + expected to be learnt by operator configuration. +- A "Message CoDec" is the message encoder/decoder. The encoder takes + syslog information and encodes them into the required format + for a syslog message. The decoder takes a syslog message and decodes + it into syslog information. Codecs for multiple syslog formats may be + present inside a single syslog application. +- A transport (UDP, TLS, yet-to-be-defined ones) sends and receives + syslog messages. Multiple transports may be used by a single + syslog application at the same time. A single transport instance may + be used for both sending and receiving. Alternatively, a single + instance might be used for sending and receiving exclusively. + Multiple instances may be used for different listener ports and + receivers. +- A "RelayEng" is the relaying engine. It provides functionality + necessary for receiving syslog information and sending it to another + syslog application. +- A "RelEng Ext" is an extension that processes syslog information as + it enters or exits a RelayEng. An example of such a component might + be a relay cryptographically signing received syslog messages. Such a + function might be useful to guarantee authenticity starting from a + given point inside a relay chain. +- A "CollectorEng" is a collector engine. At this component, syslog + information leaves the syslog system and is translated into some + other form. After the CollectorEng, the information is no longer + defined to be of native syslog type. +- A "CollcEng Ext" is a collector engine extension. It modifies syslog + information before it is passed on to the CollectorEng. An example + for this might be the verification of cryptographically signed syslog + message information. Please note that another implementation approach + would be to do the verification outside of the syslog application or + in a stage after "CollectorEng". +- A "GWO" is an outbound gateway. An example of this might be the + forwarding of syslog information via SNMP or SMTP. Please note that + when a GWO directly connects to a GWI on a different syslog + application, no native exchange of syslog information takes place. + Instead, the native protocol of these gateways (e.g. SNMP) is used. + The syslog information is embedded inside that protocol. Depending on + protocol and gateway implementation, some of the native syslog + information might be lost. +- A "Store" is any way to persistently store the extracted syslog + information, e.g. to the file system or to a data base. +- "Disc" means the discarding of messages. Operators often find it + useful to discard noise messages and so most syslog applications + contain a way to do that. +- The ellipsis after "Disc" indicates that there are potentially a + variety of different other ways to consume syslog information. +- There may be multiple instances of each of the described components + in a single syslog application. +- A syslog application is made up of all or some of the above mentioned + components. diff --git a/source/development/index.rst b/source/development/index.rst new file mode 100644 index 0000000..02a5cc0 --- /dev/null +++ b/source/development/index.rst @@ -0,0 +1,7 @@ +Development +=========== + +.. toctree:: + :glob: + + * diff --git a/source/development/queueWorkerLogic.jpg b/source/development/queueWorkerLogic.jpg Binary files differnew file mode 100644 index 0000000..fb143c4 --- /dev/null +++ b/source/development/queueWorkerLogic.jpg diff --git a/source/direct_queue0.png b/source/direct_queue0.png Binary files differnew file mode 100644 index 0000000..6d1b373 --- /dev/null +++ b/source/direct_queue0.png diff --git a/source/direct_queue1.png b/source/direct_queue1.png Binary files differnew file mode 100644 index 0000000..503f815 --- /dev/null +++ b/source/direct_queue1.png diff --git a/source/direct_queue2.png b/source/direct_queue2.png Binary files differnew file mode 100644 index 0000000..cbb99af --- /dev/null +++ b/source/direct_queue2.png diff --git a/source/direct_queue3.png b/source/direct_queue3.png Binary files differnew file mode 100644 index 0000000..cc49299 --- /dev/null +++ b/source/direct_queue3.png diff --git a/source/direct_queue_directq.png b/source/direct_queue_directq.png Binary files differnew file mode 100644 index 0000000..c5d8769 --- /dev/null +++ b/source/direct_queue_directq.png diff --git a/source/direct_queue_rsyslog.png b/source/direct_queue_rsyslog.png Binary files differnew file mode 100644 index 0000000..6150222 --- /dev/null +++ b/source/direct_queue_rsyslog.png diff --git a/source/direct_queue_rsyslog2.png b/source/direct_queue_rsyslog2.png Binary files differnew file mode 100644 index 0000000..807b064 --- /dev/null +++ b/source/direct_queue_rsyslog2.png diff --git a/source/examples/high_performance.rst b/source/examples/high_performance.rst new file mode 100644 index 0000000..665f3d0 --- /dev/null +++ b/source/examples/high_performance.rst @@ -0,0 +1,76 @@ +Receiving massive amounts of messages with high performance +=========================================================== + +Use Case +-------- + +You are receiving syslog messages via UDP and or TCP at a very high data rate. +You want to tune the system so that it can process as many messages as +possible. All messages shall be written to a single output file. + +Sample Configuration +-------------------- + +:: + + # load required modules + module(load="imudp" threads="2" + timeRequery="8" batchSize="128") + module(load="imptcp" threads="3") + + # listeners + # repeat blocks if more listeners are needed + # alternatively, use array syntax: + # port=["514","515",...] + input(type="imudp" port="514" + ruleset="writeRemoteData") + input(type="imptcp" port="10514" + ruleset="writeRemoteData") + + # now define our ruleset, which also includes + # threading and queue parameters. + ruleset(name="writeRemoteData" + queue.type="fixedArray" + queue.size="250000" + queue.dequeueBatchSize="4096" + queue.workerThreads="4" + queue.workerThreadMinimumMessages="60000" + ) { + action(type="omfile" file="/var/log/remote.log" + ioBufferSize="64k" flushOnTXEnd="off" + asyncWriting="on") + } + +Notes on the suggested config +----------------------------- +It is highly suggested to use a recent enough Linux kernel that supports +the **recvmmsg()** system call. This system call improves UDP reception +speed and decreases overall system CPU utilization. + +We use the **imptcp** module for tcp input, as it uses more optimal +results. Note, however, that it is only available on Linux and does +currently *not* support TLS. If **imptcp** cannot be used, use +**imtcp** instead (this will be a bit slower). + +When writing to the output file, we use buffered mode. This means that +full buffers are written, but during processing file lines are not +written until the buffer is full (and thus may be delayed) and also +incomplete lines are written (at buffer boundary). When the file is closed +(rsyslogd stop or HUP), the buffer is completely flushed. As this is +a high-traffic use case, we assume that buffered mode does not cause +any concerns. + +Suggested User Performance Testing +---------------------------------- +Each environment is a bit different. +Depending on circumstances, the **imudp** module parameters may not be +optimal. In order to obtain best performance, it is suggested to measure +performance level with two to four threads and somewhat lower and higher +batchSize. Note that these parameters affect each other. The values given +in the config above should usually work well in *high-traffic* environments. +They are sub-optimal for low to medium traffic environments. + +See Also +-------- +imptcp, imtcp, imudp, ruleset() + diff --git a/source/examples/index.rst b/source/examples/index.rst new file mode 100644 index 0000000..7a39384 --- /dev/null +++ b/source/examples/index.rst @@ -0,0 +1,7 @@ +Example Use Cases +================= + +.. toctree:: + :maxdepth: 2 + + high_performance diff --git a/source/faq/difference_queues.rst b/source/faq/difference_queues.rst new file mode 100644 index 0000000..458dc59 --- /dev/null +++ b/source/faq/difference_queues.rst @@ -0,0 +1,34 @@ +What is the difference between the main_queue and a queue with a ruleset tied to an input? +========================================================================================== + +A queue on a ruleset tied to an input replaces the main queue for that input. +The only difference is the higher default size of the main queue. + +If an input bounded ruleset does not have a queue defined, what default does it have? +------------------------------------------------------------------------------------- + +Rulesets without a queue on them use the main queue as a default. + +What is the recommended way to use several inputs? Should there be a need to define a queue for the rulesets? +------------------------------------------------------------------------------------------------------------- + +If you are going to do the same thing with all logs, then they should share a ruleset. + +If you are doing different things with different logs, then they should have +different rulesets. + +For example take a system where the default ruleset processes things and sends +them over the network to the nearest relay system. All systems have this same +default ruleset. +Then in the relay systems there is a ruleset which is tied to both TCP and UDP +listeners, and it receives the messages from the network, cleans them up, +and sends them on. +There is no mixing of these two processing paths, so having them as completely +separate paths with rulesets tied to the inputs and queues on the rulesets +makes sense. + +A queue on a ruleset tied to one or more inputs can be thought of as a separate +instance of rsyslog, which processes those logs. + + +Credits: davidelang diff --git a/source/faq/index.rst b/source/faq/index.rst new file mode 100644 index 0000000..29e7627 --- /dev/null +++ b/source/faq/index.rst @@ -0,0 +1,7 @@ +FAQ +=== + +.. toctree:: + :maxdepth: 1 + + difference_queues diff --git a/source/features.rst b/source/features.rst new file mode 100644 index 0000000..b7038d2 --- /dev/null +++ b/source/features.rst @@ -0,0 +1,148 @@ +RSyslog - Features +================== + +**This page lists both current features as well as those being +considered for future versions of rsyslog.** If you think a feature is +missing, drop `Rainer <mailto:rgerhards@adiscon.com>`_ a note. Rsyslog +is a vital project. Features are added each few days. If you would like +to keep up of what is going on, you can also subscribe to the `rsyslog +mailing list <http://lists.adiscon.net/mailman/listinfo/rsyslog>`_. + +A better structured feature list is now contained in our `rsyslog vs. +syslog-ng comparison <rsyslog_ng_comparison.html>`_. Probably that page +will replace this one in the future. + +Current Features +---------------- + +- native support for `writing to MySQL databases <rsyslog_mysql.html>`_ +- native support for writing to Postgres databases +- direct support for Firebird/Interbase, OpenTDS (MS SQL, Sybase), + SQLite, Ingres, Oracle, and mSQL via libdbi, a database abstraction + layer (almost as good as native) +- native support for `sending mail messages <ommail.html>`_ (first seen + in 3.17.0) +- support for (plain) tcp based syslog - much better reliability +- support for sending and receiving compressed syslog messages +- support for on-demand on-disk spooling of messages that can not be + processed fast enough (a great feature for `writing massive amounts + of syslog messages to a database <rsyslog_high_database_rate.html>`_) +- support for selectively `processing messages only during specific + timeframes <http://wiki.rsyslog.com/index.php/OffPeakHours>`_ and + spooling them to disk otherwise +- ability to monitor text files and convert their contents into syslog + messages (one per line) +- ability to configure backup syslog/database servers - if the primary + fails, control is switched to a prioritized list of backups +- support for receiving messages via reliable `RFC + 3195 <http://www.monitorware.com/Common/en/glossary/rfc3195.php>`_ + delivery (a bit clumsy to build right now...) +- ability to generate file names and directories (log targets) + dynamically, based on many different properties +- control of log output format, including ability to present channel + and priority as visible log data +- good timestamp format control; at a minimum, ISO 8601/RFC 3339 + second-resolution UTC zone +- ability to reformat message contents and work with substrings +- support for log files larger than 2gb +- support for file size limitation and automatic rollover command + execution +- support for running multiple rsyslogd instances on a single machine +- support for `TLS-protected syslog <rsyslog_tls.html>`_ (both + `natively <rsyslog_tls.html>`_ and via + `stunnel <rsyslog_stunnel.html>`_) +- ability to filter on any part of the message, not just facility and + severity +- ability to use regular expressions in filters +- support for discarding messages based on filters +- ability to execute shell scripts on received messages +- control of whether the local hostname or the hostname of the origin + of the data is shown as the hostname in the output +- ability to preserve the original hostname in NAT environments and + relay chains +- ability to limit the allowed network senders +- powerful BSD-style hostname and program name blocks for easy + multi-host support +- massively multi-threaded with dynamic work thread pools that start up + and shut themselves down on an as-needed basis (great for high log + volume on multicore machines) +- very experimental and volatile support for + `syslog-protocol <syslog_protocol.html>`_ compliant messages (it is + volatile because standardization is currently underway and this is a + proof-of-concept implementation to aid this effort) +- world's first implementation of syslog-transport-tls +- the sysklogd's klogd functionality is implemented as the *imklog* + input plug-in. So rsyslog is a full replacement for the sysklogd + package +- support for IPv6 +- ability to control repeated line reduction ("last message repeated n + times") on a per selector-line basis +- supports sub-configuration files, which can be automatically read + from directories. Includes are specified in the main configuration + file +- supports multiple actions per selector/filter condition +- MySQL and Postgres SQL functionality as a dynamically loadable + plug-in +- modular design for inputs and outputs - easily extensible via custom + plugins +- an easy-to-write to plugin interface +- ability to send SNMP trap messages +- ability to filter out messages based on sequence of arrival +- support for comma-separated-values (CSV) output generation (via the + "csv" property replace option). The CSV format supported is that from + RFC 4180. +- support for arbitrary complex boolean, string and arithmetic + expressions in message filters + +World's first +------------- + +Rsyslog has an interesting number of "world's firsts" - things that were +implemented for the first time ever in rsyslog. Some of them are still +features not available elsewhere. + +- world's first implementation of IETF I-D syslog-protocol (February + 2006, version 1.12.2 and above), now RFC5424 +- world's first implementation of dynamic syslog on-the-wire + compression (December 2006, version 1.13.0 and above) +- world's first open-source implementation of a disk-queueing syslogd + (January 2008, version 3.11.0 and above) +- world's first implementation of IETF I-D syslog-transport-tls (May + 2008, version 3.19.0 and above) + +Upcoming Features +----------------- + +The list below is something like a repository of ideas we'd like to +implement. Features on this list are typically NOT scheduled for +immediate inclusion. + +**Note that we also maintain a `list of features that are looking for +sponsors <http://www.rsyslog.com/sponsor_feature>`_. If you are +interested in any of these features, or any other feature, you may +consider sponsoring the implementation. This is also a great way to show +your commitment to the open source community. Plus, it can be +financially attractive: just think about how much less it may be to +sponsor a feature instead of purchasing a commercial implementation. +Also, the benefit of being recognized as a sponsor may even drive new +customers to your business!** + +- port it to more \*nix variants (eg AIX and HP UX) - this needs + volunteers with access to those machines and knowledge +- pcre filtering - maybe (depending on feedback) - simple regex + already partly added. So far, this seems sufficient so that there is + no urgent need to do pcre. If done, it will be a loadable + RainerScript function. +- support for `RFC + 3195 <http://www.monitorware.com/Common/en/glossary/rfc3195.php>`_ as + a sender - this is currently unlikely to happen, because there is no + real demand for it. Any work on RFC 3195 has been suspend until we + see some real interest in it. It is probably much better to use + TCP-based syslog, which is interoperable with a large number of + applications. You may also read my blog post on the future of + liblogging, which contains interesting information about the `future + of RFC 3195 in + rsyslog <http://rgerhards.blogspot.com/2007/09/where-is-liblogging-heading-to.html>`_. + +To see when each feature was added, see the `rsyslog change +log <http://www.rsyslog.com/Topic4.phtml>`_ (online only). diff --git a/source/free_support.rst b/source/free_support.rst new file mode 100644 index 0000000..005a696 --- /dev/null +++ b/source/free_support.rst @@ -0,0 +1,56 @@ +Free Services for Rsyslog +========================= + +*A personal word from Rainer, the lead developer of rsyslog:* + +**The rsyslog community provides ample free support resources. Please +see our** `troubleshooting guide <troubleshooting/index.html>`_ **to get started.** + +Every now and then I receive private mail with support questions. I +appreciate any feedback, but I must limit my resources so that I can +help drive a great logging system forward. + +To do so, I have decided not to reply to unsolicited support emails, at +least not with a solution (but rather a link to this page ;)). I hope +this does not offend you. The reason is quite simple: If I do personal +support, you gain some advantage without contributing something back. +Think about it: if you ask your question on the public forum or mailing +list, others with the same problem can help you and, most importantly, even +years later find your post (and the answer) and get the problem solved. +So by solving your issue in public, you help create a great community +resource and also help your fellow users find solutions quicker. In +the long term, this also contributes to improved code because the more +questions users can find solutions to themselves, the fewer I need to +look at. + +But it becomes even better: the rsyslog community is much broader than +Rainer ;) - there are other helpful members hanging around the public +places. They often answer questions, so that I do not need to look at +them (btw, once again a big "thank you", folks!). And, more important, +those folks have a different background than me. So they often either know +better how to solve your problem (e.g. because it is distro-specific) or +they know how to better phrase it (after all, I like abstract terms and +concepts ;)). So you do yourself a favor if you use the public places. + +An excellent place to go to is the `rsyslog +forum <http://kb.monitorware.com/rsyslog-f40.html>`_ inside the +knowledge base (which in itself is a great place to visit!). For those +used to mailing lists, the `rsyslog mailing +list <http://lists.adiscon.net/mailman/listinfo/rsyslog>`_ also offers +excellent advise. + +**Don't like to post your question in a public place?** Well, then you +should consider purchasing `rsyslog professional +support <http://www.rsyslog.com/professional-services/>`_. The fees are very low and help +fund the project. If you use rsyslog seriously inside a corporate +environment, there is no excuse for not getting one of the support +packages ;) + +Of course, things are different when I ask you to mail me privately. +I'll usually do that when I think it makes sense, for example when we +exchange debug logs. + +I hope you now understand the free support options and the reasoning for +them. I hope I haven't offended you with my words - this is not my +intention. I just needed to make clear why there are some limits on my +responsiveness. Happy logging! diff --git a/source/gssapi.png b/source/gssapi.png Binary files differnew file mode 100644 index 0000000..c82baa5 --- /dev/null +++ b/source/gssapi.png diff --git a/source/historical/index.rst b/source/historical/index.rst new file mode 100644 index 0000000..0b90205 --- /dev/null +++ b/source/historical/index.rst @@ -0,0 +1,13 @@ +Historical Documents +-------------------- +This part of the documentation set contains historical documents +which are still of interest or may be useful in some more exotic +environments. + +.. toctree:: + :maxdepth: 2 + + php_syslog_ng + stunnel + multi_ruleset_legacy_format_samples + module_devel diff --git a/source/historical/module_devel.rst b/source/historical/module_devel.rst new file mode 100644 index 0000000..4306bc3 --- /dev/null +++ b/source/historical/module_devel.rst @@ -0,0 +1,104 @@ +Developing rsyslog modules (outdated) +===================================== + +*Written by `Rainer Gerhards* <https://rainer.gerhards.net>`_ *(2007-07-28)* + +**This document is outdated and primarily contains historical +information. Do not trust it to build code. It currently is under +review.** + +Overview +-------- + +In theory, modules provide input and output, among other functions, in +rsyslog. In practice, modules are only utilized for output in the +current release. The module interface is not yet completed and a moving +target. We do not recommend to write a module based on the current +specification. If you do, please be prepared that future released of +rsyslog will probably break your module. + +A goal of modularization is to provide an easy to use plug-in interface. +However, this goal is not yet reached and all modules must be statically +linked. + +Module "generation" +------------------- + +There is a lot of plumbing that is always the same in all modules. For +example, the interface definitions, answering function pointer queries +and such. To get rid of these laborious things, I generate most of them +automatically from a single file. This file is named module-template.h. +It also contains the current best description of the interface +"specification". + +One thing that can also be achieved with it is the capability to cope +with a rapidly changing interface specification. The module interface is +evolving. Currently, it is far from being finished. As I moved the +monolithic code to modules, I needed (and still need) to make many +"non-clean" code hacks, just to get it working. These things are now +gradually being removed. However, this requires frequent changes to the +interfaces, as things move in and out while working towards a clean +interface. All the interim is necessary to reach the goal. This +volatility of specifications is the number one reasons I currently +advise against implementing your own modules (hint: if you do, be sure +to use module-template.h and be prepared to fix newly appearing and +disappearing data elements). + +Naming Conventions +------------------ + +Source +~~~~~~ + +Output modules, and only output modules, should start with a file name +of "om" (e.g. "omfile.c", "omshell.c"). Similarly, input modules will +use "im" and filter modules "fm". The third character shall not be a +hyphen. + +Module Security +--------------- + +Modules are directly loaded into rsyslog's address space. As such, any +module is provided a big level of trust. Please note that further module +interfaces might provide a way to load a module into an isolated address +space. This, however, is far from being completed. So the number one +rule about module security is to run only code that you know you can +trust. + +To minimize the security risks associated with modules, rsyslog provides +only the most minimalistic access to data structures to its modules. For +that reason, the output modules do not receive any direct pointers to +the selector\_t structure, the syslogd action structures and - most +importantly - the msg structure itself. Access to these structures would +enable modules to access data that is none of their business, creating a +potential security weakness. + +Not having access to these structures also simplifies further queueing +and error handling cases. As we do not need to provide e.g. full access +to the msg object itself, we do not need to serialize and cache it. +Instead, strings needed by the module are created by syslogd and then +the final result is provided to the module. That, for example, means +that in a queued case $NOW is the actual timestamp of when the message +was processed, which may be even days before it being dequeued. Think +about it: If we wouldn't cache the resulting string, $NOW would be the +actual date if the action were suspended and messages queued for some +time. That could potentially result in big confusion. + +It is thought that if an output module actually needs access to the +while msg object, we will (then) introduce a way to serialize it (e.g. +to XML) in the property replacer. Then, the output module can work with +this serialized object. The key point is that output modules never deal +directly with msg objects (and other internal structures). Besides +security, this also greatly simplifies the job of the output module +developer. + +Action Selectors +---------------- + +Modules (and rsyslog) need to know when they are called. For this, there +must an action identification in selector lines. There are two +syntaxes: the single-character syntax, where a single characters +identifies a module (e.g. "\*" for a wall message) and the modules +designator syntax, where the module name is given between colons (e.g. +":ommysql:"). The single character syntax is depreciated and should not +be used for new plugins. diff --git a/source/historical/multi_ruleset_legacy_format_samples.rst b/source/historical/multi_ruleset_legacy_format_samples.rst new file mode 100644 index 0000000..607f79f --- /dev/null +++ b/source/historical/multi_ruleset_legacy_format_samples.rst @@ -0,0 +1,199 @@ +Legacy Format Samples for Multiple Rulesets +=========================================== + +This chapter complements rsyslog's documentation of +:doc:`rulesets <../concepts/multi_ruleset>`. +While the base document focusses on RainerScript format, it +does not provide samples in legacy format. These are included +in this document. + +**Important:** do **not** use legacy ruleset definitions for new +configurations. Especially with rulesets, legacy format is extremely +hard to get right. The information in this page is included in order +to help you understand already existing configurations using the +ruleset feature. We even recommend to convert any such configs +to RainerScript format because of its increased robustness +and simplicity. + +Legacy ruleset support was available starting with version 4.5.0 +and 5.1.1. + +Split local and remote logging +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +Let's say you have a pretty standard system that logs its local messages +to the usual bunch of files that are specified in the default +rsyslog.conf. As an example, your rsyslog.conf might look like this: + +:: + + # ... module loading ... + # The authpriv file has restricted access. + authpriv.* /var/log/secure + # Log all the mail messages in one place. + mail.* /var/log/maillog + # Log cron stuff + cron.* /var/log/cron + # Everybody gets emergency messages + *.emerg * + ... more ... + +Now, you want to add receive messages from a remote system and log these +to a special file, but you do not want to have these messages written to +the files specified above. The traditional approach is to add a rule in +front of all others that filters on the message, processes it and then +discards it: + +:: + + # ... module loading ... + # process remote messages + :fromhost-ip, isequal, "192.0.2.1" /var/log/remotefile + & ~ + # only messages not from 192.0.21 make it past this point + + # The authpriv file has restricted access. + authpriv.* /var/log/secure + # Log all the mail messages in one place. + mail.* /var/log/maillog + # Log cron stuff + cron.* /var/log/cron + # Everybody gets emergency messages + *.emerg * + ... more ... + +Note the tilde character, which is the discard action!. Also note that +we assume that 192.0.2.1 is the sole remote sender (to keep it simple). + +With multiple rulesets, we can simply define a dedicated ruleset for the +remote reception case and bind it to the receiver. This may be written +as follows: + +:: + + # ... module loading ... + # process remote messages + # define new ruleset and add rules to it: + $RuleSet remote + *.* /var/log/remotefile + # only messages not from 192.0.21 make it past this point + + # bind ruleset to tcp listener + $InputTCPServerBindRuleset remote + # and activate it: + $InputTCPServerRun 10514 + + # switch back to the default ruleset: + $RuleSet RSYSLOG_DefaultRuleset + # The authpriv file has restricted access. + authpriv.* /var/log/secure + # Log all the mail messages in one place. + mail.* /var/log/maillog + # Log cron stuff + cron.* /var/log/cron + # Everybody gets emergency messages + *.emerg * + ... more ... + +Here, we need to switch back to the default ruleset after we have +defined our custom one. This is why I recommend a different ordering, +which I find more intuitive. The sample below has it, and it leads to +the same results: + +:: + + # ... module loading ... + # at first, this is a copy of the unmodified rsyslog.conf + # The authpriv file has restricted access. + authpriv.* /var/log/secure + # Log all the mail messages in one place. + mail.* /var/log/maillog + # Log cron stuff + cron.* /var/log/cron + # Everybody gets emergency messages + *.emerg * + ... more ... + # end of the "regular" rsyslog.conf. Now come the new definitions: + + # process remote messages + # define new ruleset and add rules to it: + $RuleSet remote + *.* /var/log/remotefile + + # bind ruleset to tcp listener + $InputTCPServerBindRuleset remote + # and activate it: + $InputTCPServerRun 10514 + +Here, we do not switch back to the default ruleset, because this is not +needed as it is completely defined when we begin the "remote" ruleset. + +Now look at the examples and compare them to the single-ruleset +solution. You will notice that we do **not** need a real filter in the +multi-ruleset case: we can simply use "\*.\*" as all messages now means +all messages that are being processed by this rule set and all of them +come in via the TCP receiver! This is what makes using multiple rulesets +so much easier. + +Split local and remote logging for three different ports +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +This example is almost like the first one, but it extends it a little +bit. While it is very similar, I hope it is different enough to provide +a useful example why you may want to have more than two rulesets. + +Again, we would like to use the "regular" log files for local logging, +only. But this time we set up three syslog/tcp listeners, each one +listening to a different port (in this example 10514, 10515, and 10516). +Logs received from these receivers shall go into different files. Also, +logs received from 10516 (and only from that port!) with "mail.\*" +priority, shall be written into a specif file and **not** be written to +10516's general log file. + +This is the config: + +:: + + # ... module loading ... + # at first, this is a copy of the unmodified rsyslog.conf + # The authpriv file has restricted access. + authpriv.* /var/log/secure + # Log all the mail messages in one place. + mail.* /var/log/maillog + # Log cron stuff + cron.* /var/log/cron + # Everybody gets emergency messages + *.emerg * + ... more ... + # end of the "regular" rsyslog.conf. Now come the new definitions: + + # process remote messages + + #define rulesets first + $RuleSet remote10514 + *.* /var/log/remote10514 + + $RuleSet remote10515 + *.* /var/log/remote10515 + + $RuleSet remote10516 + mail.* /var/log/mail10516 + & ~ + # note that the discard-action will prevent this messag from + # being written to the remote10516 file - as usual... + *.* /var/log/remote10516 + + # and now define listeners bound to the relevant ruleset + $InputTCPServerBindRuleset remote10514 + $InputTCPServerRun 10514 + + $InputTCPServerBindRuleset remote10515 + $InputTCPServerRun 10515 + + $InputTCPServerBindRuleset remote10516 + $InputTCPServerRun 10516 + +Note that the "mail.\*" rule inside the "remote10516" ruleset does not +affect processing inside any other rule set, including the default rule +set. + diff --git a/source/historical/php_syslog_ng.rst b/source/historical/php_syslog_ng.rst new file mode 100644 index 0000000..f8f9f2a --- /dev/null +++ b/source/historical/php_syslog_ng.rst @@ -0,0 +1,156 @@ +Using php-syslog-ng with rsyslog +================================ + +*Written by* `Rainer Gerhards <https://rainer.gerhards.net>`_ *(2005-08-04)* + +Note: it has been reported that this guide is somewhat outdated. Most +importantly, this guide is for the **original** php-syslog-ng and +**cannot** be used for it successor logzilla. Please +use the guide with care. Also, please note that **rsyslog's "native" web frontend +is** `Adiscon LogAnalyzer <http://www.phplogcon.org>`_, which provides best +integration and a lot of extra functionality. + +Abstract +-------- + +**In this paper, I describe how to use** +`php-syslog-ng <http://www.vermeer.org/projects/php-syslog-ng>`_ **with** +`rsyslogd <http://www.rsyslog.com/>`_. Php-syslog-ng is a popular web +interface to syslog data. Its name stem from the fact that it usually +picks up its data from a database created by +`syslog-ng <http://www.balabit.com/products/syslog_ng/>`_ and some +helper scripts. However, there is nothing syslog-ng specific in the +database. With rsyslogd's high customizability, it is easy to write to a +syslog-ng like schema. I will tell you how to do this, enabling you to +use php-syslog-ng as a front-end for rsyslogd - or save the hassle with +syslog-ng database configuration and simply go ahead and use rsyslogd +instead.* + +Overall System Setup +-------------------- + +The setup is pretty straightforward. Basically, php-syslog-ng's +interface to the syslogd is the database. We use the schema that +php-syslog-ng expects and make rsyslogd write to it in its format. +Because of this, php-syslog-ng does not even know there is no syslog-ng +present. + +Setting up the system +--------------------- + +For php-syslog-ng, you can follow its usual setup instructions. Just +skip any steps referring to configure syslog-ng. Make sure you create the +database schema in `MySQL <http://www.mysql.com/>`_. As of this writing, +the expected schema can be created via this script: + +:: + + CREATE DATABASE syslog + USE syslog + CREATE TABLE logs(host varchar(32) default NULL, + facility varchar(10) + default NULL, + priority varchar(10) default NULL, + level varchar(10) default NULL, + tag varchar(10) default NULL, + date date default NULL, + time time default NULL, + program varchar(15) default NULL, + msg text, + seq int(10) unsigned NOT NULL auto_increment, + PRIMARY KEY (seq), + KEY host (host), + KEY seq (seq), + KEY program (program), + KEY time (time), + KEY date (date), + KEY priority (priority), + KEY facility (facility + ) TYPE=MyISAM;`` + +Please note that at the time you are reading this paper, the schema +might have changed. Check for any differences. As we customize rsyslogd +to the schema, it is vital to have the correct one. If this paper is +outdated, `let me know <mailto:rgerhards@adiscon.com>`_ so that I can +fix it. + +Once this schema is created, we simply instruct rsyslogd to store +received data in it. I wont go into too much detail here. If you are +interested in some more details, you might find my paper "`Writing +syslog messages to MySQL <rsyslog_mysql.html>`_\ " worth reading. For +this article, we simply modify `rsyslog.conf <rsyslog_conf.html>`_\ so +that it writes to the database. That is easy. Just these two lines are +needed: + +:: + + $template syslog-ng,"insert into logs(host, facility, priority, tag, date, time, msg) values ('%HOSTNAME%', %syslogfacility%, %syslogpriority%, '%syslogtag%', '%timereported:::date-mysql%', '%timereported:::date-mysql%', '%msg%')", SQL + *.*, mysql-server,syslog,user,pass;syslog-ng + +These are just **two** lines. I have color-coded them so that you see +what belongs together (the colors have no other meaning). The green line +is the actual SQL statement being used to take care of the syslog-ng +schema. Rsyslogd allows you to fully control the statement sent to the +database. This allows you to write to any database format, including +your homegrown one (if you so desire). Please note that there is a small +inefficiency in our current usage: the +``'%timereported:::date-mysql%'`` +property is used for both the time +and the date (if you wonder about what all these funny characters mean, +see the `rsyslogd property replacer manual <property_replacer.html>`_) . +We could have extracted just the date and time parts of the respective +properties. However, this is more complicated and also adds processing +time to rsyslogd's processing (substrings must be extracted). So we take +a full mysql-formatted timestamp and supply it to MySQL. The sql engine +in turn discards the unneeded part. It works pretty well. As of my +understanding, the inefficiency of discarding the unneeded part in MySQL +is lower than the efficiency gain from using the full timestamp in +rsyslogd. So it is most probably the best solution. + +Please note that rsyslogd knows two different timestamp properties: one +is timereported, used here. It is the timestamp from the message itself. +Sometimes that is a good choice, in other cases not. It depends on your +environment. The other one is the timegenerated property. This is the +time when rsyslogd received the message. For obvious reasons, that +timestamp is consistent, even when your devices are in multiple time +zones or their clocks are off. However, it is not "the real thing". It's +your choice which one you prefer. If you prefer timegenerated ... simply +use it ;) + +The line in red tells rsyslogd which messages to log and where to store +it. The "\*.\*" selects all messages. You can use standard syslog +selector line filters here if you do not like to see everything in your +database. The ">" tells rsyslogd that a MySQL connection must be +established. Then, "mysql-server" is the name or IP address of the +server machine, "syslog" is the database name (default from the schema) +and "user" and "pass" are the logon credentials. Use a user with low +privileges, insert into the logs table is sufficient. "syslog-ng" is the +template name and tells rsyslogd to use the SQL statement shown above. + +Once you have made the changes, all you need to do is restart rsyslogd. +Then, you should see syslog messages flow into your database - and show +up in php-syslog-ng. + +Conclusion +---------- + +With minimal effort, you can use php-syslog-ng together with rsyslogd. +For those unfamiliar with syslog-ng, this configuration is probably +easier to set up then switching to syslog-ng. For existing rsyslogd +users, php-syslog-ng might be a nice add-on to their logging +infrastructure. + +Please note that the `MonitorWare +family <http://www.monitorware.com/en/>`_ (to which rsyslog belongs) +also offers a web-interface: `Adiscon LogAnalyzer`_. +From my point of view, obviously, **phpLogCon is the more natural choice +for a web interface to be used together with rsyslog**. It also offers +superb functionality and provides, for example,native display of Windows +event log entries. I have set up a `demo +server <http://demo.phplogcon.org/>`_., You can have a peek at it +without installing anything. + +References and Additional Material +---------------------------------- + +- `php-syslog-ng <http://www.vermeer.org/projects/php-syslog-ng>`_ diff --git a/source/historical/stunnel.rst b/source/historical/stunnel.rst new file mode 100644 index 0000000..90a3e06 --- /dev/null +++ b/source/historical/stunnel.rst @@ -0,0 +1,277 @@ +SSL Encrypting Syslog with Stunnel +================================== + +*Written by* `Rainer Gerhards <https://rainer.gerhards.net>`_ *(2005-07-22)* + +**HISTORICAL DOCUMENT** + +**Note: this is an outdated HISTORICAL document.** A much better description on +`securing syslog with TLS <http://www.rsyslog.com/doc/master/tutorials/tls_cert_summary.html>`_ +is available. + +Abstract +-------- + +**In this paper, I describe how to encrypt** +`syslog <http://www.monitorware.com/en/topics/syslog/>`_ **messages on the +network.** Encryption is vital to keep the confidential content of +syslog messages secure. I describe the overall approach and provide an +HOWTO do it with the help of `rsyslogd <http://www.rsyslog.com>`_ and +`stunnel <http://www.stunnel.org>`_.* + +Please note that starting with rsyslog 3.19.0, `rsyslog provides native +TLS/SSL encryption <rsyslog_tls.html>`_ without the need of stunnel. I +strongly recommend to use that feature instead of stunnel. The stunnel +documentation here is mostly provided for backwards compatibility. New +deployments are advised to use native TLS mode.\ ** + +Background +---------- + +**Syslog is a clear-text protocol. That means anyone with a sniffer can +have a peek at your data.** In some environments, this is no problem at +all. In others, it is a huge setback, probably even preventing +deployment of syslog solutions. Thankfully, there is an easy way to +encrypt syslog communication. I will describe one approach in this +paper. + +The most straightforward solution would be that the syslogd itself +encrypts messages. Unfortunately, encryption is only standardized in +`RFC 3195 <http://www.monitorware.com/Common/en/glossary/rfc3195.php>`_. +But there is currently no syslogd that implements RFC 3195's encryption +features, so this route leads to nothing. Another approach would be to +use vendor- or project-specific syslog extensions. There are a few +around, but the problem here is that they have compatibility issues. +However, there is one surprisingly easy and interoperable solution: +though not standardized, many vendors and projects implement plain tcp +syslog. In a nutshell, plain tcp syslog is a mode where standard syslog +messages are transmitted via tcp and records are separated by newline +characters. This mode is supported by all major syslogd's (both on +Linux/Unix and Windows) as well as log sources (for example, +`EventReporter <http://www.eventreporter.com/en/>`_ for Windows Event +Log forwarding). Plain tcp syslog offers reliability, but it does not +offer encryption in itself. However, since it operates on a tcp stream, +it is now easy to add encryption. There are various ways to do that. In +this paper, I will describe how it is done with stunnel (an other +alternative would be `IPSec <http://en.wikipedia.org/wiki/IPSec>`_, for +example). + +Stunnel is open source and it is available both for Unix/Linux and +Windows. It provides a way to use ssl communication for any non-ssl +aware client and server - in this case, our syslogd. + +Stunnel works much like a wrapper. Both on the client and on the server +machine, tunnel portals are created. The non-ssl aware client and server +software is configured to not directly talk to the remote partner, but +to the local (s)tunnel portal instead. Stunnel, in turn, takes the data +received from the client, encrypts it via ssl, sends it to the remote +tunnel portal and that remote portal sends it to the recipient process +on the remote machine. The transfer to the portals is done via +unencrypted communication. As such, it is vital that the portal and the +respective program that is talking to it are on the same machine, +otherwise data would travel partly unencrypted. Tunneling, as done by +stunnel, requires connection oriented communication. This is why you +need to use tcp-based syslog. As a side-note, you can also encrypt a +plain-text RFC 3195 session via stunnel, though this definitely is not +what the protocol designers had on their mind ;) + +In the rest of this document, I assume that you use rsyslog on both the +client and the server. For the samples, I use +`Debian <http://www.debian.org/>`_. Interestingly, there are some +annoying differences between stunnel implementations. For example, on +Debian a comment line starts with a semicolon (';'). On `Red +Hat <http://www.redhat.com>`_, it starts with a hash sign ('#'). So you +need to watch out for subtle issues when setting up your system. + +Overall System Setup +-------------------- + +In this paper, I assume two machines, one named "client" and the other +named "server". It is obvious that, in practice, you will probably have +multiple clients but only one server. Syslog traffic shall be +transmitted via stunnel over the network. Port 60514 is to be used for +that purpose. The machines are set up as follows: + +**Client** + +- rsyslog forwards message to stunnel local portal at port 61514 +- local stunnel forwards data via the network to port 60514 to its + remote peer + +**Server** + +- stunnel listens on port 60514 to connections from its client peers +- all connections are forwarded to the locally-running rsyslog + listening at port 61514 + +Setting up the system +--------------------- + +For Debian, you need the "stunnel4" package. The "stunnel" package is +the older 3.x release, which will not support the configuration I +describe below. Other distributions might have other names. For example, +on Red Hat it is just "stunnel". Make sure that you install the +appropriate package on both the client and the server. It is also a good +idea to check if there are updates for either stunnel or openssl (which +stunnel uses) - there are often security fixes available and often the +latest fixes are not included in the default package. + +In my sample setup, I use only the bare minimum of options. For example, +I do not make the server check client certificates. Also, I do not talk +much about certificates at all. If you intend to really secure your +system, you should probably learn about certificates and how to manage +and deploy them. This is beyond the scope of this paper. For additional +information, +`http://www.stunnel.org/faq/certs.html <http://www.stunnel.org/faq/certs.html>`_ +is a good starting point. + +You also need to install rsyslogd on both machines. Do this before +starting with the configuration. You should also familiarize yourself +with its configuration file syntax, so that you know which actions you +can trigger with it. Rsyslogd can work as a drop-in replacement for +stock `sysklogd <http://www.infodrom.org/projects/sysklogd/>`_. So if +you know the standard syslog.conf syntax, you do not need to learn any +more to follow this paper. + +Server Setup +~~~~~~~~~~~~ + +At the server, you need to have a digital certificate. That certificate +enables SSL operation, as it provides the necessary crypto keys being +used to secure the connection. Many versions of stunnel come with a +default certificate, often found in /etc/stunnel/stunnel.pem. If you +have it, it is good for testing only. If you use it in production, it is +very easy to break into your secure channel as everybody is able to get +hold of your private key. I didn't find an stunnel.pem on my Debian +machine. I guess the Debian folks removed it because of its insecurity. + +You can create your own certificate with a simple openssl tool - you +need to do it if you have none and I highly recommend to create one in +any case. To create it, cd to /etc/stunnel and type: + + ``openssl req -new -x509 -days 3650 -nodes -out stunnel.pem -keyout stunnel.pem`` + +That command will ask you a number of questions. Provide some answer for +them. If you are unsure, read +`http://www.stunnel.org/faq/certs.html <http://www.stunnel.org/faq/certs.html>`_. +After the command has finished, you should have a usable stunnel.pem in +your working directory. + +Next is to create a configuration file for stunnel. It will direct +stunnel what to do. You can use the following basic file: + +:: + +; Certificate/key is needed in server modecert = /etc/stunnel/stunnel.pem; Some debugging stuff useful for troubleshootingdebug = 7foreground=yes + + [ssyslog] + accept = 60514 + connect = 61514 + +Save this file to e.g. /etc/stunnel/syslog-server.conf. Please note that +the settings in *italics* are for debugging only. They run stunnel with +a lot of debug information in the foreground. This is very valuable +while you setup the system - and very useless once everything works +well. So be sure to remove these lines when going to production. + +Finally, you need to start the stunnel daemon. Under Debian, this is +done via "stunnel /etc/stunnel/syslog.server.conf". If you have enabled +the debug settings, you will immediately see a lot of nice messages. + +Now you have stunnel running, but it obviously unable to talk to rsyslog +- because it is not yet running. If not already done, configure it so +that it does everything you want. If in doubt, you can simply copy +/etc/syslog.conf to /etc/rsyslog.conf and you probably have what you +want. The really important thing in rsyslogd configuration is that you +must make it listen to tcp port 61514 (remember: this is where stunnel +send the messages to). Thankfully, this is easy to achieve: just add "-t +61514" to the rsyslogd startup options in your system startup script. +After done so, start (or restart) rsyslogd. + +The server should now be fully operational. + +Client Setup +~~~~~~~~~~~~ + +The client setup is simpler. Most importantly, you do not need a +certificate (of course, you can use one if you would like to +authenticate the client, but this is beyond the scope of this paper). So +the basic thing you need to do is create the stunnel configuration file. + + :: + + ; Some debugging stuff useful for troubleshootingdebug = 7foreground=yes + + client=yes + + [ssyslog] + accept = 127.0.0.1:61514 + connect = 192.0.2.1:60514 + +Again, the text in *italics* is for debugging purposes only. I suggest +you leave it in during your initial testing and then remove it. The most +important difference to the server configuration outlined above is the +"client=yes" directive. It is what makes this stunnel behave like a +client. The accept directive binds stunnel only to the local host, so +that it is protected from receiving messages from the network (somebody +might fake to be the local sender). The address "192.0.2.1" is the +address of the server machine. You must change it to match your +configuration. Save this file to /etc/stunnel/syslog-client.conf. + +Then, start stunnel via "stunnel4 /etc/stunnel/syslog-client.conf". Now +you should see some startup messages. If no errors appear, you have a +running client stunnel instance. + +Finally, you need to tell rsyslogd to send data to the remote host. In +stock syslogd, you do this via the "@host" forwarding directive. The +same works with rsyslog, but it supports extensions to use tcp. Add the +following line to your /etc/rsyslog.conf: + + :: + + *.* @@127.0.0.1:61514 + + + +Please note the double at-sign (@@). This is no typo. It tells rsyslog +to use tcp instead of udp delivery. In this sample, all messages are +forwarded to the remote host. Obviously, you may want to limit this via +the usual rsyslog.conf settings (if in doubt, use man rsyslog.con). + +You do not need to add any special startup settings to rsyslog on the +client. Start or restart rsyslog so that the new configuration setting +takes place. + +Done +~~~~ + +After following these steps, you should have a working secure syslog +forwarding system. To verify, you can type "logger test" or a similar +smart command on the client. It should show up in the respective server +log file. If you dig out you sniffer, you should see that the traffic on +the wire is actually protected. In the configuration use above, the two +stunnel endpoints should be quite chatty, so that you can follow the +action going on on your system. + +If you have only basic security needs, you can probably just remove the +debug settings and take the rest of the configuration to production. If +you are security-sensitive, you should have a look at the various stunnel +settings that help you further secure the system. + +Preventing Systems from talking directly to the rsyslog Server +-------------------------------------------------------------- + +It is possible that remote systems (or attackers) talk to the rsyslog +server by directly connecting to its port 61514. Currently (July of +2005), rsyslog does not offer the ability to bind to the local host, +only. This feature is planned, but as long as it is missing, rsyslog +must be protected via a firewall. This can easily be done via e.g +iptables. Just be sure not to forget it. + +Conclusion +---------- + +With minimal effort, you can set up a secure logging infrastructure +employing ssl encrypted syslog message transmission. As a side note, you +also have the benefit of reliable tcp delivery which is far less prone +to message loss than udp. diff --git a/source/history.rst b/source/history.rst new file mode 100644 index 0000000..d12b36d --- /dev/null +++ b/source/history.rst @@ -0,0 +1,146 @@ +RSyslog - History +================= + +Rsyslog is a GPL-ed, enhanced syslogd. Among others, it offers support +for reliable syslog over TCP, writing to MySQL databases and fully +configurable output formats (including great timestamps). + +Rsyslog was initiated by `Rainer Gerhards <https://rainer.gerhards.net/>`_, +`Großrinderfeld <https://www.rainer-gerhards.de/grossrinderfeld/>`_. +If you are interested to learn why Rainer initiated the project, you may want +to read his blog posting on "`why the world needs another syslogd +<https://rainer.gerhards.net/2007/08/why-doesworld-need-another-syslogd.html>`_\ ". + +Rsyslog was forked in **2004** from the `sysklogd standard +package <http://www.infodrom.org/projects/sysklogd/>`_. The goal of the +rsyslog project is to provide a feature-richer and reliable syslog +daemon while retaining drop-in replacement capabilities to stock +syslogd. By "reliable", we mean support for reliable transmission modes +like TCP or `RFC +3195 <http://www.monitorware.com/Common/en/glossary/rfc3195.php>`_ +(syslog-reliable). We do NOT imply that the sysklogd package is +unreliable. + +The name "rsyslog" stems back to the planned support for +syslog-reliable. Ironically, the initial release of rsyslog did NEITHER +support syslog-reliable NOR tcp based syslog. Instead, it contained +enhanced configurability and other enhancements (like database support). +The reason for this is that full support for RFC 3195 would require even +more changes and especially fundamental architectural changes. Also, +questions asked on the loganalysis list and at other places indicated +that RFC3195 is NOT a prime priority for users, but rather better +control over the output format. So there we were, with a rsyslogd that +covers a lot of enhancements, but not a single one of these that made +its name ;) Since version 0.9.2, receiving syslog messages via plain tcp +is finally supported, a bit later sending via TCP, too. Starting with +1.11.0, RFC 3195 is finally supported at the receiving side (a.k.a. +"listener"). Support for sending via RFC 3195 is still due. Anyhow, +rsyslog has come much closer to what it name promises. + +The database support was initially included so that our web-based syslog +interface could be used. This is another open source project which can +be found under `https://loganalyzer.adiscon.com/ <https://loganalyzer.adiscon.com/>`_. +We highly recommend having a look at it. It might not work for you if +you expect thousands of messages per second (because your database won't +be able to provide adequate performance), but in many cases it is a very +handy analysis and troubleshooting tool. In the mean time, of course, +lots of people have found many applications for writing to databases, so +the prime focus is no longer on phpLogcon. + +Rsyslogd supports an enhanced syslog.conf file format, and also works +with the standard syslog.conf. In theory, it should be possible to +simply replace the syslogd binary with the one that comes with rsyslog. +Of course, in order to use any of the new features, you must re-write +your syslog.conf. To learn how to do this, please review our commented +`sample.conf <sample.conf.php>`_ file. It outlines the enhancements over +stock syslogd. Discussion has often arisen of whether having an "old +syslogd" logfile format is good or evil. So far, this has not been +solved (but Rainer likes the idea of a new format), so we need to live +with it for the time being. It is planned to be reconsidered in the 3.x +release time frame. + +If you are interested in the `IHE <http://en.wikipedia.org/wiki/IHE>`_ +environment, you might be interested to hear that rsyslog supports +message with sizes of 32k and more. This feature has been tested, but by +default is turned off (as it has some memory footprint that we didn't +want to put on users not actually requiring it). Search the file +syslogd.c and search for "IHE" - you will find easy and precise +instructions on what you need to change (it's just one line of code!). +Please note that RFC 3195/COOKED supports 1K message sizes only. It'll +probably support longer messages in the future, but it is our belief +that using larger messages with current RFC 3195 is a violation of the +standard. + +In **February 2007**, 1.13.1 was released and served for quite a while +as a stable reference. Unfortunately, it was not later released as +stable, so the stable build became quite outdated. + +In **June 2007**, Peter Vrabec from Red Hat helped us to create RPM +files for Fedora as well as supporting IPv6. There also seemed to be +some interest from the Red Hat community. This interest and new ideas +resulted in a very busy time with many great additions. + +In **July 2007**, Andrew Pantyukhin added BSD ports files for rsyslog +and liblogging. We were strongly encouraged by this too. It looks like +rsyslog is getting more and more momentum. Let's see what comes next... + +Also in **July 2007** (and beginning of August), Rainer remodeled the +output part of rsyslog. It got a clean object model and is now prepared +for a plug-in architecture. During that time, some base ideas for the +overall new object model appeared. + +In **August 2007** community involvement grew more and more. Also, more +packages appeared. We were quite happy about that. To facilitate user +contributions, we set up a `wiki <http://wiki.rsyslog.com/>`_ on August +10th, 2007. Also in August 2007, rsyslog 1.18.2 appeared, which is +deemed to be quite close to the final 2.0.0 release. With its +appearance, the pace of changes was deliberately reduced, in order to +allow it to mature (see Rainers's `blog +post <http://rgerhards.blogspot.com/2007/07/pace-of-changes-in-rsyslog.html>`_ +on this topic, written a bit early, but covering the essence). + +In **November 2007**, rsyslog became the default syslogd in Fedora 8. +Obviously, that was something we \*really\* liked. Community involvement +also is still growing. There is one sad thing to note: ever since +summer, there is an extremely hard to find segfault bug. It happens on +very rare occasions only and never in lab. We are hunting this bug for +month now, but still could not get hold of it. Unfortunately, this also +affects the new features schedule. It makes limited sense to implement +new features if problems with existing ones are not really understood. + +**December 2007** showed the appearance of a postgres output module, +contributed by sur5r. With 1.20.0, December is also the first time since +the bug hunt that we introduce other new features. It has been decided +that we carefully will add features in order to not affect the overall +project by these rare bugs. Still, the bug hunt is top priority, but we +need to have more data to analyze. At then end of December, it looked +like the bug was found (a race condition), but further confirmation from +the field is required before declaring victory. December also brings the +initial development on **rsyslog v3**, resulting in loadable input +modules, now running on a separate thread each. + +On **January, 2nd 2008**, rsyslog 1.21.2 is re-released as rsyslog +v2.0.0 stable. This is a major milestone as far as the stable build is +concerned. v3 is not yet officially announced. Other than the stable v2 +build, v3 will not be backwards compatible (including missing +compatibility to stock sysklogd) for quite a while. Config file changes +are required and some command line options do no longer work due to the +new design. + +On January, 31st 2008 the new massively-multithreaded queue engine was +released for the first time. It was a major milestone, implementing a +feature I dreamed of for more than a year. + +End of February 2008 saw the first note about RainerScript, a way to +configure rsyslogd via a script-language like configuration format. This +effort evolved out of the need to have complex expression support, which +was also the first use case. On February, 28th rsyslog 3.12.0 was +released, the first version to contain expression support. This also +meant that rsyslog from that date on supported all syslog-ng major +features, but had a number of major features exclusive to it. With +3.12.0, I consider rsyslog fully superior to syslog-ng (except for +platform support). + +Be sure to visit Rainer's `syslog +blog <https://rainer.gerhards.net/>`_ to get some more insight into +the development and futures of rsyslog and syslog in general. diff --git a/source/how2help.rst b/source/how2help.rst new file mode 100644 index 0000000..8617ff2 --- /dev/null +++ b/source/how2help.rst @@ -0,0 +1,53 @@ +How you can Help +---------------- + +**You like rsyslog and would like to lend us a helping hand?** This page +tells you how easy it is to help a little bit. You can contribute to the +project even with a single mouse click! If you could pick a single item +from the wish list, that would be awfully helpful! + +This is our wish list: + +- let others know how great rsyslog is + + - spread word about rsyslog in forums and newsgroups + - place a link to `www.rsyslog.com <http://www.rsyslog.com>`_ from + your home page + +- let us know about rsyslog - we are eager for feedback + + - tell us what you like and what you not like - so that we can + include that into development + - tell us what you use rsyslog for - especially if you have high + traffic volume or an otherwise "uncommon" deployment. We are + looking for case studies and experience how rsyslog performs in + unusual scenarios. + - allow us to post your thoughts and experiences as a "user story" + on the web site (so far, none are there ;)) + +- if you know how to create packages (rpm, deb, ...) + + - we would very much appreciate your help with package creation. We + know that it is important to have good binary packages for a + product to spread widely. Yet, we do not have the knowledge to do + it all ourselves. `Drop Rainer a + note <mailto:rgerhards@adiscon.com>`_\ if you could help us out. + +- if you have configured a device for sending syslog data, and that + device is not in our `syslog configuration + database <https://www.adiscon.com/syslog-enabled-products/#>`_, + you might want to tell us how to configure it. +- if you are a corporate user + + - you might consider `Adiscon <http://www.adiscon.com>`_'s + commercial `MonitorWare products <http://www.monitorware.com/>`_ + for Windows, e.g. to deliver Windows Event Log data to rsyslogd + (sales of the commercial products funds the open source + development - and they also work very well). + - you might be interested in `purchasing professional support or + add-on + development <http://www.adiscon.com/Common/en/Products/techsup.php>`_ + for rsyslog + +**We appreciate your help very much.** A big thank you for anything you +might do! diff --git a/source/includes/container_dev_env.inc.rst b/source/includes/container_dev_env.inc.rst new file mode 100644 index 0000000..8b30296 --- /dev/null +++ b/source/includes/container_dev_env.inc.rst @@ -0,0 +1,14 @@ +.. note:: + + The rsyslog project maintains multiple `rsyslog docker development + environment images <https://hub.docker.com/u/rsyslog/>`_. These + images have been configured specifically for use with rsyslog and are + recommended over your own build environment. Rsyslog docker development + images are named with the ``rsyslog_dev_`` prefix, followed by the + distro name. + +.. warning:: + + If you plan to copy the binary for use outside of the container you need + to make sure to use an image of the same distro/version when building + rsyslog. diff --git a/source/includes/footer.inc.rst b/source/includes/footer.inc.rst new file mode 100644 index 0000000..be102e6 --- /dev/null +++ b/source/includes/footer.inc.rst @@ -0,0 +1,22 @@ + + +.. seealso:: + + Help with configuring/using |PRODUCT|: + + - |RsyslogOfficialMailingList|_ - best route for general questions + + - GitHub: |GitHubSourceProject|_ - detailed questions, reporting issues + that are believed to be bugs with |PRODUCT| + +.. seealso:: + + Contributing to |PRODUCT|: + + - Source project: |GitHubSourceProjectREADME|_. + - Documentation: |GitHubDocProjectREADME|_ + + +Copyright 2008-2023 `Rainer Gerhards <https://rainer.gerhards.net/>`__ +(`Großrinderfeld <https://www.rainer-gerhards.de/grossrinderfeld/>`__), +and Others. diff --git a/source/includes/substitution_definitions.inc.rst b/source/includes/substitution_definitions.inc.rst new file mode 100644 index 0000000..1ba41cd --- /dev/null +++ b/source/includes/substitution_definitions.inc.rst @@ -0,0 +1,72 @@ + +.. + This file is included by the common header file, which is itself + included by means of the rst_prolog Sphinx build confiugration + file (source/conf.py). Add substitutions here instead of directly to + the rst_prolog configuration option. + + +.. |PRODUCT| replace:: ``Rsyslog`` + +.. |FmtBasicName| replace:: ``basic`` +.. |FmtAdvancedName| replace:: ``advanced`` +.. |FmtObsoleteName| replace:: ``obsolete legacy`` + +.. |FmtObsoleteDescription| replace:: ``Obsolete Format Equivalents`` + +.. |RsyslogDockerHub| replace:: official rsyslog Docker Hub +.. _RsyslogDockerHub: https://hub.docker.com/u/rsyslog/ + +.. |GitHubDockerProject| replace:: rsyslog-docker project +.. _GitHubDockerProject: https://github.com/rsyslog/rsyslog-docker + +.. |DockerApplianceAlpineDockerHubRepo| replace:: Alpine rsyslog appliance Docker Hub repo +.. _DockerApplianceAlpineDockerHubRepo: https://hub.docker.com/r/rsyslog/syslog_appliance_alpine/ + +.. |DockerApplianceAlpineName| replace:: ``rsyslog/syslog_appliance_alpine`` +.. |DockerApplianceAlpineRUN| replace:: ``docker run -ti rsyslog/syslog_appliance_alpine`` + + +.. |RsyslogPackageDownloads| replace:: rsyslog package downloads +.. _RsyslogPackageDownloads: http://www.rsyslog.com/downloads/download-other/ + +.. |GitHubDocProject| replace:: rsyslog-doc project +.. _GitHubDocProject: https://github.com/rsyslog/rsyslog-doc/ + +.. |GitHubDocProjectREADME| replace:: rsyslog-doc project README +.. _GitHubDocProjectREADME: https://github.com/rsyslog/rsyslog-doc/blob/master/README.md + +.. |GitHubDocProjectDevREADME| replace:: rsyslog-doc project BUILDS README +.. _GitHubDocProjectDevREADME: https://github.com/rsyslog/rsyslog-doc/blob/master/BUILDS_README.md + +.. |GitHubDocProjectGoodFirstIssueLabel| replace:: rsyslog-doc issues marked with Good First Issue label +.. _GitHubDocProjectGoodFirstIssueLabel: https://github.com/rsyslog/rsyslog-doc/labels/good%20first%20issue + + +.. |GitHubDocProjectHelpWantedLabel| replace:: rsyslog-doc issues marked with Help Wanted label +.. _GitHubDocProjectHelpWantedLabel: https://github.com/rsyslog/rsyslog-doc/labels/help%20wanted + +.. |RsyslogOfficialForums| replace:: Forum +.. _RsyslogOfficialForums: http://kb.monitorware.com/rsyslog-f40.html + +.. |RsyslogStackExchangeAsk| replace:: Ask +.. _RsyslogStackExchangeAsk: https://serverfault.com/questions/ask?tags=rsyslog + +.. |RsyslogStackExchangeView| replace:: View +.. _RsyslogStackExchangeView: https://stackexchange.com/filters/327462/rsyslog + +.. |RsyslogOfficialMailingList| replace:: Mailing list +.. _RsyslogOfficialMailingList: http://lists.adiscon.net/mailman/listinfo/rsyslog + + +.. |GitHubSourceProject| replace:: rsyslog source project +.. _GitHubSourceProject: https://github.com/rsyslog/rsyslog/ + +.. |GitHubSourceProjectREADME| replace:: rsyslog project README +.. _GitHubSourceProjectREADME: https://github.com/rsyslog/rsyslog/blob/master/README.md + +.. |GitHubSourceProjectGoodFirstIssueLabel| replace:: rsyslog issues marked with Good First Issue label +.. _GitHubSourceProjectGoodFirstIssueLabel: https://github.com/rsyslog/rsyslog/labels/good%20first%20issue + +.. |GitHubSourceProjectHelpWantedLabel| replace:: rsyslog issues marked with Help Wanted label +.. _GitHubSourceProjectHelpWantedLabel: https://github.com/rsyslog/rsyslog/labels/help%20wanted diff --git a/source/index.rst b/source/index.rst new file mode 100644 index 0000000..5c20540 --- /dev/null +++ b/source/index.rst @@ -0,0 +1,78 @@ +Welcome to Rsyslog +================== + +`Rsyslog <http://www.rsyslog.com/>`_ is a **r**\ ocket-fast **sys**\ tem for **log** processing. +It offers high-performance, great security features and a modular design. +While it started as a regular syslogd, rsyslog has evolved into a kind of +**swiss army knife of logging**, being able to + +- accept inputs from a wide variety of sources, +- transform them, +- and output the results to diverse destinations. + +Rsyslog has a strong enterprise focus but also scales down to small +systems. +It supports, among others, :doc:`MySQL <tutorials/database>`, +:doc:`PostgreSQL <tutorials/database>`, +:doc:`failover log destinations <tutorials/failover_syslog_server>`, +ElasticSearch, syslog/tcp transport, fine grain output format control, +high precision timestamps, +queued operations and the ability to filter on any message part. + +Manual +------ +.. toctree:: + :maxdepth: 2 + + installation/index + configuration/index + containers/index + troubleshooting/index + faq/index + concepts/index + examples/index + tutorials/index + development/index + historical/index + +Reference +--------- +.. toctree:: + :maxdepth: 1 + + history + licensing + how2help + community + features + proposals/index + whitepapers/index + free_support + compatibility/index + +Sponsors and Community +---------------------- + +Please visit the rsyslog `Sponsor's Page`_ to honor the project sponsors or +become one yourself! We are very grateful for any help towards the project +goals. + +If you like rsyslog, you might want to lend us a helping hand. It +doesn't require a lot of time - even a single mouse click helps. Learn +:doc:`how2help`. + +.. _Sponsor's Page: http://www.rsyslog.com/sponsors + +Contributing to the docs +------------------------ + +This documentation is hosted on `github +<https://github.com/rsyslog/rsyslog-doc>`_. If you find something to be +improved, please feel free to fork and file a patch request with your +improvements. There is also a Button 'Edit in GitHub' on every documentation +page beginning with the main `docs page +<https://www.rsyslog.com/doc/v8-stable/>`_ that allows easy access. + +.. only:: dev + + Built on |today| from branch |DOC_BRANCH|, commit |DOC_COMMIT|. diff --git a/source/installation/.install_from_source.rst.swp b/source/installation/.install_from_source.rst.swp Binary files differnew file mode 100644 index 0000000..df6ea0c --- /dev/null +++ b/source/installation/.install_from_source.rst.swp diff --git a/source/installation/build_from_repo.rst b/source/installation/build_from_repo.rst new file mode 100644 index 0000000..d948626 --- /dev/null +++ b/source/installation/build_from_repo.rst @@ -0,0 +1,73 @@ +Installing rsyslog from the source repository +============================================= + +In most cases, people install rsyslog either via a package or use an +"official" distribution tarball to generate it. But there may be +situations where it is desirable to build directly from the source +repository. This is useful for people who would like to participate in +development or who would like to use the latest, not-yet-released code. +The later may especially be the case if you are asked to try out an +experimental version. + +Building from the repository is not much different than building from the +source tarball, but some files are missing because they are output files +and thus do not belong into the repository. + +Obtaining the Source +-------------------- + +First of all, you need to download the sources. Rsyslog is kept in git. +The "`Where to find the rsyslog source +code <http://www.rsyslog.com/where-to-find-the-rsyslog-source-code/>`_\ " +page on the project site will point you to the current repository +location. + +After you have cloned the repository, you are in the master branch by +default. This is where we keep the devel branch. If you need any other +branch, you need to do a "git checkout --track -b branch origin/branch". +For example, the command to check out the beta branch is "git checkout +--track -b beta origin/beta". + +Prequisites +----------- + +.. include:: /includes/container_dev_env.inc.rst + +To build the compilation system, you need + +* GNU autotools (autoconf, automake, ...) +* libtool +* pkg-config + +Unfortunately, the actual package names vary between distributions. Doing +a search for the names above inside the packaging system should lead to +the right path, though. + +If some of these tools are missing, you will see errors like this one: + +:: + + checking for SYSLOG_UNIXAF support... yes + checking for FSSTND support... yes + ./configure: line 25895: syntax error near unexpected token `RELP,' + ./configure: line 25895: ` PKG_CHECK_MODULES(RELP, relp >= 0.1.1)' + +The actual error message will vary. In the case shown here, pkg-config +was missing. + +**Important:** the build dependencies must be present **before** creating +the build environment is begun. Otherwise, some hard to interpret errors may +occur. For example, the error above will also occur if you install +pkg-config, but *after* you have run *autoreconf*. So be sure everything +is in place *before* you create the build environment. + +Creating the Build Environment +------------------------------ + +This is fairly easy: just issue "**autoreconf -fvi**\ ", which should do +everything you need. Once this is done, you can follow the usual +./configure steps just like when you downloaded an official distribution +tarball (see the `rsyslog install guide <install.html>`_, starting at +step 2, for further details about that). + + diff --git a/source/installation/index.rst b/source/installation/index.rst new file mode 100644 index 0000000..8cd4d64 --- /dev/null +++ b/source/installation/index.rst @@ -0,0 +1,26 @@ +Installation +============ + +Installation is usually as simple as typing + +| ``$ sudo yum install rsyslog``, +| ``$ sudo apt-get install rsyslog``, or +| ``$ sudo apk add rsyslog`` + +Unfortunately distributions usually provide rather old versions of +rsyslog, and so there are chances you want to have something +newer. To do this easily, we provide :doc:`packages <packages>` +and :doc:`Docker containers <rsyslog_docker>`. + +Alternatively you can build directly from source. That provides most +flexibility and control over the resulting binaries, but obviously also +requires most work. Some prior knowledge with building software on +your system is recommended. + +.. toctree:: + :maxdepth: 2 + + packages + rsyslog_docker + install_from_source + build_from_repo diff --git a/source/installation/install_from_source.rst b/source/installation/install_from_source.rst new file mode 100644 index 0000000..282e3b2 --- /dev/null +++ b/source/installation/install_from_source.rst @@ -0,0 +1,238 @@ +Installing rsyslog from Source +============================== + +*Written by* `Rainer Gerhards <https://rainer.gerhards.net>`_ + +**In this paper, I describe how to install** +`rsyslog <http://www.rsyslog.com/>`_. It is intentionally a brief +step-by-step guide, targeted to those who want to quickly get it up and +running. For more elaborate information, please consult the rest of the +:doc:`manual set <../index>`. + +How to make your life easier... +------------------------------- + +In addition to building from source, you can also install |PRODUCT| +using packages. If you use them, you can spare yourself many of the steps +below. This is highly recommended if there is a package for your +distribution available. See :doc:`packages` for instructions. + +Steps To Do +----------- + +Step 1 - Download Software +~~~~~~~~~~~~~~~~~~~~~~~~~~ + +For obvious reasons, you need to download rsyslog. Here, I assume that +you use a distribution tarball. If you would like to use a version +directly from the repository, see :doc:`build_from_repo` instead. + +Load the most recent build from +`http://www.rsyslog.com/downloads <http://www.rsyslog.com/downloads>`_. +Extract the software with "tar xzf -nameOfDownloadSet-". This will +create a new subdirectory rsyslog-version in the current working +directory. cd into that. + +Depending on your system configuration, you also need to install some +build tools, most importantly make, the gcc compiler and the MySQL +development system (if you intend to use MySQL - the package is often +named "mysql-dev"). On many systems, these things should already be +present. If you don't know exactly, simply skip this step for now and +see if nice error messages pop up during the compile process. If they +do, you can still install the missing build environment tools. So this +is nothing that you need to look at very carefully. + + +Build Requirements +~~~~~~~~~~~~~~~~~~ + +.. include:: /includes/container_dev_env.inc.rst + +At a minimum, the following development tools must be present on the +system: + +* C compiler (usually gcc) +* make +* libtool +* rst2man (part of Python docutils) if you want to generate the man files +* Bison and Flex (preferably, otherwise yacc and lex) +* zlib development package (usually *libz-dev*) +* json-c (usually named *libjson0-dev* or similar) +* libuuid (usually *uuid-dev*, if not present use --disable-uuid) +* libgcrypt (usually *libgcrypt-dev*) + +Also, development versions of the following supporting libraries +that the rsyslog project provides are necessary: + +* liblogging (only stdlog component is hard requirement) +* libfastjson +* libestr + +In contrast to the other dependencies, recent versions of rsyslog may +require recent versions of these libraries as well, so there is a chance +that they must be built from source, too. + +Depending on which plugins are enabled, additional dependencies exist. +These are reported during the ./configure run. + +**Important**: you need the **development** version of the packages in +question. That is the version which is used by developers to build software +that uses the respective package. Usually, they are separate from the +regular user package. So if you just install the regular package but not +the development one, ./configure will fail. + +As a concrete example, you may want to build ommysql. It obviously requires +a package like *mysql-client*, but that is just the regular package and not +sufficient to build rsyslog successfully. To do so, you need to also install +something named like *mysql-client-dev*. + +Usually, the regular package is +automatically installed, when you select the development package, but not +vice versa. The exact behaviour and names depend on the distribution you use. +It is quite common to name development packages something along the line of +*pkgname-dev* or *pkgname-devel* where *pkgname* is the regular package name +(like *mysql-client* in the above example). + + +Step 2 - Run ./configure +~~~~~~~~~~~~~~~~~~~~~~~~ + +Run ./configure to adopt rsyslog to your environment. While doing so, +you can also enable options. Configure will display selected options +when it is finished. For example, to enable MySQL support, run:: + + ./configure --enable-mysql + +Please note that MySQL support by default is NOT disabled. + +To learn which ./configure options are available and what their +default values are, use + +``./configure --help`` + + +Step 3 - Compile +~~~~~~~~~~~~~~~~ + +That is easy. Just type "make" and let the compiler work. On any recent +system, that should be a very quick task, on many systems just a matter +of a few seconds. If an error message comes up, most probably a part of +your build environment is not installed. Check with step 1 in those +cases. + +Step 4 - Install +~~~~~~~~~~~~~~~~ + +Again, that is quite easy. All it takes is a "sudo make install". That will +copy the rsyslogd and the man pages to the relevant directories. + +Step 5 - Configure rsyslogd +~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +In this step, you tell rsyslogd what to do with received messages. If +you are upgrading from stock syslogd, /etc/syslog.conf is probably a +good starting point. Rsyslogd understands stock syslogd syntax, so you +can simply copy over /etc/syslog.conf to /etc/rsyslog.conf. Note since +version 3 rsyslog requires to load plug-in modules to perform useful +work. + +.. seealso:: + + :doc:`/compatibility/v3compatibility` + +To load the most common plug-ins, add the following to the top of +rsyslog.conf: + +:: + + $ModLoad immark # provides --MARK-- message capability + $ModLoad imudp # provides UDP syslog reception + $ModLoad imtcp # provides TCP syslog reception + $ModLoad imuxsock # provides support for local system logging + $ModLoad imklog # provides kernel logging support + +Change rsyslog.conf for any further enhancements you would like to see. +For example, you can add database writing as outlined in the paper +:doc:`/tutorials/database` (remember you need to enable MySQL +support during step 2 if you want to do that!). + +Step 6 - Disable stock syslogd +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +**You can skip this and the following steps if rsyslog was already +installed as the stock +syslogd on your system (e.g. via a distribution default or package).** +In this case, you are finished. + +If another syslogd is installed, it must be disabled and rsyslog set +to become the default. This is because +both it and rsyslogd listen to the same sockets, they can NOT be run +concurrently. So you need to disable the stock syslogd. To do this, you +typically must change your rc.d startup scripts. + +For example, under `Debian <http://www.debian.org/>`_ this must be done +as follows: The default runlevel is 2. We modify the init scripts for +runlevel 2 - in practice, you need to do this for all run levels you +will ever use (which probably means all). Under /etc/rc2.d there is a +S10sysklogd script (actually a symlink). Change the name to +\_S10sysklogd (this keeps the symlink in place, but will prevent further +execution - effectively disabling it). + +Step 7 - Enable rsyslogd Autostart +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +This step is very close to step 3. Now, we want to enable rsyslogd to +start automatically. The rsyslog package contains a (currently small) +number of startup scripts. They are inside the distro-specific directory +(e.g. debian). If there is nothing for your operating system, you can +simply copy the stock syslogd startup script and make the minor +modifications to run rsyslogd (the samples should be of help if you +intend to do this). + +In our Debian example, the actual scripts are stored in /etc/init.d. +Copy the standard script to that location. Then, you need to add a +symlink to it in the respective rc.d directory. In our sample, we modify +rc2.d, and can do this via the command "ln -s ../init.d/rsyslogd +S10rsyslogd". Please note that the S10 prefix tells the system to start +rsyslogd at the same time stock sysklogd was started. + +**Important:** if you use the database functionality, you should make +sure that MySQL starts before rsyslogd. If it starts later, you will +receive an error message during each restart (this might be acceptable +to you). To do so, either move MySQL's start order before rsyslogd or +rsyslogd's after MySQL. + +Step 8 - Check daily cron scripts +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +Most distributions come pre-configured with some daily scripts for log +rotation. As long as you use the same log file names, the log rotation +scripts will probably work quite well. There is one caveat, though. The +scripts need to tell syslogd that the files have been rotated. To do +this, they typically have a part using syslogd's init script to do that. +Obviously, scripts for other default daemons do not know about rsyslogd, so they +manipulate the other one. If that happens, in most cases an additional +instance of that daemon is started. It also means that rsyslogd +is not properly told about the log rotation, which will lead it to +continue to write to the now-rotated files. + +So you need to fix these scripts. See your distro-specific documentation +how they are located. + +Done +~~~~ + +This concludes the steps necessary to install rsyslog. Of course, it is +always a good idea to test everything thoroughly. At a minimalist level, +you should do a reboot and after that check if everything has come up +correctly. Pay attention not only to running processes, but also check +if the log files (or the database) are correctly being populated. + +If rsyslogd encounters any serious errors during startup, you should be +able to see them at least on the system console. They might not be in +log file, as errors might occur before the log file rules are in place. +So it is always a good idea to check system console output when things +don't go smooth. In some rare cases, enabling debug logging (-d option) +in rsyslogd can be helpful. If all fails, go to +`www.rsyslog.com <http://www.rsyslog.com>`_ and check the forum or +mailing list for help with your issue. diff --git a/source/installation/packages.rst b/source/installation/packages.rst new file mode 100644 index 0000000..2373f2a --- /dev/null +++ b/source/installation/packages.rst @@ -0,0 +1,65 @@ +Installing rsyslog from Package +=============================== +Installing from package is usually the most convenient way to install +rsyslog. Usually, the regular package manager can be used. + +Package Availability +-------------------- + +**Rsyslog is included in all major distributions.** So you do not +necessarily need to take care of where packages can be found - they +are "just there". Unfortunately, the distros provide often rather old +versions. This is especially the case for so-called enterprise +distributions. + +As long as you do not run into trouble with one of these old versions, using +the distribution-provided packages is easy and a good idea. If you need +new features, better performance and sometimes even a fix for a bug that +the distro did not backport, you can use alternative packages. Please note +that the project team does not support outdated versions. While we probably +can help with simple config questions, for anything else we concentrate on +current versions. + +The rsyslog project offers current packages for a number of major distributions. +More information about these can be found at the |RsyslogPackageDownloads|_ +page. + +If you do not find a suitable package for your distribution, there is no +reason to panic. You can use official rsyslog docker containers or +install rsyslog from the source tarball. + +.. seealso:: + + - :doc:`rsyslog_docker` + - :doc:`install_from_source` + +Package Structure +----------------- +Almost all distributions package rsyslog in multiple packages. This is also +the way Adiscon packages are created. The reason is that rsyslog has so many +input and output plugins that enable it to connect to different systems +like MariaDB/mysql, Kafka, ElasticSearch and so on. If everything were provided in a +single gigantic package, you would need to install all of these dependencies, +even though they are mostly not needed. + +For that reason, rsyslog comes with multiple packages: + +* *core package* (usually just called "rsyslog") - this contains core + technology that is required as a base for all other packages. It also + contains modules like the file writer or syslog forwarder that is extremely + often used and has little dependencies. +* *feature package* (usually called "rsyslog-feature") - there are + multiple of these packages. What exactly is available and how it is + named depends on the distro. This unfortunately is a bit inconsistent. + Usually, it is a good guess that the package is intuitively named, + e.g. "rsyslog-mysql" for the MySQL component and "rsyslog-elasticsearch" + for ElasticSearch support. If in doubt, it is suggested to use the + distro's package manager and search for "rsyslog*". + +Contributing +------------ +**Packaging is a community effort.** If you would like to see support for an +additional distribution and know how to build packages, please consider +contributing to the project and joining the packaging team. Also, rsyslog's +presence on github also contains the sources for the currently +maintained packages. They can be found at the |GitHubSourceProject|_. diff --git a/source/installation/rsyslog_docker.rst b/source/installation/rsyslog_docker.rst new file mode 100644 index 0000000..d80987e --- /dev/null +++ b/source/installation/rsyslog_docker.rst @@ -0,0 +1,23 @@ +Using Rsyslog Docker Containers +=============================== + +The rsyslog project provides a ready-to-run "syslog appliance" which provides +all rsyslog features in an easy to use way. To run it, simply do + +|DockerApplianceAlpineRun| + +Up-to-date information on how to use this container can be found at the +|DockerApplianceAlpineDockerHubRepo|_. + +.. warning:: + + The docker containers are currently (early 2018) under development + and must be used with some care. + +Further Information +------------------- +The rsyslog project also provides a number of additional containers for +different needs (end users, developers, package builders, ...). A full +overview of what is currently available can be found at the |RsyslogDockerHub|_. +Source code for the docker containers is kept in Github at +|GitHubDockerProject|_. diff --git a/source/licensing.rst b/source/licensing.rst new file mode 100644 index 0000000..933f221 --- /dev/null +++ b/source/licensing.rst @@ -0,0 +1,72 @@ +Licensing +========= + +If you intend to use rsyslog inside a GPLv3 compatible project, you are free to +do so. You don't even need to continue reading. If you intend to use rsyslog +inside a non-GPLv3 compatible project, rsyslog offers you some liberties to do +that, too. However, you then need to study the licensing details in depth. + +The project hopes this is a good compromise, which also gives a boost to +fellow free software developers who release under GPLv3. + +And now on to the dirty and boring license details, still on a executive +summary level. For the real details, check source files and the files +COPYING and COPYING.LESSER inside the distribution. + +The rsyslog package contains several components: + +- the rsyslog core programs (like rsyslogd) +- plugins (like imklog, omrelp, ...) +- the rsyslog runtime library + +Each of these components can be thought of as individual projects. In +fact, some of the plugins have different main authors than the rest of +the rsyslog package. All of these components are currently put together +into a single "rsyslog" package (tarball) for convenience: this makes it +easier to distribute a consistent version where everything is included +(and in the right versions) to build a full system. Platform package +maintainers in general take the overall package and split off the +individual components, so that users can install only what they need. In +source installations, this can be done via the proper ./configure +switches. + +However, while it is convenient to package all parts in a single +tarball, it does not imply all of them are necessarily covered by the +same license. Traditionally, GPL licenses are used for rsyslog, because +the project would like to provide free software. GPLv3 has been used +since around 2008 to help fight for our freedom. All rsyslog core +programs are released under GPLv3. But, from the beginning on, plugins +were separate projects and we did not impose and license restrictions on +them. So even though all plugins that currently ship with the rsyslog +package are also placed under GPLv3, this can not taken for granted. You +need to check each plugins license terms if in question - this is +especially important for plugins that do NOT ship as part of the rsyslog +tarball. + +In order to make rsyslog technology available to a broader range of +applications, the rsyslog runtime is, at least partly, licensed under +LGPL. If in doubt, check the source file licensing comments. As of now, +the following files are licensed under LGPL: + +- queue.c/.h +- wti.c/.h +- wtp.c/.h +- vm.c/.h +- vmop.c/.h +- vmprg.c/.h +- vmstk.c/.h +- expr.c/.h +- sysvar.c/.h +- ctok.c/.h +- ctok\_token.c/.h +- regexp.c/.h +- sync.c/.h +- stream.c/.h +- var.c/.h + +This list will change as time of the runtime modularization. At some +point in the future, there will be a well-designed set of files inside a +runtime library branch and all of these will be LGPL. Some select extras +will probably still be covered by GPL. We are following a similar +licensing model in GnuTLS, which makes effort to reserve some +functionality exclusively to open source projects. diff --git a/source/module_workflow.png b/source/module_workflow.png Binary files differnew file mode 100644 index 0000000..e1a72e9 --- /dev/null +++ b/source/module_workflow.png diff --git a/source/proposals/big_restructuring/book/extending.rst b/source/proposals/big_restructuring/book/extending.rst new file mode 100644 index 0000000..0797206 --- /dev/null +++ b/source/proposals/big_restructuring/book/extending.rst @@ -0,0 +1,9 @@ +Extending rsyslog +================= + +Native plugins +-------------- + +External plugins +---------------- + diff --git a/source/proposals/big_restructuring/book/first_setup.rst b/source/proposals/big_restructuring/book/first_setup.rst new file mode 100644 index 0000000..9102c66 --- /dev/null +++ b/source/proposals/big_restructuring/book/first_setup.rst @@ -0,0 +1,6 @@ +Create your first Rsyslog setup +=============================== + +Teach how to get log messages from `logger` command and write to files conditionally. + + diff --git a/source/proposals/big_restructuring/book/index.rst b/source/proposals/big_restructuring/book/index.rst new file mode 100644 index 0000000..5b5260f --- /dev/null +++ b/source/proposals/big_restructuring/book/index.rst @@ -0,0 +1,14 @@ +The Book +======== + +.. toctree:: + + overview + installing + first_setup + language + input + output + queues + security + extending diff --git a/source/proposals/big_restructuring/book/input.rst b/source/proposals/big_restructuring/book/input.rst new file mode 100644 index 0000000..3938971 --- /dev/null +++ b/source/proposals/big_restructuring/book/input.rst @@ -0,0 +1,3 @@ +Input: from where come the logs +=============================== + diff --git a/source/proposals/big_restructuring/book/installing.rst b/source/proposals/big_restructuring/book/installing.rst new file mode 100644 index 0000000..9f1c6e8 --- /dev/null +++ b/source/proposals/big_restructuring/book/installing.rst @@ -0,0 +1,148 @@ +Installing and configuring Rsyslog +================================== + +General procedures to install and configure. + + +Installing from packages +------------------------ + +How to install using apt-get, yum, etc. + + +Installing from sources +----------------------- + +How to compile the sources into your system. + +Testing configuration blocks + + + .. code-block:: bash + + #### MODULES #### + + # Load (i)nput and (o)utput (m)odules + module(load="imuxsock") + module(load="imklog") + module(load="imudp") + module(load="imtcp") + module(load="imrelp") + module(load="omrelp") + module(load="impstats" interval="3600" severity="7" log.syslog="off" log.file="/var/log/rsyslog-stats.log") + + # Module parameters + input(type="imrelp" port="1514" ruleset="remote") + input(type="imtcp" port="514" ruleset="remote") + input(type="imudp" port="514" ruleset="remote") + + #### GLOBAL DIRECTIVES #### + + # Use default timestamp format + $ActionFileDefaultTemplate RSYSLOG_TraditionalFileFormat + + # Spool files + $WorkDirectory /var/spool/rsyslog + + # Filter duplicate messages + $RepeatedMsgReduction on + + #### RULES #### + + #...cut out standard log rules for brevity...# + + ruleset(name="remote"){ + + action(Name="storage" + Type="omrelp" + Target="10.1.1.100" + Port="514" + Action.ExecOnlyWhenPreviousIsSuspended="on" + queue.FileName="storage-buffer" + queue.SaveOnShutdown="on" + queue.Type="LinkedList" + Action.ResumeInterval="30" + Action.ResumeRetryCount="-1" + Timeout="5") + + action(Name="analysis" + Type="omrelp" + Target="10.1.1.101" + Port="514" + Action.ExecOnlyWhenPreviousIsSuspended="on" + queue.FileName="analysis-buffer" + queue.SaveOnShutdown="on" + queue.Type="LinkedList" + Action.ResumeInterval="30" + Action.ResumeRetryCount="-1" + Timeout="5") + + action(Name="indexer" + Type="omfwd" + Target="10.1.1.102" + Protocol="tcp" + Port="514" + Action.ExecOnlyWhenPreviousIsSuspended="on" + queue.FileName="indexer-buffer" + queue.SaveOnShutdown="on" + queue.Type="LinkedList" + Action.ResumeInterval="30" + Action.ResumeRetryCount="-1" + Timeout="5") + } + + #### INCLUDES #### + + # Includes config files (Do these last) + $IncludeConfig /etc/rsyslog.d/*.conf + + +.. note:: + + You'll learn exactly how to load each file/format in the next section. + +.. option:: dest_dir + + Destination directory. + +.. option:: -m <module>, --module <module> + + Run a module as a script. + +.. envvar:: nome_envvar + +Descrevendo um programa. + +.. program:: rm + +.. option:: -r + + Work recursively. + +.. program:: svn + +.. option:: -r revision + + Specify the revision to work upon. + +------------------------------------------------- + +.. describe:: PAPER + + You can set this variable to select a paper size. + +------------------------------------------------- + + todo:: + + Este item é do TO DO. + +------------------------------------------------- + + todolist:: + + none + +------------------------------------------------- + +FIM diff --git a/source/proposals/big_restructuring/book/language.rst b/source/proposals/big_restructuring/book/language.rst new file mode 100644 index 0000000..c75a42f --- /dev/null +++ b/source/proposals/big_restructuring/book/language.rst @@ -0,0 +1,29 @@ +Configuration format +==================== + +Currently there are two ways of creating your configuration +script: RainerScript and the legacy format. + + +RainerScript format +------------------- + +General guidelines. + + +Legacy configuration format (deprecated) +---------------------------------------- + +General guidelines. + + +Why is there two different formats? +----------------------------------- + +Explain! + + + todo:: + + Este item é do TO DO in language-rst. + diff --git a/source/proposals/big_restructuring/book/output.rst b/source/proposals/big_restructuring/book/output.rst new file mode 100644 index 0000000..45fcc50 --- /dev/null +++ b/source/proposals/big_restructuring/book/output.rst @@ -0,0 +1,63 @@ +Output +====== + +What should be logged +--------------------- + +Message properties +^^^^^^^^^^^^^^^^^^ + + +System properties +^^^^^^^^^^^^^^^^^ + + +Variables +^^^^^^^^^ + + +Functions +^^^^^^^^^ + + +Transformation Modules +^^^^^^^^^^^^^^^^^^^^^^ + + +When should be logged +--------------------- + +Filter Conditions +^^^^^^^^^^^^^^^^^ + + * “traditional” severity and facility based selectors + * property-based filters + * expression-based filters + * BSD-style blocks (not upward compatible) + +Rulesets +^^^^^^^^ + + +How should be logged +-------------------- + + +RainerScript templates +^^^^^^^^^^^^^^^^^^^^^^ + + +Legacy format templates +^^^^^^^^^^^^^^^^^^^^^^^ + + +Properties in templates +^^^^^^^^^^^^^^^^^^^^^^^ + + +Conditionally choosing a template +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + + +Where should be send: Output Modules +------------------------------------ diff --git a/source/proposals/big_restructuring/book/overview.rst b/source/proposals/big_restructuring/book/overview.rst new file mode 100644 index 0000000..44c47d8 --- /dev/null +++ b/source/proposals/big_restructuring/book/overview.rst @@ -0,0 +1,38 @@ +Overview +======== + +Write a bit about the logging challenge. + +What is Rsyslog? +---------------- + +`Rsyslog <http://www.rsyslog.com/>`_ is a **r**\ ocket-fast **sys**\ tem for **log** processing. +It offers high-performance, great security features and a modular design. +While it started as a regular syslogd, rsyslog has evolved into a kind of +**swiss army knife of logging**, being able to + +- accept inputs from a wide variety of sources, +- transform them, +- and output the results to diverse destinations. + +Rsyslog has a strong enterprise focus but also scales down to small +systems. + +Message flow in rsyslog +----------------------- + +From where to where and when... describes the flow. + +Input +^^^^^ + +Message Transformation +^^^^^^^^^^^^^^^^^^^^^^ + +Output +^^^^^^ + +Output format: Templates +"""""""""""""""""""""""" + + diff --git a/source/proposals/big_restructuring/book/queues.rst b/source/proposals/big_restructuring/book/queues.rst new file mode 100644 index 0000000..cb35d74 --- /dev/null +++ b/source/proposals/big_restructuring/book/queues.rst @@ -0,0 +1,23 @@ +Queues: prepare for the worst +============================= + + +What are queues? +---------------- + +In-memory queues +^^^^^^^^^^^^^^^^ + +Disk queues +^^^^^^^^^^^ + +Disk-assisted queues +^^^^^^^^^^^^^^^^^^^^ + + +Main message queue +------------------ + +Action queues +------------- + diff --git a/source/proposals/big_restructuring/book/security.rst b/source/proposals/big_restructuring/book/security.rst new file mode 100644 index 0000000..573086e --- /dev/null +++ b/source/proposals/big_restructuring/book/security.rst @@ -0,0 +1,9 @@ +Security +======== + +Securing your setup +------------------- + +Dropping privileges +------------------- + diff --git a/source/proposals/big_restructuring/contributing/code/git.rst b/source/proposals/big_restructuring/contributing/code/git.rst new file mode 100644 index 0000000..e2a7176 --- /dev/null +++ b/source/proposals/big_restructuring/contributing/code/git.rst @@ -0,0 +1,41 @@ +Git +=== + +This document explains some conventions and specificities in the way we manage +the Rsyslog code with Git. + +Pull Requests +------------- + +Whenever a pull request is merged, all the information contained in the pull +request (including comments) is saved in the repository. + +You can easily spot pull request merges as the commit message always follows +this pattern: + +.. code-block:: text + + merged branch USER_NAME/BRANCH_NAME (PR #1111) + +The PR reference allows you to have a look at the original pull request on +GitHub: https://github.com/rsyslog/rsyslog/pull/1111. But all the information +you can get on GitHub is also available from the repository itself. + +The merge commit message contains the original message from the author of the +changes. Often, this can help understand what the changes were about and the +reasoning behind the changes. + +Moreover, the full discussion that might have occurred back then is also +stored as a Git note. To get access to these notes, add this line to +your ``.git/config`` file: + +.. code-block:: ini + + fetch = +refs/notes/*:refs/notes/* + +After a fetch, getting the GitHub discussion for a commit is then a matter of +adding ``--show-notes=github-comments`` to the ``git show`` command: + +.. code-block:: bash + + $ git show HEAD --show-notes=github-comments diff --git a/source/proposals/big_restructuring/contributing/code/index.rst b/source/proposals/big_restructuring/contributing/code/index.rst new file mode 100644 index 0000000..734fa33 --- /dev/null +++ b/source/proposals/big_restructuring/contributing/code/index.rst @@ -0,0 +1,8 @@ +Contributing Code +================= + +.. toctree:: + :maxdepth: 2 + + standards + git diff --git a/source/proposals/big_restructuring/contributing/code/standards.rst b/source/proposals/big_restructuring/contributing/code/standards.rst new file mode 100644 index 0000000..5528af0 --- /dev/null +++ b/source/proposals/big_restructuring/contributing/code/standards.rst @@ -0,0 +1,10 @@ +Coding Standards +================ + +When contributing code to Rsyslog, you must follow its coding standards. To +make a long story short, here is the golden rule: **Imitate the existing +Rsyslog code**. Most open-source modules and libraries recommended by Rsyslog also +follow the same guidelines, and you should too. + +Remember that the main advantage of standards is that every piece of code +looks and feels familiar, it's not about this or that being more readable. diff --git a/source/proposals/big_restructuring/contributing/community/index.rst b/source/proposals/big_restructuring/contributing/community/index.rst new file mode 100644 index 0000000..43b7b52 --- /dev/null +++ b/source/proposals/big_restructuring/contributing/community/index.rst @@ -0,0 +1,8 @@ +Community +========= + +.. toctree:: + :maxdepth: 2 + + releases + other diff --git a/source/proposals/big_restructuring/contributing/community/other.rst b/source/proposals/big_restructuring/contributing/community/other.rst new file mode 100644 index 0000000..26b2cce --- /dev/null +++ b/source/proposals/big_restructuring/contributing/community/other.rst @@ -0,0 +1,13 @@ +Other Resources +=============== + +In order to follow what is happening in the community you might find helpful +these additional resources: + +* List of open pull requests `pull requests`_ +* List of recent `commits`_ +* List of open bugs and enhancements `bugs and enhancements`_ + +.. _pull requests: https://github.com/rsyslog/rsyslog/pulls +.. _commits: https://github.com/rsyslog/rsyslog/commits/master +.. _bugs and enhancements: https://github.com/rsyslog/rsyslog/issues diff --git a/source/proposals/big_restructuring/contributing/community/releases.rst b/source/proposals/big_restructuring/contributing/community/releases.rst new file mode 100644 index 0000000..2486eda --- /dev/null +++ b/source/proposals/big_restructuring/contributing/community/releases.rst @@ -0,0 +1,43 @@ +The Release Process +=================== + +This document explains the Rsyslog release process (Rsyslog being the code +hosted on the main ``rsyslog/rsyslog`` `Git repository`_). + +Rsyslog manages its releases through a *time-based model*; a new Rsyslog minor +version comes out every *six weeks*. + +.. tip:: + + The meaning of "minor" comes from the `Semantic Versioning`_ strategy. + +Each minor version sticks to the same very well-defined process where we start +with a development period, followed by a maintenance period. + +.. note:: + + This release process has been adopted as of Rsyslog 8.2, and all the + "rules" explained in this document must be strictly followed as of Rsyslog + 8.3. + +.. _contributing-release-development: + +Development +----------- + +The full development period lasts six weeks and is divided into two phases: + +* *Development*: *Four weeks* to add new features and to enhance existing + ones; + +* *Stabilisation*: *Two weeks* to fix bugs, prepare the release, and wait + for the whole Rsyslog ecosystem (third-party libraries, bundles, and + projects using Rsyslog) to catch up. + +During the development phase, any new feature can be reverted if it won't be +finished in time or if it won't be stable enough to be included in the current +final release. + + +.. _Semantic Versioning: http://semver.org/ +.. _Git repository: https://github.com/rsyslog/rsyslog diff --git a/source/proposals/big_restructuring/contributing/documentation/index.rst b/source/proposals/big_restructuring/contributing/documentation/index.rst new file mode 100644 index 0000000..e684599 --- /dev/null +++ b/source/proposals/big_restructuring/contributing/documentation/index.rst @@ -0,0 +1,3 @@ +How to contribute to the documentation +====================================== + diff --git a/source/proposals/big_restructuring/contributing/index.rst b/source/proposals/big_restructuring/contributing/index.rst new file mode 100644 index 0000000..d4d99b5 --- /dev/null +++ b/source/proposals/big_restructuring/contributing/index.rst @@ -0,0 +1,9 @@ +Contributing +============ + +.. toctree:: + + code/index + documentation/index + community/index + diff --git a/source/proposals/big_restructuring/cookbook/index.rst b/source/proposals/big_restructuring/cookbook/index.rst new file mode 100644 index 0000000..8291e44 --- /dev/null +++ b/source/proposals/big_restructuring/cookbook/index.rst @@ -0,0 +1,7 @@ +The Cookbook +============ + +.. toctree:: + + templates/index + setup/index diff --git a/source/proposals/big_restructuring/cookbook/setup/centralised_logging_logstash.rst b/source/proposals/big_restructuring/cookbook/setup/centralised_logging_logstash.rst new file mode 100644 index 0000000..b33e9e8 --- /dev/null +++ b/source/proposals/big_restructuring/cookbook/setup/centralised_logging_logstash.rst @@ -0,0 +1,3 @@ +Centralised logging with Logstash/ElasticSearch/Kibana +====================================================== + diff --git a/source/proposals/big_restructuring/cookbook/setup/index.rst b/source/proposals/big_restructuring/cookbook/setup/index.rst new file mode 100644 index 0000000..def615e --- /dev/null +++ b/source/proposals/big_restructuring/cookbook/setup/index.rst @@ -0,0 +1,7 @@ +Setup Cookbooks +=============== + + +.. toctree:: + + centralised_logging_logstash diff --git a/source/proposals/big_restructuring/cookbook/templates/index.rst b/source/proposals/big_restructuring/cookbook/templates/index.rst new file mode 100644 index 0000000..1b3e14e --- /dev/null +++ b/source/proposals/big_restructuring/cookbook/templates/index.rst @@ -0,0 +1,8 @@ +Templates +========= + +.. toctree:: + + rfc3164 + rfc5424 + diff --git a/source/proposals/big_restructuring/cookbook/templates/rfc3164.rst b/source/proposals/big_restructuring/cookbook/templates/rfc3164.rst new file mode 100644 index 0000000..7045fb1 --- /dev/null +++ b/source/proposals/big_restructuring/cookbook/templates/rfc3164.rst @@ -0,0 +1,3 @@ +Configuring an RFC 3164 Template with Json message +================================================== + diff --git a/source/proposals/big_restructuring/cookbook/templates/rfc5424.rst b/source/proposals/big_restructuring/cookbook/templates/rfc5424.rst new file mode 100644 index 0000000..1b60645 --- /dev/null +++ b/source/proposals/big_restructuring/cookbook/templates/rfc5424.rst @@ -0,0 +1,3 @@ +Configuring an RFC 5424 Template with Json message +================================================== + diff --git a/source/proposals/big_restructuring/documentation_review.rst b/source/proposals/big_restructuring/documentation_review.rst new file mode 100644 index 0000000..b257bfd --- /dev/null +++ b/source/proposals/big_restructuring/documentation_review.rst @@ -0,0 +1,83 @@ +Rsyslog Documentation Review Proposal +===================================== + +Currently the Rsyslog documentation is spread over many places. It's not logical +and well-organized as well. The objective of this proposal is to address those issues +and establish a procedure for further development of the documentation. + +.. note:: + + We SHOULD NOT write examples using mixed formats, RainerScripts and legacy. It confused + the readers. We can provide them in both formats, but should not mix them. + + +Compile information from current sources of information +------------------------------------------------------- + +Below are listed the official locations where documentation about Rsyslog can be found. + + * Wiki: http://wiki.rsyslog.com/index.php/Main_Page + * Rainer's blog: https://rainer.gerhards.net/2012/10/how-to-use-rsyslogs-ruleset-and-call.html + * Issues: https://github.com/rsyslog/rsyslog + * docs: https://github.com/rsyslog/rsyslog-doc + * Forum: http://kb.monitorware.com/configuration-f36.html + * https://www.youtube.com/user/rainergerhards + + +Add a Cookbook Section +---------------------- + +We should create some cookbooks to help people get started with Rsyslog. +Some candidates to be a cookbook are below. + + * http://sickbits.net/log-storage-and-analysis-infrastructure-reliable-logging-and-analysis-with-rsyslog-and-relp/ + * http://kb.monitorware.com/omfile-with-dynfile-syslogfacility-text-t12515.html + * http://www.freeipa.org/page/Howto/Centralised_Logging_with_Logstash/ElasticSearch/Kibana + +Add a subsection called "processing logs from". We'd place articles that'd would help people with specific +common scenarios for a specific log sender application. + +Add a Reference Section +----------------------- + +This section would have all the reference configuration of all possible tags, in both formats, RainerScript +and legacy. + + +Write articles that address common problems +------------------------------------------- + +Some of the common are following. + + * https://github.com/rsyslog/rsyslog/issues/160 + * http://kb.monitorware.com/nginx-logging-rsyslog-t12359.html + * http://trac.nginx.org/nginx/ticket/677 + + +Extra +----- + +Some resources worth taking a look. + + * https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7/html/System_Administrators_Guide/ch-Viewing_and_Managing_Log_Files.html + * https://www.usenix.org/system/files/login/articles/06_lang-online.pdf + * https://media.readthedocs.org/pdf/rsyslog/latest/rsyslog.pdf + * http://download.rsyslog.com/rainerscript2_rsyslog.conf + * http://people.redhat.com/pvrabec/rpms/rsyslog/rsyslog-example.conf + * http://www.rsyslog.com/doc/syslog_parsing.html + + +Initial Summary +--------------- + + - Troubleshooting + + * http://www.rsyslog.com/how-can-i-check-the-config/ + +Proposed Documentation Structure +-------------------------------- + + toctree:: + + new_documentation/index + diff --git a/source/proposals/big_restructuring/index.rst b/source/proposals/big_restructuring/index.rst new file mode 100644 index 0000000..a75c9f5 --- /dev/null +++ b/source/proposals/big_restructuring/index.rst @@ -0,0 +1,15 @@ +Rsyslog documentation +===================== + +Below is the proposed documentation structure. It's initial content is the +current documentation available, just organized differently. + +.. toctree:: + + book/index + cookbook/index + reference/index + contributing/index + documentation_review.rst + + diff --git a/source/proposals/big_restructuring/reference/action.rst b/source/proposals/big_restructuring/reference/action.rst new file mode 100644 index 0000000..7ad1aaf --- /dev/null +++ b/source/proposals/big_restructuring/reference/action.rst @@ -0,0 +1,3 @@ +Action Configuration Reference +============================== + diff --git a/source/proposals/big_restructuring/reference/global.rst b/source/proposals/big_restructuring/reference/global.rst new file mode 100644 index 0000000..cc464fd --- /dev/null +++ b/source/proposals/big_restructuring/reference/global.rst @@ -0,0 +1,3 @@ +Global Configuration Reference +============================== + diff --git a/source/proposals/big_restructuring/reference/index.rst b/source/proposals/big_restructuring/reference/index.rst new file mode 100644 index 0000000..4583a93 --- /dev/null +++ b/source/proposals/big_restructuring/reference/index.rst @@ -0,0 +1,11 @@ +Configuration Reference +======================= + +.. toctree:: + + module + input + action + parser + global + timezone diff --git a/source/proposals/big_restructuring/reference/input.rst b/source/proposals/big_restructuring/reference/input.rst new file mode 100644 index 0000000..f1dd84d --- /dev/null +++ b/source/proposals/big_restructuring/reference/input.rst @@ -0,0 +1,3 @@ +Input Configuration Reference +============================= + diff --git a/source/proposals/big_restructuring/reference/module.rst b/source/proposals/big_restructuring/reference/module.rst new file mode 100644 index 0000000..3876f37 --- /dev/null +++ b/source/proposals/big_restructuring/reference/module.rst @@ -0,0 +1,3 @@ +Module Configuration Reference +============================== + diff --git a/source/proposals/big_restructuring/reference/parser.rst b/source/proposals/big_restructuring/reference/parser.rst new file mode 100644 index 0000000..c9e6dc6 --- /dev/null +++ b/source/proposals/big_restructuring/reference/parser.rst @@ -0,0 +1,3 @@ +Parser Configuration Reference +============================== + diff --git a/source/proposals/big_restructuring/reference/timezone.rst b/source/proposals/big_restructuring/reference/timezone.rst new file mode 100644 index 0000000..34db014 --- /dev/null +++ b/source/proposals/big_restructuring/reference/timezone.rst @@ -0,0 +1,3 @@ +Timezone Configuration Reference +================================ + diff --git a/source/proposals/big_restructuring/toc_screenshot.png b/source/proposals/big_restructuring/toc_screenshot.png Binary files differnew file mode 100644 index 0000000..b474c49 --- /dev/null +++ b/source/proposals/big_restructuring/toc_screenshot.png diff --git a/source/proposals/index.rst b/source/proposals/index.rst new file mode 100644 index 0000000..41c106a --- /dev/null +++ b/source/proposals/index.rst @@ -0,0 +1,9 @@ +Proposals +========= + +.. toctree:: + :maxdepth: 2 + + version_naming + lookup_tables + big_restructuring/index diff --git a/source/proposals/lookup_tables.rst b/source/proposals/lookup_tables.rst new file mode 100644 index 0000000..f61d673 --- /dev/null +++ b/source/proposals/lookup_tables.rst @@ -0,0 +1,240 @@ +Lookup Tables +============= + +**NOTE: this is proposed functionality, which is NOT YET IMPLEMENTED!** + +**Lookup tables are a powerful construct to obtain "class" information +based on message content (e.g. to build log file names for different +server types, departments or remote offices).** + +The base idea is to use a message variable as an index into a table +which then returns another value. For example, $fromhost-ip could be +used as an index, with the table value representing the type of server +or the department or remote office it is located in. A main point with +lookup tables is that the lookup is very fast. So while lookup tables +can be emulated with if-elseif constructs, they are generally much +faster. Also, it is possible to reload lookup tables during rsyslog +runtime without the need for a full restart. + +The lookup tables itself exists in a separate configuration file (one +per table). This file is loaded on rsyslog startup and when a reload is +requested. + +There are different types of lookup tables: + +- **string** - the value to be looked up is an arbitrary string. Only + exact some strings match. +- **array** - the value to be looked up is an integer number from a + consecutive set. The set does not need to start at zero or one, but + there must be no number missing. So, for example 5,6,7,8,9 would be a + valid set of index values, while 1,2,4,5 would not be (due to missing + 2). A match happens if the requested number is present. +- **sparseArray** - the value to be looked up is an integer value, but + there may be gaps inside the set of values (usually there are large + gaps). A typical use case would be the matching of IPv4 address + information. A match happens on the first value that is less than or + equal to the requested value. + +Note that index integer numbers are represented by unsigned 32 bits. + +Lookup tables can be access via the lookup() built-in function. The core +idea is to set a local variable to the lookup result and later on use +that local variable in templates. + +More details on usage now follow. + +Lookup Table File Format +------------------------ + +Lookup table files contain a single JSON object. This object contains of +a header and a table part. + +Header +~~~~~~ + +The header is the top-level json. It has parameters "version", "nomatch", +and "type". The version parameter must be given and must always be one +for this version of rsyslog. The nomatch parameter is optional. If +specified, it contains the value to be used if lookup() is provided an +index value for which no entry exists. The default for "nomatch" is the +empty string. Type specifies the type of lookup to be done. + +Table +~~~~~ + +This must be an array of elements, even if only a single value exists +(for obvious reasons, we do not expect this to occur often). Each array +element must contain two fields "index" and "value". + +Example +~~~~~~~ + +This is a sample of how an ip-to-office mapping may look like: + +:: + + { "version":1, "nomatch":"unk", "type":"string", + "table":[ {"index":"10.0.1.1", "value":"A" }, + {"index":"10.0.1.2", "value":"A" }, + {"index":"10.0.1.3", "value":"A" }, + {"index":"10.0.2.1", "value":"B" }, + {"index":"10.0.2.2", "value":"B" }, + {"index":"10.0.2.3", "value":"B" } + ] + } + +Note: if a different IP comes in, the value "unk" is returned thanks to +the nomatch parameter in the first line. + +RainerScript Statements +----------------------- + +lookup\_table() Object +~~~~~~~~~~~~~~~~~~~~~~ + +This statement defines and initially loads a lookup table. Its format is +as follows: + +:: + + lookup_table(name="name" file="/path/to/file" reloadOnHUP="on|off") + +Parameters +^^^^^^^^^^ + +- **name** (mandatory) + + Defines the name of lookup table for further reference inside the + configuration. Names must be unique. Note that it is possible, though + not advisible, to have different names for the same file. +- **file** (mandatory) + + Specifies the full path for the lookup table file. This file must be + readable for the user rsyslog is run under (important when dropping + privileges). It must point to a valid lookup table file as described + above. +- **reloadOnHUP** (optional, default "on") + + Specifies if the table shall automatically be reloaded as part of + HUP processing. For static tables, the default is "off" and + specifying "on" triggers an error message. Note that the default of + "on" may be somewhat suboptimal performance-wise, but probably is + what the user intuitively expects. Turn it off if you know that you + do not need the automatic reload capability. + +lookup() Function +~~~~~~~~~~~~~~~~~ + +This function is used to actually do the table lookup. Format: + +:: + + lookup("name", indexvalue) + +Parameters +^^^^^^^^^^ + +- **return value** + + The function returns the string that is associated with the given + indexvalue. If the indexvalue is not present inside the lookup table, + the "nomatch" string is returned (or an empty string if it is not + defined). +- **name** (constant string) + + The lookup table to be used. Note that this must be specified as a + constant. In theory, variable table names could be made possible, but + their runtime behaviour is not as good as for static names, and we do + not (yet) see good use cases where dynamic table names could be + useful. +- **indexvalue** (expression) + + The value to be looked up. While this is an arbitrary RainerScript + expression, it's final value is always converted to a string in order + to conduct the lookup. For example, "lookup(table, 3+4)" would be + exactly the same as "lookup(table, "7")". In most cases, indexvalue + will probably be a single variable, but it could also be the result + of all RainerScript-supported expression types (like string + concatenation or substring extraction). Valid samples are + "lookup(name, $fromhost-ip & $hostname)" or "lookup(name, + substr($fromhost-ip, 0, 5))" as well as of course the usual + "lookup(table, $fromhost-ip)". + +load\_lookup\_table Statement +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +**Note: in the final implementation, this MAY be implemented as an +action. This is a low-level decesion that must be made during the detail +development process. Parameters and semantics will remain the same of +this happens.** + +This statement is used to reload a lookup table. It will fail if the +table is static. While this statement is executed, lookups to this table +are temporarily blocked. So for large tables, there may be a slight +performance hit during the load phase. It is assume that always a +triggering condition is used to load the table. + +:: + + load_lookup_table(name="name" errOnFail="on|off" valueOnFail="value") + +Parameters +^^^^^^^^^^ + +- **name** (string) + + The lookup table to be used. +- **errOnFail** (boolean, default "on") + + Specifies whether or not an error message is to be emitted if there + are any problems reloading the lookup table. +- **valueOnFail** (optional, string) + + This parameter affects processing if the lookup table cannot be + loaded for some reason: If the parameter is not present, the previous + table will be kept in use. If the parameter is given, the previous + table will no longer be used, and instead an empty table be with + nomath=valueOnFail be generated. In short, that means when the + parameter is set and the reload fails, all matches will always return + what is specified in valueOnFail. + +Usage example +~~~~~~~~~~~~~ + +For clarity, we show only those parts of rsyslog.conf that affect lookup +tables. We use the remote office example that an example lookup table +file is given above for. + +:: + + lookup_table(name="ip2office" file="/path/to/ipoffice.lu" + reloadOnHUP="off") + + + template(name="depfile" type="string" + string="/var/log/%$usr.dep%/messages") + + set $usr.dep = lookup("ip2office", $fromhost-ip); + action(type="omfile" dynfile="depfile") + + # support for reload "commands" + if $fromhost-ip == "10.0.1.123" + and $msg contains "reload office lookup table" + then + load_lookup_table(name="ip2office" errOnFail="on") + +Note: for performance reasons, it makes sense to put the reload command +into a dedicated ruleset, bound to a specific listener - which than +should also be sufficiently secured, e.g. via TLS mutual auth. + +Implementation Details +---------------------- + +The lookup table functionality is implemented via highly efficient +algorithms. The string lookup has O(log n) time complexity. The array +lookup is O(1). In case of sparseArray, we have O(log n). + +To preserve space and, more important, increase cache hit performance, +equal data values are only stored once, no matter how often a lookup +index points to them. + diff --git a/source/proposals/version_naming.rst b/source/proposals/version_naming.rst new file mode 100644 index 0000000..7a0e7f2 --- /dev/null +++ b/source/proposals/version_naming.rst @@ -0,0 +1,150 @@ +Version Naming +============== + +This is the proposal on how versions should be named in the future: + +Rsyslog version naming has undergone a number of changes in the past. +Our sincere hopes is that the scheme outlined here will serve us well +for the future. In general, a three-number versioning scheme with a +potential development state indication is used. It follows this pattern: + +major.minor.patchlevel[-devstate] + +where devstate has some further structure: +-<releaseReason><releaseNumber> + +All stable builds come without the devstate part. All unstable +development version come with it. + +The major version is incremented whenever something really important +happens. A single new feature, even if important, does not justify an +increase in the major version. There is no hard rule when the major +version needs an increment. It mostly is a soft factor, when the +developers and/or the community think there has been sufficient change +to justify that. Major version increments are expected to happen quite +infrequently, maybe around once a year. A major version increment has +important implications from the support side: without support contracts, +the current major version's last stable release and the last stable +release of the version immediately below it are supported (Adiscon, the +rsyslog sponsor, offers `support contracts <http://www.rsyslog.com/professional-services/>`_ +covering all other versions). + +The minor version is incremented whenever a non-trivial new feature is +planned to be added. Triviality of a feature is simply determined by +time estimated to implement a feature. If that's more than a few days, +it is considered a non-trivial feature. Whenever a new minor version is +begun, the desired feature is identified and will be the primary focus +of that major.minor version. Trivial features may justify a new minor +version if they either do not look trivial from the user's point of view +or change something quite considerable (so we need to alert users). A +minor version increment may also be done for some other good reasons +that the developers have. + +The patchlevel is incremented whenever there is a bugfix or very minor +feature added to a (stable or development) release. + +The devstate is important during development of a feature. It helps the +developers to release versions with new features to the general public +and in the hope that this will result in some testing. To understand how +it works, we need to look at the release cycle: As already said, at the +start of a new minor version, a new non-trivial feature to be +implemented in that version is selected. Development on this feature +begins. At the current pace of development, getting initial support for +such a non-trivial feature typically takes between two and four weeks. +During this time, new feature requests come in. Also, we may find out +that it may be just the right time to implement some not yet targeted +feature requests. A reason for this is that the minor release's feature +focus is easier to implement if the other feature is implemented first. +This is a quite common thing to happen. So development on the primary +focus may hold for a short period while we implement something else. +Even unrelated, but very trivial feature requests (maybe an hour's worth +of time to implement), may be done in between. Once we have implemented +these things, we would like to release as quickly as possible (even more +if someone has asked for the feature). So we do not like to wait for the +original focus feature to be ready (what could take maybe three more +weeks). As a result, we release the new features. But that version will +also include partial code of the focus feature. Typically this doesn't +hurt as long as noone tries to use it (what of course would miserably +fail). But still, part of the new code is already in it. When we release +such a "minor-feature enhanced" but "focus-feature not yet completed" +version, we need a way to flag it. In current thinking, that is using a +"-mf<version>" devstate in the version number ("mf" stands for "minor +feature"). Version numbers for -mf releases start at 0 for the first +release and are monotonically incremented. Once the focus feature has +been fully implemented, a new version now actually supporting that +feature will be released. Now, the release reason is changed to the +well-know "-rc<version>" where "rc" stands for release candidate. For +the first release candidate, the version starts at 0 again and is +incremented monotonically for each subsequent release. Please note that +a -rc0 may only have bare functionality but later -rc's have a richer +one. If new minor features are implemented and released once we have +reached rc stage, still a new rc version is issued. The difference +between "mf" and "rc" is simply the presence of the desired feature. No +support is provided for -mf versions once the first -rc version has been +released. And only the most current -rc version is supported. + +The -rc is removed and the version declared stable when we think it has +undergone sufficient testing and look sufficiently well. Then, it'll +turn into a stable release. Stable minor releases never receive +non-trivial new features. There may be more than one -rc releases +without a stable release present at the same time. In fact, most often +we will work on the next minor development version while the previous +minor version is still a -rc because it is not yet considered +sufficiently stable. + +Note: the absence of the -devstate part indicates that a release is +stable. Following the same logic, any release with a -devstate part is +unstable. + +A quick sample: + +4.0.0 is the stable release. We begin to implement relp, moving to +major.minor to 4.1. While we develop it, someone requests a trivial +feature, which we implement. We need to release, so we will have +4.1.0-mf0. Another new feature is requested, move to 4.1.0-mf2. A first +version of RELP is implemented: 4.1.0-rc0. A new trivial feature is +implemented: 4.1.0-rc1. Relp is being enhanced: 4.1.0-rc2. We now feel +RELP is good enough for the time being and begin to implement TLS on +plain /Tcp syslog: logical increment to 4.2. Now another new feature in +that tree: 4.2.0-mf0. Note that we now have 4.0.0 (stable) and 4.1.0-rc2 +and 4.1.0-mf0 (both devel). We find a big bug in RELP coding. Two new +releases: 4.1.0-rc3, 4.2.0-mf1 (the bug fix acts like a non-focus +feature change). We release TLS: 4.2.0-rc0. Another RELP bug fix +4.1.0-rc4, 4.2.0-rc1. After a while, RELP is matured: 4.1.0 (stable). +Now support for 4.0.x stable ends. It, however, is still provided for +3.x.x (in the actual case 2.x.x, because v3 was under the old naming +scheme and now stable v3 was ever released). + +This is how it is done so far: + +This document briefly outlines the strategy for naming versions. It +applies to versions 1.0.0 and above. Versions below that are all +unstable and have a different naming schema. + +**Please note that version naming is currently being changed. There is a +`blog post about future rsyslog +versions <https://rainer.gerhards.net/2007/08/on-rsyslog-versions.html>`_.** + +The major version is incremented whenever a considerate, major features +have been added. This is expected to happen quite infrequently. + +The minor version number is incremented whenever there is "sufficient +need" (at the discretion of the developers). There is a notable +difference between stable and unstable branches. The **stable branch** +always has a minor version number in the range from 0 to 9. It is +expected that the stable branch will receive bug and security fixes +only. So the range of minor version numbers should be quite sufficient. + +For the **unstable branch**, minor version numbers always start at 10 +and are incremented as needed (again, at the discretion of the +developers). Here, new minor versions include both fixes as well as new +features (hopefully most of the time). They are expected to be released +quite often. + +The patch level (third number) is incremented whenever a really minor +thing must be added to an existing version. This is expected to happen +quite infrequently. + +In general, the unstable branch carries all new development. Once it +concludes with a sufficiently-enhanced, quite stable version, a new +major stable version is assigned. diff --git a/source/queue_analogy_tv.png b/source/queue_analogy_tv.png Binary files differnew file mode 100644 index 0000000..fedcb55 --- /dev/null +++ b/source/queue_analogy_tv.png diff --git a/source/rainerscript/.control_structures.rst.swp b/source/rainerscript/.control_structures.rst.swp Binary files differnew file mode 100644 index 0000000..1b9cabe --- /dev/null +++ b/source/rainerscript/.control_structures.rst.swp diff --git a/source/rainerscript/.rainerscript_call.rst.swp b/source/rainerscript/.rainerscript_call.rst.swp Binary files differnew file mode 100644 index 0000000..209c6ba --- /dev/null +++ b/source/rainerscript/.rainerscript_call.rst.swp diff --git a/source/rainerscript/configuration_objects.rst b/source/rainerscript/configuration_objects.rst new file mode 100644 index 0000000..580d641 --- /dev/null +++ b/source/rainerscript/configuration_objects.rst @@ -0,0 +1,81 @@ +configuration objects +===================== + +.. note:: + + Configuration object parameters are case-insensitive. + +Common Parameters +----------------- + +config.enabled +^^^^^^^^^^^^^^ + +.. versionadded:: 8.33.0 + +All configuration objects have a ``config.enabled`` parameter. +For auto-generated configs, it is useful to have the ability to disable some +config constructs even though they may be specified inside the config. This +can be done via the ``config.enabled`` parameter. +If set to ``on`` or not specified, the construct will be +used, if set to any other value, it will be ignored. +This can be used together with the backtick functionality to enable or +disable parts of the configuration from either a file or environment variable. + +Example: + +Let's say we want to conditionally load a module. Environment variable +``LOAD_IMPTCP`` will be either unset or ``off`` . +Then we can use this config construct: + +.. code-block:: none + :emphasize-lines: 2 + + module(load="imptcp" + config.enabled=`echo $LOAD_IMPTCP`) + +If the variable is set to ``off``, the module will **not** be loaded. + +Objects +------- + +action() +^^^^^^^^ + +The :doc:`action <../configuration/actions>` object is the primary means of +describing actions to be carried out. + +global() +^^^^^^^^ + +This is used to set global configuration parameters. For details, please +see the :doc:`rsyslog global configuration object <global>`. + +input() +^^^^^^^ + +The :doc:`input <../configuration/input>` object is the primary means of +describing inputs, which are used to gather messages for rsyslog processing. + +module() +^^^^^^^^ + +The module object is used to load plugins. + +parser() +^^^^^^^^ + +The :doc:`parser <../configuration/parser>` object is used to define +custom parser objects. + +timezone() +^^^^^^^^^^ + +The :doc:`timezone <../configuration/timezone>` object is used to define +timezone settings. + +include() +^^^^^^^^^ + +The :doc:`include <include>` object is use to include configuration snippets +stored elsewhere into the configuration. diff --git a/source/rainerscript/constant_strings.rst b/source/rainerscript/constant_strings.rst new file mode 100644 index 0000000..ee6a51d --- /dev/null +++ b/source/rainerscript/constant_strings.rst @@ -0,0 +1,83 @@ +String Constants +================ + +String constants are necessary in any scripting language. They provide +values that are evaluated at startup and never change during rsyslog's +run. + +Uses +---- +String constants are necessary in many places: comparisons, +configuration parameter values and function arguments, to name a few +important ones. + +In string constants, special characters are escaped by prepending a +backslash in front of them -- just in the same way this is done in the C +programming language or PHP. + +If in doubt how to properly escape, use the `RainerScript String Escape +Online +Tool <http://www.rsyslog.com/rainerscript-constant-string-escaper/>`_. + +Types +----- + +Rsyslog provides different types of string constants, closely inspired +by the shell: + +- single quotes + + Values are used unaltered, except for escape sequences, which are + escaped. + +- double quotes + + Right now, equivalent to single quotes, but $ signs need to be escaped. + If not escaped, a syntax error will be generated and rsyslog startup + be aborted in most cases. + The idea is to support environment variables just like the shell does + in later releases. + +- backticks + + This was added in 8.33.0. The idea is to provide a useful subset of + what the shell does. Right now, only the following is supported: + + - `echo $VARNAME` - It will evaluate the environment variable and use + it as string constant. If the variable is not found, an empty string + is generated (this is **not** an error). + + Starting with 8.37.0, the `echo` case has been enhanced. It is now + more along the lines of what bash does. It supports multiple + environment variable expansions as well as constant text + between them. + + An example: + + * env SOMEPATH is set to "/var/log/custompath" + * config is: param=echo $SOMEPATH/myfile + * param than is expanded to "/var/log/custompath/myfile" + + Note, however, that some common bash features are not supported. + Most importantly, `${VAR}` does not work. Also, environment variables + are only terminated by whitespace or `/`. Neither are things like + `$(pwd)` supported. The idea of this parameter is not to provide a + full-blown bash-equivalent, but provide some functionality that is + usually considered useful for customizing rsyslog configuration with + outside data. That said, we are still interested in extending the + coverage if clear need and reasoning is provided. + + - `cat filename` - It will evaluate to the content of the given file. + Only a single file name is supported. If the file is not readable, + it will evaluate to an empty string. + + Any other construct will currently lead to an error message. + Note that there must be exactly one space between "echo" or "cat" and + the other parameter. + + Backticks are especially useful for configuration files that are + auto-generated but need to contain a small set of special functionality. + + For an example of this in action, have a look at the rsyslog docker + appliance available at + https://github.com/rsyslog/rsyslog-docker/tree/master/appliance/alpine. diff --git a/source/rainerscript/control_structures.rst b/source/rainerscript/control_structures.rst new file mode 100644 index 0000000..12ce430 --- /dev/null +++ b/source/rainerscript/control_structures.rst @@ -0,0 +1,138 @@ +****************** +Control Structures +****************** + +Control structures in RainerScript are similar in semantics to a lot +of other mainstream languages such as C, Java, Javascript, Ruby, +Bash etc. +So this section assumes the reader is familiar with semantics of such +structures, and goes about describing RainerScript implementation in +usage-example form rather than by formal-definition and +detailed semantics documentation. + +RainerScript supports following control structures: + +if +== + +.. code-block:: none + + if ($msg contains "important") then { + if ( $.foo != "" ) then set $.foo = $.bar & $.baz; + action(type="omfile" file="/var/log/important.log" template="outfmt") + } + + +if/else-if/else +=============== + +.. code-block:: none + + if ($msg contains "important") then { + set $.foo = $.bar & $.baz; + action(type="omfile" file="/var/log/important.log" template="outfmt") + } else if ($msg startswith "slow-query:") then { + action(type="omfile" file="/var/log/slow_log.log" template="outfmt") + } else { + set $.foo = $.quux; + action(type="omfile" file="/var/log/general.log" template="outfmt") + } + + +foreach +======= + +A word of caution first: there often is a misunderstanding in regard to foreach: +this construct only works on JSON structures. Actually, we should have rejected the +proposal for "foreach" at the time it was made, but now it is too late. + +So please be warned: there is no general concept of an "array" inside the script +language. This is intentional as we do not wanted to get it too complex. +Where you can use arrays is for some config objects and a select set of comparisons, +but nowhere else. + +If you parsed JSON, foreach can iterate both JSON arrays and JSON objects inside this +parsed JSON. As opposed to JSON array-iteration (which is ordered), JSON object-iteration +accesses key-values in arbitrary order (is unordered). + +For the foreach invocation below: + +.. code-block:: none + + foreach ($.i in $.collection) do { + ... + } + + +Say ``$.collection`` holds an array ``[1, "2", {"a": "b"}, 4]``, value +of ``$.i`` across invocations would be ``1``, ``"2"``, ``{"a" : "b"}`` +and ``4``. + +Note that ``$.collection`` must have been parsed from JSON (via mmjsonparse). + +When ``$.collection`` holds an object +``{"a": "b", "c" : [1, 2, 3], "d" : {"foo": "bar"}}``, value of ``$.i`` +across invocations would be ``{"key" : "a", "value" : "b"}``, +``{"key" : "c", "value" : [1, 2, 3]}`` and +``{"key" : "d", "value" : {"foo" : "bar"}}`` (not necessarily in the that +order). In this case key and value will need to be accessed as ``$.i!key`` +and ``$.i!value`` respectively. + + + +Here is an example of a nested foreach statement: + +.. code-block:: none + + foreach ($.quux in $!foo) do { + action(type="omfile" file="./rsyslog.out.log" template="quux") + foreach ($.corge in $.quux!bar) do { + reset $.grault = $.corge; + action(type="omfile" file="./rsyslog.out.log" template="grault") + if ($.garply != "") then + set $.garply = $.garply & ", "; + reset $.garply = $.garply & $.grault!baz; + } + } + +Again, the itereted items must have been created by parsing JSON. + +Please note that asynchronous-action calls in foreach-statement body should +almost always set ``action.copyMsg`` to ``on``. This is because action calls +within foreach usually want to work with the variable loop populates (in the +above example, ``$.quux`` and ``$.corge``) which causes message-mutation and +async-action must see message as it was in a certain invocation of loop-body, +so they must make a copy to keep it safe from further modification as iteration +continues. For instance, an async-action invocation with linked-list based +queue would look like: + +.. code-block:: none + + foreach ($.quux in $!foo) do { + action(type="omfile" file="./rsyslog.out.log" template="quux + queue.type="linkedlist" action.copyMsg="on") + } + +Note well where foreach does **not** work: + +.. code-block:: none + + set $.noarr = ["192.168.1.1", "192.168.2."]; + foreach ($.elt in $.noarr) do { + ... + } + +This is the case because the assignment does not create a JSON array. + + +call +==== + +Details here: :doc:`rainerscript_call` + + +continue +======== + +A NOP, useful e.g. inside the ``then`` part of an if-structure. + diff --git a/source/rainerscript/data_types.rst b/source/rainerscript/data_types.rst new file mode 100644 index 0000000..cadf722 --- /dev/null +++ b/source/rainerscript/data_types.rst @@ -0,0 +1,9 @@ +Data Types +========== + +RainerScript is a typeless language. That doesn't imply you don't need +to care about types. Of course, expressions like "A" + "B" will not +return a valid result, as you can't really add two letters (to +concatenate them, use the concatenation operator &). However, all type +conversions are automatically done by the script interpreter when there +is need to do so.
\ No newline at end of file diff --git a/source/rainerscript/expressions.rst b/source/rainerscript/expressions.rst new file mode 100644 index 0000000..a3f6060 --- /dev/null +++ b/source/rainerscript/expressions.rst @@ -0,0 +1,25 @@ +Expressions +=========== + +The language supports arbitrary complex expressions. All usual operators +are supported. The precedence of operations is as follows (with +operations being higher in the list being carried out before those lower +in the list, e.g. multiplications are done before additions. + +- expressions in parenthesis +- not, unary minus +- \*, /, % (modulus, as in C) +- +, -, & (string concatenation) +- ==, !=, <>, <, >, <=, >=, contains (strings!), startswith (strings!) +- and +- or + +For example, "not a == b" probably returns not what you intended. The +script processor will first evaluate "not a" and then compare the +resulting boolean to the value of b. What you probably intended to do is +"not (a == b)". And if you just want to test for inequality, we highly +suggest to use "!=" or "<>". Both are exactly the same and are provided +so that you can pick whichever you like best. So inequality of a and b +should be tested as "a <> b". The "not" operator should be reserved to +cases where it actually is needed to form a complex boolean expression. +In those cases, parentheses are highly recommended. diff --git a/source/rainerscript/functions/idx_built-in_functions.rst b/source/rainerscript/functions/idx_built-in_functions.rst new file mode 100644 index 0000000..d2be538 --- /dev/null +++ b/source/rainerscript/functions/idx_built-in_functions.rst @@ -0,0 +1,11 @@ +****************** +Built-in Functions +****************** + +Following functions are available in Rainerscript. + +.. toctree:: + :glob: + :maxdepth: 1 + + rs* diff --git a/source/rainerscript/functions/idx_module_functions.rst b/source/rainerscript/functions/idx_module_functions.rst new file mode 100644 index 0000000..1998b56 --- /dev/null +++ b/source/rainerscript/functions/idx_module_functions.rst @@ -0,0 +1,16 @@ +**************** +Module Functions +**************** + +You can make module functions accessible for the configuration by loading the +corresponding module. Once they are loaded, you can use them like any other +rainerscript function. If more than one function are part of the same module, +all functions will be available once the module is loaded. + + +.. toctree:: + :glob: + :maxdepth: 1 + + mo* + diff --git a/source/rainerscript/functions/index.rst b/source/rainerscript/functions/index.rst new file mode 100644 index 0000000..a40e166 --- /dev/null +++ b/source/rainerscript/functions/index.rst @@ -0,0 +1,27 @@ +********* +Functions +********* + +There are two types of RainerScript functions: built-ins and modules. Built-in +functions can always be called in the configuration. To use module functions, +you have to load the corresponding module first. To do this, add the following +line to your configuration: + +:: + + module(load="<name of module>") + +If more than one function with the same name is present, the function of the +first module loaded will be used. Also, an error message stating this will be +generated. However, the configuration will not abort. Please note that built-in +functions will always be automatically loaded before any modules. Because of this, you +are unable to override any of the built-in functions, since their names are already +in use. The name of a function module starts with fm. + + +.. toctree:: + :glob: + :maxdepth: 2 + + idx_built-in_functions + idx_module_functions diff --git a/source/rainerscript/functions/mo-ffaup.rst b/source/rainerscript/functions/mo-ffaup.rst new file mode 100644 index 0000000..5291c74 --- /dev/null +++ b/source/rainerscript/functions/mo-ffaup.rst @@ -0,0 +1,103 @@ +************ +Faup +************ + + +Description +=========== + +These new functions allow anybody to parse any variable containing URLs, hostnames, DNS queries and such to extract: + - the *scheme* + - the *credentials* (if present) + - the *tld* (with support for second-level TLDs) + - the *domain* (with and without the tld) + - the *subdomain* + - the *full hostname* + - the *port* (if present) + - the *resource* path (if present) + - the *query string* parameters (if present) + - the *fragment* (if present) + +HowTo +----- +The module functions are fairly simple to use, and are divided in 2 classes: +* `faup()` allows to parse the entire URL and return all parts in a complete JSON +* `faup_<field>()` allows to parse the entire URL, but only returns the (potential) value of the requested field as string + +Examples +^^^^^^^^ +Using the `faup()` function +""""""""""""""""""""""""""""""" +The `faup()` is the simplest function to use, simply provide a value or variable (any type) as the only parameter, and the function returns a json object containing every element of the URL. + +*example code:* + +.. code-block:: none + + set $!url = "https://user:pass@www.rsyslog.com:443/doc/v8-stable/rainerscript/functions/mo-faup.html?param=value#faup"; + set $.faup = faup($!url); + + +*$.faup will contain:* + +.. code-block:: none + + { + "scheme": "https", + "credential": "user:pass", + "subdomain": "www", + "domain": "rsyslog.com", + "domain_without_tld": "rsyslog", + "host": "www.rsyslog.com", + "tld": "com", + "port": "443", + "resource_path": "\/doc\/v8-stable\/rainerscript\/functions\/mo-ffaup.html", + "query_string": "?param=value", + "fragment": "#faup" + } + +.. note:: + + This is a classic rsyslog variable, and you can access every sub-key with `$.faup!domain`, `$.faup!resource_path`, etc... + + +Using the `faup_<field>()` functions +"""""""""""""""""""""""""""""""""""""""" +Using the field functions is even simpler: for each field returned by the `faup()` function, there exists a corresponding function to get only that one field. + +For example, if the goal is to recover the domain without the tld, the example above could be modified as follows: + +*example code:* + +.. code-block:: none + + set $!url = "https://user:pass@www.rsyslog.com:443/doc/v8-stable/rainerscript/functions/mo-faup.html?param=value#faup"; + set $.faup = faup_domain_without_tld($!url); + +*$.faup will contain:* + +.. code-block:: none + + rsyslog + +.. note:: + + The returned value is no longer a json object, but a simple string + + +Requirements +============ +This module relies on the `faup <https://github.com/stricaud/faup>`_ library. + +The library should be compiled (see link for instructions on how to compile) and installed on build and runtime machines. + +.. warning:: + + Even if faup is statically compiled to rsyslog, the library still needs an additional file to work properly: the mozilla.tlds stored by the libfaup library in /usr/local/share/faup. It permits to properly match second-level TLDs and allow URLs such as www.rsyslog.co.uk to be correctly parsed into \<rsyslog:domain\>.\<co.uk:tld\> and not \<rsyslog:subdomain\>.\<co:domain\>.\<uk:tld\> + + +Motivations +=========== +Those functions are the answer to a growing problem encountered in Rsyslog when using modules to enrich logs : some mechanics (like lookup tables or external module calls) require "strict" URL/hostname formats that are often not formatted correctly, resulting in lookup failures/misses. + +This ensures getting stable inputs to provide to lookups/modules to enrich logs.
\ No newline at end of file diff --git a/source/rainerscript/functions/mo-hashXX.rst b/source/rainerscript/functions/mo-hashXX.rst new file mode 100644 index 0000000..61bb69a --- /dev/null +++ b/source/rainerscript/functions/mo-hashXX.rst @@ -0,0 +1,42 @@ +****** +HashXX +****** + +Purpose +======= + +Generates hash for a given string. + +hash32(literal_string) / hash32(literal_string, seed) +----------------------------------------------------- + + Generates a 32 bit hash of the given string. + - Seed is an optional parameter with default = 0. + - If seed is not a valid number, then 0 is returned. + +hash64(literal_string) / hash64(literal_string, seed) +----------------------------------------------------- + + Generates a 64 bit hash of the given string. + - Seed is an optional parameter with default = 0. + - If seed is not a valid number, then 0 is returned. + +.. warning:: + + - Default hash implementation is non-crypto. + - To use xxhash enable compile time flag. + + +Example +======= + +.. code-block:: none + + module(load="fmhash") + + set $.hash = hash64($!msg!field_1 & $!msg!field_2 & $!msg!field_3) + set $!tag= $syslogtag & $.hash; + //send out + +.. seealso:: + :doc:`Hash based sampling<../../tutorials/hash_sampling>` diff --git a/source/rainerscript/functions/mo-hashXXmod.rst b/source/rainerscript/functions/mo-hashXXmod.rst new file mode 100644 index 0000000..8fc1d77 --- /dev/null +++ b/source/rainerscript/functions/mo-hashXXmod.rst @@ -0,0 +1,48 @@ +********* +HashXXmod +********* + +Purpose +======= + +Generates a number which is mod of given string's hash. + +hash32mod(literal_string, modulo) / hash32mod(literal_string, modulo, seed) +--------------------------------------------------------------------------- + + Generates a number which is calculated on (32 bit hash of the given string % modulo) + - If modulo is not a valid number, then 0 is returned. + - If modulo is 0, then 0 is returned. + - Seed is an optional parameter with default = 0. + - If seed is not a valid unsigned number, then 0 is returned. + + +hash64mod(literal_string, modulo) / hash64mod(literal_string, modulo, seed) +--------------------------------------------------------------------------- + + Generates a number which is calculated on (64 bit hash of the given string % modulo) + - If modulo is not a valid number, then 0 is returned. + - If modulo is 0, then 0 is returned. + - Seed is an optional parameter with default = 0. + - If seed is not a valid unsigned number, then 0 is returned. + + +.. warning:: + + - Default hash implementation is non-crypto. + - To use xxhash enable compile time flag. + + +Example +======= + +.. code-block:: none + + module(load="fmhash") + + if (hash64mod($!msg!request_id, 100) <= 30) then { + //send out + } + +.. seealso:: + :doc:`Hash based sampling<../../tutorials/hash_sampling>` diff --git a/source/rainerscript/functions/mo-http_request.rst b/source/rainerscript/functions/mo-http_request.rst new file mode 100644 index 0000000..a0b0f22 --- /dev/null +++ b/source/rainerscript/functions/mo-http_request.rst @@ -0,0 +1,39 @@ +************ +HTTP-Request +************ + +Purpose +======= + +http_request(str) + +Performs a http request to target and returns the result of said request. + +.. note:: + + this function is very slow and therefore we suggest using it only seldomly + to insure adequate performance. + + +Example +======= + +The following example performs a http request and writes the returned value +to a file. + + +.. code-block:: none + + module(load="../plugins/imtcp/.libs/imtcp") + module(load="../plugins/fmhttp/.libs/fmhttp") + input(type="imtcp" port="13514") + + template(name="outfmt" type="string" string="%$!%\n") + + if $msg contains "msgnum:" then { + set $.url = "http://www.rsyslog.com/testbench/echo-get.php?content=" & ltrim($msg); + set $!reply = http_request($.url); + action(type="omfile" file="rsyslog.out.log" template="outfmt") + } + + diff --git a/source/rainerscript/functions/mo-unflatten.rst b/source/rainerscript/functions/mo-unflatten.rst new file mode 100644 index 0000000..136251e --- /dev/null +++ b/source/rainerscript/functions/mo-unflatten.rst @@ -0,0 +1,61 @@ +************ +Unflatten +************ + +Purpose +======= + +``<result> = unflatten(<source-tree>, <key-separator-character>);`` + +This function unflattens keys in a JSON object. It provides a way to expand dot-separated fields. + +It allows for instance to produce this: + ``{ "source": { "ip": "1.2.3.4", "port": 443 } }`` + +from this source data: + ``{ "source.ip": "1.2.3.4", "source.port": 443 }`` + + +Example +======= + +Here is a sample use case: + +.. code-block:: none + + module(load="fmunflatten") + + # Say you have the following tree, obtained for instance with mmnormalize. + set $!source.ip = "1.2.3.4"; + set $!source.bytes = 3258; + set $!source.geo.country_iso_code = "FR"; + set $!destination.ip = "4.3.2.1"; + + # Now unflatten the keys in the $! tree. + set $.unflatten = unflatten($!, "."); + + # You may do this to set back safely the result in $! because the function could + # return a default dummy value of 0 (rsyslog number) if $! was not touched (it + # would evaluate to an empty rsyslog string, which is not a JSON datatype). + if (script_error() == 0) then { + unset $!; + set $! = $.unflatten; + unset $.unflatten; + } + +An output of ``$!`` would give this, in pretty-print: + +.. code-block:: none + + { + "source": { + "ip": "1.2.3.4", + "bytes": 3258, + "geo": { + "country_iso_code": "FR" + } + }, + "destination": { + "ip": "4.3.2.1" + } + } diff --git a/source/rainerscript/functions/rs-cnum.rst b/source/rainerscript/functions/rs-cnum.rst new file mode 100644 index 0000000..055a343 --- /dev/null +++ b/source/rainerscript/functions/rs-cnum.rst @@ -0,0 +1,36 @@ +****** +cnum() +****** + +Purpose +======= + +cnum(expr) + +Converts expr to a number (integer). + +.. note:: + + If the expression does not contain a numerical value, the following + rule applies: the best match as the number is returned. For example + "1x234" will return the number 1 and "Test123" will return 0. Zero is + always returned if the there is no number at the start of the string. + This also is the case for empty strings. + + +Example +======= + + + +.. code-block:: none + + cnum(3+2); + +produces + +.. code-block:: none + + 5 + + diff --git a/source/rainerscript/functions/rs-cstr.rst b/source/rainerscript/functions/rs-cstr.rst new file mode 100644 index 0000000..3cf007e --- /dev/null +++ b/source/rainerscript/functions/rs-cstr.rst @@ -0,0 +1,27 @@ +****** +cstr() +****** + +Purpose +======= + +cstr(expr) + +Converts expr to a string value. + + +Example +======= + +In the following example a string is created from the expression. + +.. code-block:: none + + cstr(5*4); + +produces + +.. code-block:: none + + "20" + diff --git a/source/rainerscript/functions/rs-dyn_inc.rst b/source/rainerscript/functions/rs-dyn_inc.rst new file mode 100644 index 0000000..67769cc --- /dev/null +++ b/source/rainerscript/functions/rs-dyn_inc.rst @@ -0,0 +1,35 @@ +********* +dyn_inc() +********* + +Purpose +======= + +dyn_inc(bucket_name_literal_string, str) + +Increments counter identified by ``str`` in dyn-stats bucket identified +by ``bucket_name_literal_string``. Returns 0 when increment is successful, +any other return value indicates increment failed. + +Counters updated here are reported by **impstats**. + +Except for special circumstances (such as memory allocation failing etc), +increment may fail due to metric-name cardinality being under-estimated. +Bucket is configured to support a maximum cardinality (to prevent abuse) +and it rejects increment-operation if it encounters a new(previously unseen) +metric-name(``str``) when full. + +**Read more about it here** :doc:`Dynamic Stats<../../configuration/dyn_stats>` + + +Example +======= + +The following example shows the counter $hostname incremented in the bucket +msg_per_host. + +.. code-block:: none + + dyn_inc("msg_per_host", $hostname) + + diff --git a/source/rainerscript/functions/rs-exec_template.rst b/source/rainerscript/functions/rs-exec_template.rst new file mode 100644 index 0000000..76b07cc --- /dev/null +++ b/source/rainerscript/functions/rs-exec_template.rst @@ -0,0 +1,25 @@ +*************** +exec_template() +*************** + +Purpose +======= + +exec_template(str) + +Sets a variable through the execution of a template. Basically this permits to easily +extract some part of a property and use it later as any other variable. + +**Read more about it here :** `<http://www.rsyslog.com/how-to-use-set-variable-and-exec_template>`_ + +Example +======= + +The following example shows the template being used to extract a part of the message. + +.. code-block:: none + + template(name="extract" type="string" string="%msg:F:5%") + set $!xyz = exec_template("extract"); + + diff --git a/source/rainerscript/functions/rs-exists.rst b/source/rainerscript/functions/rs-exists.rst new file mode 100644 index 0000000..eabffd8 --- /dev/null +++ b/source/rainerscript/functions/rs-exists.rst @@ -0,0 +1,30 @@ +******** +exists() +******** + +Purpose +======= + +exists($!path!varname) + +This function checks if the specified variable exists, in other +words: contains a value. A variable that once was set and later +on unset does also not exist. + +The function accepts a single argument, which needs to be a variable. +It returns 0 if the variable does not exist and 1 otherwise. The +function can be combined with any other expression to form more +complec expressions. + +.. versionadded:: 8.2010.10 + + +Example +======= + +.. code-block:: none + + if exists(!$path!varname) then ... + if not exists($.local!var) then ... + if exists($!triggervar) and $msg contains "something" then ... + diff --git a/source/rainerscript/functions/rs-field.rst b/source/rainerscript/functions/rs-field.rst new file mode 100644 index 0000000..bc3c08b --- /dev/null +++ b/source/rainerscript/functions/rs-field.rst @@ -0,0 +1,64 @@ +******* +field() +******* + +Purpose +======= + +field(str, delim, matchnbr) + +Returns a field-based substring. str is +the string to search, delim is the delimiter and matchnbr is the +match to search for (the first match starts at 1). This works similar +as the field based property-replacer option. Versions prior to 7.3.7 +only support a single character as delimiter character. Starting with +version 7.3.7, a full string can be used as delimiter. If a single +character is being used as delimiter, delim is the numerical ascii +value of the field delimiter character (so that non-printable +characters can by specified). If a string is used as delimiter, a +multi-character string (e.g. "#011") is to be specified. + +.. note:: + + When a single character is specified as string + ``field($msg, ",", 3)`` a string-based extraction is done, which is + more performance intensive than the equivalent single-character + ``field($msg, 44 ,3)`` extraction. + + +Example +======= + +With ascii value of the field delimiter +--------------------------------------- + +Following example returns the third field delimited by space. +In this example $msg will be "field1 field2 field3 field4". + +.. code-block:: none + + set $!usr!field = field($msg, 32, 3); + +produces + +.. code-block:: none + + "field3" + + +With a string as the field delimiter +------------------------------------ + +This example returns the second field delimited by "#011". +In this example $msg will be "field1#011field2#011field3#011field4". + +.. code-block:: none + + set $!usr!field = field($msg, "#011", 2); -- the second field, delimited by "#011" + +produces + +.. code-block:: none + + "field2" + diff --git a/source/rainerscript/functions/rs-format_time.rst b/source/rainerscript/functions/rs-format_time.rst new file mode 100644 index 0000000..aac628e --- /dev/null +++ b/source/rainerscript/functions/rs-format_time.rst @@ -0,0 +1,64 @@ +************* +format_time() +************* + +Purpose +======= + +.. note:: + + This is EXPERIMENTAL code - it may be removed or altered in + later versions than 8.30.0. Please watch the ChangeLog closely for + updates. + +Converts a UNIX timestamp to a formatted RFC 3164 or RFC 3339 date/time string. +The first parameter is expected to be an integer value representing the number of +seconds since 1970-01-01T00:00:0Z (UNIX epoch). The second parameter can be one of +``"date-rfc3164"`` or ``"date-rfc3339"``. The output is a string containing +the formatted date/time. Date/time strings are expressed in **UTC** (no time zone +conversion is provided). + +.. note:: + + If the input to the function is NOT a proper UNIX timestamp, a string + containing the original value of the parameter will be returned instead of a + formatted date/time string. + + +Example +======= + +RFC 3164 timestamp +------------------ + +In the following example the integer representing a UNIX timestamp is +formatted to a rfc-3164 date/time string. + +.. code-block:: none + + format_time(1507165811, "date-rfc3164") + +produces + +.. code-block:: none + + Oct 5 01:10:11 + + +Wrong input +----------- + +In the following example a wrong parameter is given which can't be +formatted and so it is returned unchanged. + +.. code-block:: none + + format_time("foo", "date-rfc3164") + +produces + +.. code-block:: none + + foo + + diff --git a/source/rainerscript/functions/rs-get_property.rst b/source/rainerscript/functions/rs-get_property.rst new file mode 100644 index 0000000..a1536fa --- /dev/null +++ b/source/rainerscript/functions/rs-get_property.rst @@ -0,0 +1,58 @@ +************** +get_property() +************** + +Purpose +======== + +get_property(rsyslog_variable, key_str) + +Provides ability to get a rsyslog variable or property using dynamically evaluated parameters. +The first parameter is a valid rsyslog variable or property, the second parameter is a key string, or index value. + + +Example +======== + +In the following example, a json string is parsed using parse_json(), and placed into the variable ``$!parsed``. +The get_property function is then used to get property fields from ``$!parsed``. + +.. code-block:: none + + set $.ret = parse_json("{\"offsets\": [ { \"a\": 9, \"b\": 0 },\ + { \"a\": 9, \"b\": 3 } ],\ + \"boolval\": true,\ + \"int64val\": 1234567890,\ + \"nullval\": null,\ + \"doubleval\": 12345.67890 }", "\$!parsed"); + + # get different fields from $!parsed here + if $.ret == 0 then { + # dynamically evaluate different fields in $!parsed + + # do dynamic indexing into array + $.index = 1; + # set $.ret = { "a": 9, "b": 3} + set $.ret = get_property($!parsed!offsets, $.index); + + # set $.ret = true; + set $.key = "boolval"; + set $.ret = get_property($!parsed, $.key); + + # null values are evaluated to empty string + # thus below statement will set $.ret to empty string + set $.ret = get_property($!parsed, "nullval"); + + # evaluates to 1234567890 + set $.key = "int64val"; + set $.ret = get_property($!parsed, $.key); + + # using a key variable, evaluates to 12345.67890 + set $key = "doubleval"; + set $.ret = get_property($!parsed, $key); + } + + # example of dynamically building key value + set $.foo!barval = 3; + # set $.bar = 3; + set $.bar = get_property($.foo, "bar" & "val"); diff --git a/source/rainerscript/functions/rs-getenv.rst b/source/rainerscript/functions/rs-getenv.rst new file mode 100644 index 0000000..0035a8b --- /dev/null +++ b/source/rainerscript/functions/rs-getenv.rst @@ -0,0 +1,23 @@ +******** +getenv() +******** + +Purpose +======= + +getenv(str) + +Like the OS call, returns the value of the environment variable, +if it exists. Returns an empty string if it does not exist. + + +Examples +======== + +The following example can be used to build a dynamic filter based on +some environment variable: + +.. code-block:: none + + if $msg contains getenv('TRIGGERVAR') then /path/to/errfile + diff --git a/source/rainerscript/functions/rs-int2hex.rst b/source/rainerscript/functions/rs-int2hex.rst new file mode 100644 index 0000000..29cbbdd --- /dev/null +++ b/source/rainerscript/functions/rs-int2hex.rst @@ -0,0 +1,56 @@ +********* +int2hex() +********* + +Purpose +======= + +int2hex(num) + +Returns a hexadecimal number string of a given positive integer num. + +.. note:: + + When a negative integer is given the return value will be the + `Two's complement <https://en.wikipedia.org/wiki/Two%27s_complement>`_ of + the input number. + + +Example +======= + + +Positive Integer given +---------------------- + +In the following example the hexadecimal number of 61 is returned +as a string. + +.. code-block:: none + + int2hex(61) + +produces + +.. code-block:: none + + 3d + + +Negative Integer given +---------------------- + +This example shows the result on a 64-bit system when a negative +integer such as -13 is put into the function. + +.. code-block:: none + + int2hex(-13) + +produces + +.. code-block:: none + + fffffffffffffff3 + + diff --git a/source/rainerscript/functions/rs-ipv4convert.rst b/source/rainerscript/functions/rs-ipv4convert.rst new file mode 100644 index 0000000..5ab9b16 --- /dev/null +++ b/source/rainerscript/functions/rs-ipv4convert.rst @@ -0,0 +1,52 @@ +*********************** +num2ipv4() / ipv42num() +*********************** + +Purpose +======= + +num2ipv4 +-------- + +num2ipv4(int) + +Converts an integer into an IPv4-address and returns the address as string. +Input is an integer with a value between 0 and 4294967295. The output format +is '>decimal<.>decimal<.>decimal<.>decimal<' and '-1' if the integer input is +invalid or if the function encounters a problem. + + +ipv42num +-------- + +ipv42num(str) + +Converts an IPv4-address into an integer and returns the integer. Input is +a string; the expected address format may include spaces in the beginning +and end, but must not contain any other characters in between (except dots). +If the format does include these, the function results in an error and returns -1. + + +Example +======= + +num2ipv4 +-------- + +This example shows an integer being converted to an ipv4 address. + +.. code-block:: none + + num2ipv4(123456) + + +ipv42num +-------- + +This example shows the parameter fromhost-ip being converted to an integer. + +.. code-block:: none + + ipv42num($fromhost-ip) + + diff --git a/source/rainerscript/functions/rs-is_time.rst b/source/rainerscript/functions/rs-is_time.rst new file mode 100644 index 0000000..42ca727 --- /dev/null +++ b/source/rainerscript/functions/rs-is_time.rst @@ -0,0 +1,66 @@ +********* +is_time() +********* + +Purpose +======= + +is_time(timestamp) +is_time(timestamp, format_str) + +Checks the given timestamp to see if it is a valid date/time string (RFC 3164, +or RFC 3339), or a UNIX timestamp. + +This function returns ``1`` for valid date/time strings and UNIX timestamps, +``0`` otherwise. Additionally, if the input cannot be parsed, or there is +an error, ``script_error()`` will be set to error state. + +The ``format_str`` parameter is optional, and can be one of ``"date-rfc3164"``, +``"date-rfc3339"`` or ``"date-unix"``. If this parameter is specified, the +function will only succeed if the input matches that format. If omitted, the +function will compare the input to all of the known formats (indicated above) +to see if one of them matches. + +.. note:: + + This function does not support unusual RFC 3164 dates/times that + contain year or time zone information. + + +Example +======= + +Only timestamp is given +----------------------- + +The following example shows the output when a valid timestamp is given. + +.. code-block:: none + + is_time("Oct 5 01:10:11") + is_time("2017-10-05T01:10:11+04:00") + is_time(1507165811) + +all produce + +.. code-block:: none + + 1 + + +Timestamp and Format given +-------------------------- + +The following example shows the output when a valid timestamp is given but +the format does not match. + +.. code-block:: none + + is_time("2017-10-05T01:10:11+04:00", "date-unix") + +all produce + +.. code-block:: none + + 0 + diff --git a/source/rainerscript/functions/rs-lookup.rst b/source/rainerscript/functions/rs-lookup.rst new file mode 100644 index 0000000..cdcd563 --- /dev/null +++ b/source/rainerscript/functions/rs-lookup.rst @@ -0,0 +1,33 @@ +******** +lookup() +******** + +Purpose +======= + +lookup(table_name_literal_string, key) + +Lookup tables are a powerful construct to obtain *class* information based +on message content. It works on top of a data-file which maps key (to be looked +up) to value (the result of lookup). + +The idea is to use a message properties (or derivatives of it) as an index +into a table which then returns another value. For example, $fromhost-ip +could be used as an index, with the table value representing the type of +server or the department or remote office it is located in. + +**Read more about it here** :doc:`Lookup Tables<../../configuration/lookup_tables>` + + +Example +======= + +In the following example the hostname is looked up in the given table and +the corresponding value is returned. + +.. code-block:: none + + lookup_table(name="host_bu" file="/var/lib/host_billing_unit_mapping.json") + set $.bu = lookup("host_bu", $hostname); + + diff --git a/source/rainerscript/functions/rs-parse_json.rst b/source/rainerscript/functions/rs-parse_json.rst new file mode 100644 index 0000000..269b587 --- /dev/null +++ b/source/rainerscript/functions/rs-parse_json.rst @@ -0,0 +1,27 @@ +************ +parse_json() +************ + +Purpose +======= + +parse_json(str, container) + +Parses the json string ``str`` and places the resulting json object +into ``container`` where container can be any valid rsyslog variable. +Returns 0 on success and something otherwise if ``str`` does **not** +contain valid json. + + +Example +======= + +In the following example the json string is placed into the variable $!parsed. +The output is placed in variable $.ret + +.. code-block:: none + + set $.ret = parse_json("{ \"c1\":\"data\" }", "\$!parsed"); + + + diff --git a/source/rainerscript/functions/rs-parse_time.rst b/source/rainerscript/functions/rs-parse_time.rst new file mode 100644 index 0000000..434df3d --- /dev/null +++ b/source/rainerscript/functions/rs-parse_time.rst @@ -0,0 +1,44 @@ +************ +parse_time() +************ + +Purpose +======= + +parse_time(timestamp) + +Converts an RFC 3164 or RFC 3339 formatted date/time string to a UNIX timestamp +(an integer value representing the number of seconds since the UNIX epoch: +1970-01-01T00:00:0Z). + +If the input to the function is not a properly formatted RFC 3164 or RFC 3339 +date/time string, or cannot be parsed, ``0`` is returned and ``script_error()`` +will be set to error state. + +.. note:: + + This function does not support unusual RFC 3164 dates/times that + contain year or time zone information. + +.. note:: + + Fractional seconds (if present) in RFC 3339 date/time strings will + be discarded. + + +Example +======= + +In the following example a timestamp is parsed into an integer. + +.. code-block:: none + + parse_time("Oct 5 01:10:11") # Assumes the current year (2017, in this example) + +produces + +.. code-block:: none + + 1507165811 + + diff --git a/source/rainerscript/functions/rs-percentile_observe.rst b/source/rainerscript/functions/rs-percentile_observe.rst new file mode 100644 index 0000000..40bc81f --- /dev/null +++ b/source/rainerscript/functions/rs-percentile_observe.rst @@ -0,0 +1,33 @@ +******************** +percentile_observe() +******************** + +Purpose +======= + +percentile_observe(bucket_name_literal_string, stats_name_literal_string, value) + +Adds an observation, identified by the ``bucket_name_literal_string`` +and ``stats_name_literal_string``, to the observation set. + +Periodically, on an **impstats** reporting interval, percentile and summary metrics are generated +based on the statistics collected. + +Except for special circumstances (such as memory allocation failing etc), +observe calls may fail due to stat-name cardinality being under-estimated. +Bucket is configured to support a maximum cardinality (to prevent abuse) +and it rejects observe-operation if it encounters a new(previously unseen) +stat-name(``str``) when full. + +**Read more about it here** :doc:`Percentile Stats<../../configuration/percentile_stats>` + + +Example +======= + +In the following example, the ``$msg_count`` value is being recorded as a ``msg_per_host`` statistic in the ``host_statistics`` bucket. + + +.. code-block:: none + + percentile_observe("host_statistics", "msg_per_host", $msg_count) diff --git a/source/rainerscript/functions/rs-previous_action_suspended.rst b/source/rainerscript/functions/rs-previous_action_suspended.rst new file mode 100644 index 0000000..b78e448 --- /dev/null +++ b/source/rainerscript/functions/rs-previous_action_suspended.rst @@ -0,0 +1,30 @@ +*************************** +previous_action_suspended() +*************************** + +Purpose +======= + +previous_action_suspended() + +This boolean function returns 1 (true) if the previous action is suspended, +0 (false) otherwise. It can be used to initiate action that shall happen if +a function failed. Please note that an action failure may not be immediately +detected, so the function return value is a bit fuzzy. It is guaranteed, however +that a suspension will be detected with the next batch of messages that is +being processed. + + +Example +======= + +In the following example the if-clause is executed if the previous action +is suspended. + +.. code-block:: none + + action(type="omfwd" protocol="tcp" target="10.1.1.1") + + if previous_action_suspended() then {} + + diff --git a/source/rainerscript/functions/rs-prifilt.rst b/source/rainerscript/functions/rs-prifilt.rst new file mode 100644 index 0000000..c8a88b7 --- /dev/null +++ b/source/rainerscript/functions/rs-prifilt.rst @@ -0,0 +1,23 @@ +********* +prifilt() +********* + +Purpose +======= + +prifilt(constant) + +Mimics a traditional PRI-based filter (like "\*.\*" or "mail.info"). +The traditional filter string must be given as a **constant string**. +Dynamic string evaluation is not permitted (for performance reasons). + + +Example +======= + +In this example true would be returned on an auth event. + +.. code-block:: none + + prifilt("auth,authpriv.*") + diff --git a/source/rainerscript/functions/rs-random.rst b/source/rainerscript/functions/rs-random.rst new file mode 100644 index 0000000..dbf1c15 --- /dev/null +++ b/source/rainerscript/functions/rs-random.rst @@ -0,0 +1,36 @@ +******** +random() +******** + +Purpose +======= + +random(max) + +Generates a random number between 0 and the number specified, though +the maximum value supported is platform specific. + +- If a number is not specified then 0 is returned. +- If 0 is provided as the maximum value, then 0 is returned. +- If the specified value is greater than the maximum supported + for the current platform, then rsyslog will log this in + the debug output and use the maximum value supported instead. + +While the original intent of this function was for load balancing, it +is generic enough to be used for other purposes as well. + +.. warning:: + The random number must not be assumed to be crypto-grade. + +.. versionadded:: 8.12.0 + + +Example +======= + +In the following example a random number between 0 and 123456 is generated. + +.. code-block:: none + + random(123456) + diff --git a/source/rainerscript/functions/rs-re_extract.rst b/source/rainerscript/functions/rs-re_extract.rst new file mode 100644 index 0000000..cd37910 --- /dev/null +++ b/source/rainerscript/functions/rs-re_extract.rst @@ -0,0 +1,38 @@ +************ +re_extract() +************ + +Purpose +======= + +re_extract(expr, re, match, submatch, no-found) + +Extracts data from a string (property) via a regular expression match. +POSIX ERE regular expressions are used. The variable "match" contains +the number of the match to use. This permits to pick up more than the +first expression match. Submatch is the submatch to match (max 50 supported). +The "no-found" parameter specifies which string is to be returned in case +when the regular expression is not found. Note that match and +submatch start with zero. It currently is not possible to extract +more than one submatch with a single call. + +This function performs case-sensitive matching. Use the otherwise-equivalent +:doc:`re_extract_i <rs-re_extract_i>` function to perform case-insensitive +matches. + +.. note:: + + Functions using regular expressions tend to be slow and other options + may be faster. + + +Example +======= + +In the following example the msg object is checked for the regex string. +Only the first match is used and if no match was found an empty string is returned. + +.. code-block:: none + + re_extract($msg,'(5[1-5][0-9]{14})',0,1,"") + diff --git a/source/rainerscript/functions/rs-re_extract_i.rst b/source/rainerscript/functions/rs-re_extract_i.rst new file mode 100644 index 0000000..1eb96c2 --- /dev/null +++ b/source/rainerscript/functions/rs-re_extract_i.rst @@ -0,0 +1,12 @@ +************** +re_extract_i() +************** + +Purpose +======= + +re_extract_i(expr, re, match, submatch, no-found) + +This function is equivalent to `re_extract()` except that +it performs case-insensitive matches. See :doc:`re_extract <rs-re_extract>` +for further details. diff --git a/source/rainerscript/functions/rs-re_match.rst b/source/rainerscript/functions/rs-re_match.rst new file mode 100644 index 0000000..f7036bd --- /dev/null +++ b/source/rainerscript/functions/rs-re_match.rst @@ -0,0 +1,28 @@ +********** +re_match() +********** + +Purpose +======= + +re_match(expr, re) + +Returns 1, if expr matches re, 0 otherwise. Uses POSIX ERE. In contrast to +`re_match_i()` the matching is case-sensitive. + +.. note:: + + Functions using regular expressions tend to be slow and other options + may be faster. + + +Example +======= + +In the following example it is checked if the msg object matches the regex string. + +.. code-block:: none + + re_match($msg,'(5[1-5][0-9]{14})') + + diff --git a/source/rainerscript/functions/rs-re_match_i.rst b/source/rainerscript/functions/rs-re_match_i.rst new file mode 100644 index 0000000..60d8cd2 --- /dev/null +++ b/source/rainerscript/functions/rs-re_match_i.rst @@ -0,0 +1,29 @@ +************ +re_match_i() +************ + +Purpose +======= + +re_match_i(expr, re) + +Returns 1, if expr matches re, 0 otherwise. Uses POSIX ERE. In contrast to +`re_match()` the matching is case-insensitive. + +.. note:: + + Functions using regular expressions tend to be slow and other options + may be faster. + + +Example +======= + +In the following example it is checked if the msg object matches the regex string. + +.. code-block:: none + + re_match($msg,'TesT') + +It matches it the message "Test", in any case ("TEST", "tEst", ...) +is contained in msg property. diff --git a/source/rainerscript/functions/rs-replace.rst b/source/rainerscript/functions/rs-replace.rst new file mode 100644 index 0000000..2d98e75 --- /dev/null +++ b/source/rainerscript/functions/rs-replace.rst @@ -0,0 +1,26 @@ +********* +replace() +********* + +Purpose +======= + +replace(str, substr_to_replace, replace_with) + +Returns new string with all instances of substr_to_replace replaced +by replace_with. + + +Example +======= + +.. code-block:: none + + replace("foo bar baz", " b", ", B") + +produces + +.. code-block:: none + + "foo, Bar, Baz" + diff --git a/source/rainerscript/functions/rs-script_error.rst b/source/rainerscript/functions/rs-script_error.rst new file mode 100644 index 0000000..88c5bff --- /dev/null +++ b/source/rainerscript/functions/rs-script_error.rst @@ -0,0 +1,30 @@ +************** +script_error() +************** + +Purpose +======= + +script_error() + +Returns the error state of functions that support it. C-Developers note that this +is similar to ``errno`` under Linux. The error state corresponds to the function +immediately called before. The next function call overrides it. + +Right now, the value 0 means that that the previous functions succeeded, any other +value that it failed. In the future, we may have more fine-grain error codes. + +Function descriptions mention if a function supports error state information. If not, +the function call will always set ``script_error()`` to 0. + + +Example +======= + +The following example shows that script_error() only needs to be called and does +not need any parameters. + +.. code-block:: none + + script_error() + diff --git a/source/rainerscript/functions/rs-strlen.rst b/source/rainerscript/functions/rs-strlen.rst new file mode 100644 index 0000000..569a955 --- /dev/null +++ b/source/rainerscript/functions/rs-strlen.rst @@ -0,0 +1,22 @@ +******** +strlen() +******** + +Purpose +======= + +strlen(str) + +Returns the length of the provided string. + + +Examples +======== + +In the following example returns the length of the message string. + +.. code-block:: none + + strlen($msg) + + diff --git a/source/rainerscript/functions/rs-substring.rst b/source/rainerscript/functions/rs-substring.rst new file mode 100644 index 0000000..b295abf --- /dev/null +++ b/source/rainerscript/functions/rs-substring.rst @@ -0,0 +1,75 @@ +*********** +substring() +*********** + +Purpose +======= + +`substring(str, start, subStringLength)` + +Creates a substring from `str`. The substring begins at `start` and is +at most `subStringLength` characters long. If `start` is higher than the +length of the string, the result will always be an empty string. The +same is the case if `subStringLength` is zero. + +.. note:: + + The first character of the string has the value 0. So if you set + start to '2', the substring will start with the third character. + +If you want to drop only some characters at the beginning of the string, +select an overlay large `subStringLength`, e.g. 1000000. As the length is +then always larger as any normal string, the function will return all but +the first part of the string. + +In order to aid removing `n` characters from the end of the string, you +can specify a **negative** `subStringLength`. This will result in an +actual `subStringLength` that is the string-length minus the specified +`subStringLength`. This is actually a shortcut for + +.. code-block:: none + + subStringLength = strlen(str) - n + +Specifying a negative `subStringLength` does not only offer a more +compact expression, it also has some performance benefits over the +use of `strlen()`. + + +Examples +======== + +In the following example a substring from the string is created, +starting with the 4th character and being 5 characters long. + +.. code-block:: none + + substring("123456789", 3, 5) + + +This example will result in the substring "45678". + +In the following example the first and the last character +of the string will be removed. + +.. code-block:: none + + substring("123456789", 1, -2) + + +This example will result in the substring "2345678". + +Note the `-2` value for `subStringLength`. As the extraction skips the +first character, you only need a substring of `strlen("123456789") - 2` +characters, as you want to remove the last character as well. In other +words: if you want to remove the first **and** last character from the +string, the substring in question is **two** characters shorter than the +original string! We know this is a bit counter-intuitive, this we +wanted to make you aware. + +As another example let us assume you want to drop the first two and the +last character. In this case you would use `subStringLength` of three: + +.. code-block:: none + + substring("123456789", 2, -3) diff --git a/source/rainerscript/functions/rs-tolower.rst b/source/rainerscript/functions/rs-tolower.rst new file mode 100644 index 0000000..904770e --- /dev/null +++ b/source/rainerscript/functions/rs-tolower.rst @@ -0,0 +1,22 @@ +********* +tolower() +********* + +Purpose +======= + +tolower(str) + +Converts the provided string into lowercase. + + +Example +======= + +The following example shows the syslogtag being converted to lower case. + +.. code-block:: none + + tolower($syslogtag) + + diff --git a/source/rainerscript/functions/rs-trim.rst b/source/rainerscript/functions/rs-trim.rst new file mode 100644 index 0000000..835b17b --- /dev/null +++ b/source/rainerscript/functions/rs-trim.rst @@ -0,0 +1,59 @@ +***************** +ltrim() / rtrim() +***************** + +Purpose +======= + +ltrim +----- + +ltrim(str) + +Removes any spaces at the start of a given string. Input is a string, output +is the same string starting with the first non-space character. + + +rtrim +----- + +rtrim(str) + +Removes any spaces at the end of a given string. Input is a string, output +is the same string ending with the last non-space character. + + +Example +======= + +ltrim +----- + +In the following example the spaces at the beginning of the string are removed. + +.. code-block:: none + + ltrim(" str ") + +produces + +.. code-block:: none + + "str " + + +rtrim +----- + +In the following example the spaces at the end of the string are removed. + +.. code-block:: none + + rtrim(" str ") + +produces + +.. code-block:: none + + " str" + diff --git a/source/rainerscript/functions/rs-wrap.rst b/source/rainerscript/functions/rs-wrap.rst new file mode 100644 index 0000000..d1dbd1c --- /dev/null +++ b/source/rainerscript/functions/rs-wrap.rst @@ -0,0 +1,51 @@ +****** +wrap() +****** + +Purpose +======= + +wrap(str, wrapper_str) +wrap(str, wrapper_str, escaper_str) + +Returns the str wrapped with wrapper_str. +In the second syntax additionally, any instances of wrapper_str appearing +in str would be replaced by the escaper_str. + + +Example +======= + +Syntax 1 +-------- + +The following example shows how the string is wrapped into +the wrapper_string. + +.. code-block:: none + + wrap("foo bar", "##") + +produces + +.. code-block:: none + + "##foo bar##" + + +Syntax 2 +-------- + +This example shows how parts of the string are being replaced. + +.. code-block:: none + + wrap("foo'bar", "'", "_") + +produces + +.. code-block:: none + + "'foo_bar'" + + diff --git a/source/rainerscript/global.rst b/source/rainerscript/global.rst new file mode 100644 index 0000000..a55f54a --- /dev/null +++ b/source/rainerscript/global.rst @@ -0,0 +1,811 @@ +global() configuration object +============================= + +The global configuration object permits to set global parameters. Note +that each parameter can only be set once and cannot be re-set +thereafter. If a parameter is set multiple times, the behaviour is +unpredictable. As with other configuration objects, parameters for this +object are case-insensitive. + +The following parameters can be set: + +- **action.reportSuspension** - binary, default "on", v7.5.8+ + + If enabled ("on") action will log message under `*syslog.\**` when an + action suspends or resumes itself. This usually happens when there are + problems connecting to backend systems. If disabled ("off"), these + messages are not generated. These messages can be useful in detecting + problems with backend systems. Most importantly, frequent suspension + and resumption points to a problem area. + +- **action.reportSuspensionContinuation** - binary, default "off", v7.6.1+, v8.2.0+ + + If enabled ("on") the action will not only report the first suspension but + each time the suspension is prolonged. Otherwise, the follow-up messages + are not logged. If this setting is set to "on", action.reportSuspension is + also automatically turned "on". + +- **workDirectory** + + Sets the directory that rsyslog uses for work files, e.g. imfile state + or queue spool files. + +- **umask** available 8.26.0+ + + Sets the rsyslogd process' umask. If not specified, the system-provided default + is used. The value given must always be a 4-digit octal number, with the initial + digit being zero. + +- **dropMsgsWithMaliciousDNSPtrRecords** + +- **localHostname** + Permits to overwrite the local host hostname. + +- **preserveFQDN** +- **defaultNetstreamDriverCAFile** + + For `TLS syslog <http://www.rsyslog.com/doc/rsyslog_secure_tls.html>`_, + the CA certificate that can verify the machine keys and certs (see below) + +- **defaultNetstreamDriverCRLFile** + + For `TLS syslog <http://www.rsyslog.com/doc/rsyslog_secure_tls.html>`_, + the CRL File contains a List contains a list of revoked certrificates. + +- **defaultNetstreamDriverKeyFile** + + Machine private key + +- **defaultNetstreamDriverCertFile** + + Machine public key (certificate) + +- **debug.gnutls** (0-10; default:0) + + Any other parameter than 0 enables the debug messages of GnuTLS. The + amount of messages given depends on the height of the parameter, 0 + being nothing and 10 being very much. Caution! higher parameters may + give out way more information than needed. We advise you to first use + small parameters to prevent that from happening. + **This parameter only has an effect if general debugging is enabled.** + +- **netstreamDriverCaExtraFiles** + + This directive allows to configure multiple additional extra CA files. + This is intended for SSL certificate chains to work appropriately, + as the different CA files in the chain need to be specified. + It must be remarked that this parameter only works with the OpenSSL driver. + +- **processInternalMessages** binary (on/off) + + This tells rsyslog if it shall process internal messages itself. The + default mode of operations ("off") makes rsyslog send messages to the + system log sink (and if it is the only instance, receive them back from there). + This also works with systemd journal and will make rsyslog messages show up in the + systemd status control information. + + If this (instance) of rsyslog is not the main instance and there is another + main logging system, rsyslog internal messages will be inserted into + the main instance's syslog stream. In this case, setting to ("on") will + let you receive the internal messages in the instance they originate from. + + Note that earlier versions of rsyslog worked the opposite way. More + information about the change can be found in `rsyslog-error-reporting-improved <http://www.rsyslog.com/rsyslog-error-reporting-improved>`_. + + + +- **stdlog.channelspec** + + Permits to set the liblogging-stdlog channel specifier string. This + in turn permits to send rsyslog log messages to a destination different + from the system default. Note that this parameter has only effect if + *processInternalMessages* is set to "off". Otherwise it is silently + ignored. + +- **shutdown.enable.ctlc** + + If set to "on", rsyslogd can be terminated by pressing ctl-c. This is + most useful for containers. If set to "off" (the default), this is not + possible. + +- **defaultNetstreamDriver** + + Set it to "ossl" or "gtls" to enable TLS. + This `guide <http://www.rsyslog.com/doc/rsyslog_secure_tls.html>`_ + shows how to use TLS. + +- **maxMessageSize** + + Configures the maximum message size allowed for all inputs. Default is 8K. + Anything above the maximum size will be truncated. + + Note: some modules provide separate parameters that allow overriding this + setting (e.g., :doc:`imrelp's MaxDataSize parameter <../../configuration/modules/imrelp>`). + +.. _global_janitorInterval: + +- **janitor.interval** [minutes], available 8.3.3+ + + Sets the interval at which the + :doc:`janitor process <../concepts/janitor>` + runs. + +- **debug.onShutdown** available 7.5.8+ + + If enabled ("on"), rsyslog will log debug messages when a system + shutdown is requested. This can be used to track issues that happen + only during shutdown. During normal operations, system performance is + NOT affected. + Note that for this option to be useful, the debug.logFile parameter + must also be set (or the respective environment variable). + +- **debug.logFile** available 7.5.8+ + + This is used to specify the debug log file name. It is used for all + debug output. Please note that the RSYSLOG\_DEBUGLOG environment + variable always **overrides** the value of debug.logFile. + +- **net.ipprotocol** available 8.6.0+ + + This permits to instruct rsyslog to use IPv4 or IPv6 only. Possible + values are "unspecified", in which case both protocols are used, + "ipv4-only", and "ipv6-only", which restrict usage to the specified + protocol. The default is "unspecified". + + Note: this replaces the former *-4* and *-6* rsyslogd command line + options. + +- **net.aclAddHostnameOnFail** available 8.6.0+ + + If "on", during ACL processing, hostnames are resolved to IP addresses for + performance reasons. If DNS fails during that process, the hostname + is added as wildcard text, which results in proper, but somewhat + slower operation once DNS is up again. + + The default is "off". + +- **net.aclResolveHostname** available 8.6.0+ + + If "off", do not resolve hostnames to IP addresses during ACL processing. + + The default is "on". + +- **net.enableDNS** [on/off] available 8.6.0+ + + **Default:** on + + Can be used to turn DNS name resolution on or off. + +- **net.permitACLWarning** [on/off] available 8.6.0+ + + **Default:** on + + If "off", suppress warnings issued when messages are received + from non-authorized machines (those, that are in no AllowedSender list). + +- **parser.parseHostnameAndTag** [on/off] available 8.6.0+ + + **Default:** on + + This controls whether the parsers try to parse HOSTNAME and TAG fields + from messages. The default is "on", in which case parsing occurs. If + set to "off", the fields are not parsed. Note that this usually is + **not** what you want to have. + + It is highly suggested to change this setting to "off" only if you + know exactly why you are doing this. + +- **parser.permitSlashInProgramName** [on/off] available 8.25.0+ + + **Default:** off + + This controls whether slashes in the "programname" property + (the static part of the tag) are permitted or not. By default + this is not permitted, but some Linux tools (including most + importantly the journal) store slashes as part of the program + name inside the syslogtag. In those cases, the ``programname`` + is truncated at the first slash. + + In other words, if the setting is off, a value of ``app/foo[1234]`` + in the tag will result in a programname of ``app``, and if an + application stores an absolute path name like ``/app/foo[1234]``, + the ``programname`` property will be empty (""). + If set to ``on``, a syslogtag of ``/app/foo[1234]`` will result + in a ``programname`` value of ``/app/foo`` and a syslogtag of + ``app/foo[1234]`` will result in a ``programname`` value of + ``app/foo``. + +- **parser.escapeControlCharacterTab** [on/off] available since 8.7.0 + + **Default:** on + + If set to "off", the TAB control character (US-ASCII HT) will not be + escaped. If set to "on", it will be escaped to the sequence "#011". + Note that escaping is the traditional behavior and existing scripts + may get into trouble if this is changed to "off". + +- **parser.controlCharacterEscapePrefix** [char] + + **Default:** '#' + + This option specifies the prefix character to be used for control + character escaping (see option + *parser.escapeControlCharactersOnReceive*). + +- **parser.escape8BitCharactersOnReceive** [on/off] + + **Default:** off + + This parameter instructs rsyslogd to replace non US-ASCII characters + (those that have the 8th bit set) during reception of the message. + This may be useful for some systems. Please note that this escaping + breaks Unicode and many other encodings. Most importantly, it can be + assumed that Asian and European characters will be rendered hardly + readable by this settings. However, it may still be useful when the + logs themselves are primarily in English and only occasionally contain + local script. If this option is turned on, all control-characters are + converted to a 3-digit octal number and be prefixed with the + *parser.controlCharacterEscapePrefix* character (being '#' by default). + + **Warning:** + + - turning on this option most probably destroys non-western character + sets (like Japanese, Chinese and Korean) as well as European + character sets. + - turning on this option destroys digital signatures if such exists + inside the message + - if turned on, the drop-cc, space-cc and escape-cc `property + replacer <property_replacer.html>`_ options do not work as expected + because control characters are already removed upon message + reception. If you intend to use these property replacer options, you + must turn off *parser.escape8BitCharactersOnReceive*. + +- **parser.escapeControlCharactersOnReceive** [on/off] + + **Default:** on + + This parameter instructs rsyslogd to replace control characters during + reception of the message. The intent is to provide a way to stop + non-printable messages from entering the syslog system as whole. If this + option is turned on, all control-characters are converted to a 3-digit + octal number and be prefixed with the *parser.controlCharacterEscapePrefix* + character (being '#' by default). For example, if the BEL character + (ctrl-g) is included in the message, it would be converted to '#007'. + To be compatible to sysklogd, this option must be turned on. + + **Warning:** + + - turning on this option most probably destroys non-western character + sets (like Japanese, Chinese and Korean) + - turning on this option destroys digital signatures if such exists + inside the message + - if turned on, the drop-cc, space-cc and escape-cc `property + replacer <property_replacer.html>`_ options do not work as expected + because control characters are already removed upon message + reception. If you intend to use these property replacer options, you + must turn off *parser.escapeControlCharactersOnReceive*. + + +- **senders.keepTrack** [on/off] available 8.17.0+ + + **Default:** off + + If turned on, rsyslog keeps track of known senders and also reports + statistical data for them via the impstats mechanism. + + A list of active senders is kept. When a new sender is detected, an + informational message is emitted. Senders are purged from the list + only after a timeout (see *senders.timeoutAfter* parameter). Note + that we do not intentionally remove a sender when a connection is + closed. The whole point of this sender-tracking is to have the ability + to provide longer-duration data. As such, we would not like to drop + information just because the sender has disconnected for a short period + of time (e.g. for a reboot). + + Senders are tracked by their hostname (taken at connection establishment). + + Note: currently only imptcp and imtcp support sender tracking. + +- **senders.timeoutAfter** [seconds] available 8.17.0+ + + **Default:** 12 hours (12*60*60 seconds) + + Specifies after which period a sender is considered to "have gone + away". For each sender, rsyslog keeps track of the time it least + received messages from it. When it has not received a message during + that interval, rsyslog considers the sender to be no longer present. + It will then a) emit a warning message (if configured) and b) purge + it from the active senders list. As such, the sender will no longer + be reported in impstats data once it has timed out. + +- **senders.reportGoneAway** [on/off] available 8.17.0+ + + **Default:** off + + Emit a warning message when now data has been received from a sender + within the *senders.timeoutAfter* interval. + +- **senders.reportNew** [on/off] available 8.17.0+ + + **Default:** off + + If sender tracking is active, report a sender that is not yet inside + the cache. Note that this means that senders which have been timed out + due to prolonged inactivity are also reported once they connect again. + +- **debug.unloadModules** [on/off] available 8.17.0+ + + **Default:** on + + This is primarily a debug setting. If set to "off", rsyslog will never + unload any modules (including plugins). This usually causes no operational + problems, but may in extreme cases. The core benefit of this setting is + that it makes valgrind stack traces readable. In previous versions, the + same functionality was only available via a special build option. + +- **debug.files** [ARRAY of filenames] available 8.29.0+ + + **Default:** none + + This can be used to configure rsyslog to only show debug-output generated in + certain files. If the option is set, but no filename is given, the + debug-output will behave as if the option is turned off. + + Do note however that due to the way the configuration works, this might not + effect the first few debug-outputs, while rsyslog is reading in the configuration. + For optimal results we recommend to put this parameter at the very start of + your configuration to minimize unwanted output. + + See debug.whitelist for more information. + +- **debug.whitelist** [on/off] available 8.29.0+ + + **Default:** on + + This parameter is an assisting parameter of debug.files. If debug.files + is used in the configuration, debug.whitelist is a switch for the files named + to be either white- or blacklisted from displaying debug-output. If it is set to + on, the listed files will generate debug-output, but no other files will. + The reverse principle applies if the parameter is set to off. + + See debug.files for more information. + +- **environment** [ARRAY of environment variable=value strings] available 8.23.0+ + + **Default:** none + + This permits to set environment variables via rsyslog.conf. The prime + motivation for having this is that for many libraries, defaults can be + set via environment variables, **but** setting them via operating system + service startup files is cumbersome and different on different platforms. + So the *environment* parameter provides a handy way to set those + variables. + + A common example is to set the *http_proxy* variable, e.g. for use with + KSI signing or ElasticSearch. This can be done as follows:: + + global(environment="http_proxy=http://myproxy.example.net") + + Note that an environment variable set this way must contain an equal sign, + and the variable name must not be longer than 127 characters. + + It is possible to set multiple environment variables in a single + global statement. This is done in regular array syntax as follows:: + + global(environment=["http_proxy=http://myproxy.example.net", + "another_one=this string is=ok!"] + ) + + As usual, whitespace is irrelevant in regard to parameter placing. So + the above sample could also have been written on a single line. + +- **internalmsg.ratelimit.interval** [positive integer] available 8.29.0+ + + **Default:** 5 + + Specifies the interval in seconds onto which rate-limiting is to be + applied to internal messages generated by rsyslog(i.e. error messages). + If more than internalmsg.ratelimit.burst messages are read during + that interval, further messages up to the end of the interval are + discarded. + +- **internalmsg.ratelimit.burst** [positive integer] available 8.29.0+ + + **Default:** 500 + + Specifies the maximum number of internal messages that can be emitted within + the ratelimit.interval interval. For further information, see + description there. + + + **Caution:** Environment variables are set immediately when the + corresponding statement is encountered. Likewise, modules are loaded when + the module load statement is encountered. This may create **sequence + dependencies** inside rsyslog.conf. To avoid this, it is highly suggested + that environment variables are set **right at the top of rsyslog.conf**. + Also, rsyslog-related environment variables may not apply even when set + right at the top. It is safest to still set them in operating system + start files. Note that rsyslog environment variables are usually intended + only for developers so there should hardly be a need to set them for a + regular user. Also, many settings (e.g. debug) are also available as + configuration objects. + +- **internalmsg.severity** [syslog severity value] available 8.1905.0+ + + **Default:** info + + This permits to limit which internal messages are emitted by rsyslog. This + is especially useful if internal messages are reported to systemd journal, + which is the default on journal systems. In that case there is no other + ability to filter out messages before they are logged by the journal. + + While any syslog severity value can be used, the most useful ones are + + * `error`, to see only error messages but ignore anything else + * `warn`, to also see warning messages (highly recommended) + * `info`, to also see informational messages like events generated + by DA queues status checks. This is the default as the informational + messages often provide valuable information. + * `debug`, to see all messages, including only those interesting for + debugging. While this is still considerably lower volume than a + rsyslog developer debug log, this can be quite verbose. Selecting + `debug` without hard need thus is **not** recommended. + + We expect that users are most often interested in limiting verboseness + to warning messages. This can be done e.g. via:: + + global(internalmsg.severity="warn") + +- **errorMessagesToStderr.maxNumber** [positive integer] available 8.30.0+ + + **Default:** unlimited + + This permits to put a hard limit on the number of messages that can + go to stderr. If for nothing else, this capability is helpful for the + testbench. It permits to reduce spamming the test log while still + providing the ability to see initial error messages. Might also be + useful for some practical deployments. + +- **variables.caseSensitive** [boolean (on/off)] available 8.30.0+ + + **Default:** off + + This permits to make variables case-sensitive, what might be required + for some exotic input data where case is the only difference in + field names. Note that in rsyslog versions prior to 8.30, the default was + "on", which very often led to user confusion. There normally should be no + need to switch it back to "on", except for the case to be mentioned. + This is also the reason why we switched the default. + +- **internal.developeronly.options** + + This is NOT to be used by end users. It provides rsyslog developers the + ability to do some (possibly strange) things inside rsyslog, e.g. for + testing. This parameter should never be set, except if instructed by + a developer. If it is set, rsyslog may misbehave, segfault, or cause + other strange things. Note that option values are not guaranteed to + stay the same between releases, so do not be "smart" and apply settings + that you found via a web search. + + Once again: **users must NOT set this parameter!** + +- **oversizemsg.errorfile** [file name] available 8.35.0+ + + This parameter is used to specify the name of the oversize message log file. + Here messages that are longer than maxMessageSize will be gathered. + +- **oversizemsg.input.mode** [mode] available 8.35.0+ + + With this parameter the behavior for oversized messages can be specified. + Available modes are: + + - truncate: Oversized messages will be truncated. + - split: Oversized messages will be split and the rest of the message will + be sent in another message. + - accept: Oversized messages will still be accepted. + +- **oversizemsg.report** [boolean (on/off)] available 8.35.0+ + + This parameter specifies if an error shall be reported when an oversized + message is seen. The default is "on". + +- **abortOnUncleanConfig** [boolean (on/off)] available 8.37.0+ + + This parameter permits to prevent rsyslog from running when the + configuration file is not clean. "Not Clean" means there are errors or + some other annoyances that rsyslogd reports on startup. This is a + user-requested feature to have a strict startup mode. Note that with the + current code base it is not always possible to differentiate between an + real error and a warning-like condition. As such, the startup will also + prevented if warnings are present. I consider this a good thing in being + "strict", but I admit there also currently is no other way of doing it. + +- **abortOnFailedQueueStartup** [boolean (on/off)] available 8.2210.0+ + + This parameter is similiar to *abortOnUncleanConfig* but makes rsyslog + abort when there are any problems with queue startup. This is usually + caused by disk queue settings or disk queue file corruption. Normally, + rsyslog ignores disk queue definitions in this case and switches the + queue to emergency mode, which permits in-memory operations. This is + desired by the fast majority of users, because it permits rsyslog to + remain operational and process all remaining actions as well as handle + actions associated with the failed queue decently. + When this setting is "on", rsyslog aborts immediately when a queue + problem is detected during startup. If you use this mode, ensure that + your startup scripts monitor for these type of errors and handle them + appropriately. + In our opinion, it is much safer to let rsyslog start and monitor queue + error messages. + + The **default** for this setting is "off" + +- **inputs.timeout.shutdown** [numeric, ms] available 8.37.0+ + + This parameter specifies how long input modules are given time to terminate + when rsyslog is shutdown. The default is 1000ms (1 second). If the input + requires longer to terminate, it will be cancelled. This is necessary if + the input is inside a lengthy operation, but should generally be tried to + avoid. On busy systems it may make sense to increase that timeout. This + especially seems to be the case with containers. + +- **default.action.queue.timeoutshutdown** [numeric] available 8.1901.0+ +- **default.action.queue.timeoutactioncompletion** [numeric] available 8.1901.0+ +- **default.action.queue.timeoutenqueue** [numeric] available 8.1901.0+ +- **default.action.queue.timeoutworkerthreadshutdown** [numeric] available 8.1901.0+ + + These parameters set global queue defaults for the respective queue settings. + +- **reverselookup.cache.ttl.default** [numeric, seconds] available 8.1904.0+ + + Rsyslog includes a cache for ip-address-to-hostname lookups. This is most + useful for inputs without a connection. imudp is the prime example. + This settings permits to specify after which period (in seconds) an + entry expires. Upon expiration the entry will be discarded and re-queried. + The **default** value is 24 hours. + To never cache entries, set the parameter to 0, which will make cache + entries expire immediately. Note that especially with imudp this can + cause huge performance degradation and potentially also message loss. + + Note: for many years rsyslog did **not** timeout cache entries at all. This + only occasionally caused issues. We assume that the once-every-24-hrs + default value is a very good compromise between performance and + keeping reverse lookup information current. + +- **reverselookup.cache.ttl.enable** [boolean (on/off)] available 8.1904.0+ + + This configures whether rsyslog expires DNS cache entries (setting "on") or + not (setting "off", the default). If configured to "off", + *reverselookup.cache.default.ttl* is not in effect. Note that this is the + **default**. + +- **security.abortOnIDResolutionFail** [boolean (on/off)], default "on", available 8.2002.0+ + + This setting controls if rsyslog should error-terminate when an security ID cannot + be resolved during config file processing at startup. If set to "on" and + a name ID lookup fails (for user and group names) rsyslog does not start but + terminate with an error message. This is necessary as a security + measure, as otherwise the wrong permissions can be assigned or privileges + are not dropped. This setting is applied whereever security IDs are resolved, + e.g. when dropping privileges or assigning file permissions or owners. + + The setting should be at the top of the configuration parameters to make sure its + behavior is correctly applied on all other configuration parameters. + + **CHANGE OF BEHAVIOR** + + The default for this parameter is "on". In versions prior to 8.2002.0, the default + was "off" (by virtue of this parameter not existing). As such, existing + configurations may now error out. + + We have decided to accept this change of behavior because of the potential + security implications. + +- **operatingStateFile** [string, filename], default unset, available 8.39.0+ + + The operatingStateFile, as the name says, provides information about rsyslog + operating state. It can be useful for troubleshooting. + + If this parameter is not set, an operating state file will not be written. If + it is set, the file will be written **and** used to detect unclean shutdown. + Upon startup, rsyslog checks if the last recorded line contains the "clean + shutdown notification". If so, the file is deleted and re-written with new + operating state. If the notification cannot be found, rsyslog assumes unclean + shutdown and complains about this state. In this case the operating state file + is renamed to "<configured-name>.previous" and a new file is started under the + configured name for the current run. This permits the administrator to check the + previous operating state file for helpful information on why the system shut + down unclean. + +- **reportChildProcessExits** [none|errors|all], default "errors", available + 8.1901.0+ + + Tells rsyslog whether and when to log a message (under *syslog.\**) when a + child process terminates. The available modes are: + + - none: Do not report any child process termination. + - errors: Only report the termination of child processes that have exited with + a non-zero exit code, or that have been terminated by a signal. + - all: Report all child process terminations. + + The logged message will be one of the following: + + - "program 'x' (pid n) exited with status s" (with "info" severity if the + status is zero, and "warning" severity otherwise) + - "program 'x' (pid n) terminated by signal s" (with "warning" severity) + + In some cases, the program name is not included in the message (but only the PID). + + Normally, if a child process terminates prematurely for some reason, rsyslog will + also report some specific error message the next time it interacts with the process + (for example, in the case of a process started by omprog, if omprog cannot send a + message to the process because the pipe is broken, it will report an error + indicating this). This specific error message (if any) is not affected by this + global setting. + + +- **default.ruleset.queue.timeoutshutdown** +- **default.ruleset.queue.timeoutactioncompletion** +- **default.ruleset.queue.timeoutenqueue** +- **default.ruleset.queue.timeoutworkerthreadshutdown** + + Sets default parameters for ruleset queues. See queue doc for the meaning of + the individual settings. + + +- **default.action.queue.timeoutshutdown** +- **default.action.queue.timeoutactioncompletion** +- **default.action.queue.timeoutenqueue** +- **default.action.queue.timeoutworkerthreadshutdown** + + Sets default parameters for action queues. See queue doc for the meaning of + the individual settings. + + +- **shutdown.queue.doublesize** + + This setting (default "off") permits to temporarily increase the maximum queue + size during shutdown processing. This is useful when rsyslog needs to re-enqueue + some messages at shutdown *and* the queue is already full. Note that the need to + re-enqueue messages stems back to some failed operations. Note that the maximum + permitted queue size is doubled, as this ensures in all cases that re-enqueuing + can be completed. Note also that the increase of the max size is temporary during + shutdown and also does not requiere any more storage. Except, of course, for + re-enqueued message. + + The situation addressed by this setting is unlikely to happen, but it could happen. + To enable the funtionality, set it to "on". + +- **parser.supportCompressionExtension** [boolean (on/off)] available 8.2106.0+ + + This parameter permits to disable rsyslog's single-message-compression extension on + reception ("off"). The default is to keep it activated ("on"). + + The single-message-compression extension permits senders to zip-compress single + syslog messages. Such messages start with the letter "z" instead of the usual + syslog PRI value. For well-formed syslog messages, the extension works as designed. + However, some users transport non-syslog data via rsyslog, and such messages may + validly start with "z" for non-compressed data. To support such non-standard + cases, this option can be used to globally disable support for compression on + all inputs. + +privdrop.group.name +^^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "", "no", "``$PrivDropToGroup``" + +.. versionadded:: 8.2110.0 + +Name of the group rsyslog should run under after startup. Please +note that this group is looked up in the system tables. If the lookup +fails, privileges are NOT dropped. Thus it is advisable to use the +less convenient `privdrop.group.id` parameter. Note that all +supplementary groups are removed by default from the process if the +`privdrop.group.keepsupplemental` parameter is not specified. +If the group id can be looked up, but can not be set, +rsyslog aborts. + +Note: See the :doc:`privilege drop documentation<../configuration/droppriv>` +for more details on dropping privileges on startup. + +privdrop.group.id +^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "", "no", "``$PrivDropToGroupID``" + +.. versionadded:: 8.2110.0 + +Numerical user ID of the group rsyslog should run under after startup. +This is more reliable than the `privdrop.group.name` parameter, which +relies on presence of the group name in system tables. The change to +the ID will always happen if the ID is valid. + +Note: See the :doc:`privilege drop documentation<../configuration/droppriv>` +for more details on dropping privileges on startup. + +privdrop.user.name +^^^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "", "no", "``$PrivDropToUser``" + +.. versionadded:: 8.2110.0 + + +Name of the user rsyslog should run under after startup. Please note +that this user is looked up in the system tables. If the lookup +fails, privileges are NOT dropped. Thus it is advisable to use the +less convenient `privdrop.user.id` parameter. If the user id can be +looked up, but can not be set, rsyslog aborts. + +Note: See the :doc:`privilege drop documentation<../configuration/droppriv>` +for more details on dropping privileges on startup. + +privdrop.user.id +^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "", "no", "``$PrivDropToUserID``" + +.. versionadded:: 8.2110.0 + +Numerical user ID of the user rsyslog should run under after startup. +This is more reliable than the `privdrop.user.name` parameter, which +relies on presence of the user name in system tables. The change to +the ID will always happen if the ID is valid. + +Note: See the :doc:`privilege drop documentation<../configuration/droppriv>` +for more details on dropping privileges on startup. + +libcapng.default +^^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "on", "no", "none" + +.. versionadded:: 8.2306.0 + +The `libcapng.default` global option defines how rsyslog should behave +in case something went wrong when capabilities were to be dropped. +The default value is "on", in which case rsyslog exits on a libcapng +related error. If set to "off", an error message describing the problem +appears at startup, nothing more. Default value is preserved for backwards +compatibility. + +libcapng.enable +^^^^^^^^^^^^^^^ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "on", "no", "none" + +.. versionadded:: 8.2310.0 + +The `libcapng.enable` global option defines whether rsyslog should +drop capabilities at startup or not. By default, it is set to "on". +Until this point, if the project was compiled with --enable-libcap-ng option, +capabilities were automatically dropped. This is configurable now. diff --git a/source/rainerscript/include.rst b/source/rainerscript/include.rst new file mode 100644 index 0000000..f2a01c2 --- /dev/null +++ b/source/rainerscript/include.rst @@ -0,0 +1,153 @@ +**************************** +The rsyslog include() object +**************************** + +The ``include()`` object is used to include configuration snippets +stored elsewhere into the configuration. + +.. versionadded:: 8.33.0 + +.. note:: + + This configuration option deprecates the older ``$IncludeConfig`` + |FmtObsoleteName| format directive. + +How it Works +============ + +The rsyslog include object is modelled after the usual "include" directive +in programming and script languages (e.g. \#include in C). + +If you are not familiar with this, compare it to copy and paste: whenever +rsyslog finds an include object, in copies the text from that include file +at the exact position where the include is specified and removes the include +text. + +Now remember that rsyslog's configuration statements are depending on the +position inside the configuration. It is important if a statement occurs +before or after another one. This is similar how other configuration files +work and also the same concept that almost all programming and script +languages have. + +If you use includes in rsyslog, you must think about the position at which +the include text is inserted. This is especially important if you use +statements like `stop`. If given at the wrong spot, they will not work as +intended. + +If in doubt, or if you have issues, it probably is best NOT to use includes. +This makes it far more obvious to understand what happens. Once solved, you +may then change back to includes again. + + +Parameters +========== + +.. note:: + + Parameter names are case-insensitive. + +.. warning:: + + Only one of the ``file`` or ``text`` parameters may be specified for each + ``include()`` object. + + +file +---- + +Name of file to be included. May include wildcards, in which case all +matching files are included (in order of file name sort order). + + +text +---- + +Text to be included. This is most useful when using backtick string +constants. + + +mode +---- + +Affects how missing files are to be handled: + +- ``abort-if-missing``, with rsyslog aborting when the file is not present +- ``required`` *(default)*, with rsyslog emitting an error message but otherwise + continuing when the file is not present +- ``optional``, which means non-present files will be skipped without notice + +Examples +======== + +Include a required file +----------------------- + +.. code-block:: none + + include(file="/path/to/include.conf") + +.. note:: + + Unless otherwise specified, files referenced by an ``include()`` object + must be present, otherwise an error will be generated. + + +Include an optional file +------------------------ + +The referenced file will be used if found, otherwise no errors or warnings +will be generated regarding its absence. + +.. code-block:: none + :emphasize-lines: 3 + + include( + file="/path/to/include.conf" + mode="optional" + ) + + +Include multiple files +---------------------- + +.. code-block:: none + + include(file="/etc/rsyslog.d/*.conf") + +.. note:: + + Unless otherwise specified, files referenced by an ``include()`` object + must be present, otherwise an error will be generated. + + +Include an environment variable as configuration +------------------------------------------------ + +.. code-block:: none + + include(text=`echo $ENV_VAR`) + + +Include a file specified via an environment variable +---------------------------------------------------- + +.. code-block:: none + + include(file=`echo $ENV_VAR`) + +.. note:: + + Unless otherwise specified, files referenced by an ``include()`` object + must be present, otherwise an error will be generated. + + +Include an optional file specified via an environment variable +-------------------------------------------------------------- + +.. code-block:: none + :emphasize-lines: 3 + + include( + file=`echo $ENV_VAR` + mode="optional" + ) diff --git a/source/rainerscript/index.rst b/source/rainerscript/index.rst new file mode 100644 index 0000000..4b277f7 --- /dev/null +++ b/source/rainerscript/index.rst @@ -0,0 +1,30 @@ +RainerScript +============ + +**RainerScript is a scripting language specifically designed and +well-suited for processing network events and configuring event +processors.** +It is the prime configuration language used for rsyslog. +Please note that RainerScript may not be abbreviated as rscript, +because that's somebody else's trademark. + +Some limited RainerScript support is available since rsyslog 3.12.0 +(for expression support). In v5, "if .. then" statements are supported. +The first full implementation is available since rsyslog v6. + +.. toctree:: + :maxdepth: 2 + + data_types + expressions + functions/index + control_structures + configuration_objects + constant_strings + variable_property_types + lookup_tables + queue_parameters + rainerscript_call + rainerscript_call_indirect + global + include diff --git a/source/rainerscript/lookup_tables.rst b/source/rainerscript/lookup_tables.rst new file mode 100644 index 0000000..29178d3 --- /dev/null +++ b/source/rainerscript/lookup_tables.rst @@ -0,0 +1,7 @@ +Lookup Tables +============= + +:doc:`Lookup tables <../configuration/lookup_tables>` are a powerful construct to obtain +"class" information based on message content (e.g. to build log file +names for different server types, departments or remote offices). + diff --git a/source/rainerscript/queue_parameters.rst b/source/rainerscript/queue_parameters.rst new file mode 100644 index 0000000..19e850c --- /dev/null +++ b/source/rainerscript/queue_parameters.rst @@ -0,0 +1,607 @@ +************************ +General Queue Parameters +************************ + +=========================== =========================================================================== +**Authors:** `Rainer Gerhards <https://rainer.gerhards.net/>`_ <rgerhards@adiscon.com>; +=========================== =========================================================================== + + +Usage +===== + +Queue parameters can be used together with the following statements: + +- :doc:`action() <../configuration/actions>` +- ruleset() +- main\_queue() + +Queues need to be configured in the action or ruleset it should affect. +If nothing is configured, default values will be used. Thus, the default +ruleset has only the default main queue. Specific Action queues are not +set up by default. + +To fully understand queue parameters and how they interact, be sure to +read the :doc:`queues <../concepts/queues>` documentation. + + +Configuration Parameters +======================== + +.. note:: + + As with other configuration objects, parameters for this + object are case-insensitive. + + +queue.filename +-------------- + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "``$ActionQueueFileName``" + +File name to be used for the queue files. If specified, this parameter +enables disk-assisted queue functionality. If *not* specified, +the queue will operate without saving the queue to disk, either +during its operation or when shut down. See the separate +``queue.saveonshutdown`` parameter to configure that option. +Please note that this is actually just the file name. A directory +can NOT be specified in this parameter. If the files shall be +created in a specific directory, specify ``queue.spoolDirectory`` +for this. The filename is used to build to complete path for queue +files. + + +queue.spoolDirectory +-------------------- + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "none", "no", "none" + +This is the directory into which queue files will be stored. Note +that the directory must exist, it is NOT automatically created by +rsyslog. If no spoolDirectory is specified, the work directory is +used. + + +queue.size +---------- + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "1000/50000", "no", "``$ActionQueueSize``" + +This is the maximum size of the queue in number of messages. Note +that setting the queue size to very small values (roughly below 100 +messages) is not supported and can lead to unpredictable results. +For more information on the current status of this restriction see +the `rsyslog FAQ: "lower bound for queue +sizes" <http://www.rsyslog.com/lower-bound-for-queue-sizes/>`_. + +The default depends on queue type and rsyslog version, if you need +a specific value, please specify it. Otherwise rsyslog selects what +it considers appropriate for the version in question. In rsyslog +rsyslog 8.30.0, for example, ruleset queues have a default size +of 50000 and action queues which are configured to be non-direct +have a size of 1000. + + +queue.dequeueBatchSize +---------------------- + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "128/1024", "no", "``$ActionQueueDequeueBatchSize``" + +Specifies the maximum batch size for dequeue operations. This setting affects performance. +As a rule of thumb, larger batch sizes (up to a environment-induced upper limit) +provide better performance. For the average system, there usually should be no need +to adjust batch sizes as the defaults are sufficient. The default for ruleset queues +is 1024 and for action queues 128. + +Note that this only specifies the **maximum** batch size. Batches will be slower if +rsyslog does not have as many messages inside the queue at time of dequeuing it. +If you want to set a minimum Batch size as well, you can use `queue.minDequeueBatchSize`. + + +queue.minDequeueBatchSize +------------------------- + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "none" + +Specifies the **minimum** batch size for dequeue operations. This setting is especially +useful with outputs like ElasticSearch or ClickHouse, where you want to limit the +number of HTTP requests. With this setting, the queue engine waits up to +`queue.minDequeueBatchSize.timeout` milliseconds when there are fewer messages +currently queued. Note that the minimum batch size cannot be larger than the +configured maximum batch size. If so, it is automatically adjusted to +match the maximum. So if in doubt, you need to specify both parameters. + + +queue.minDequeueBatchSize.timeout +--------------------------------- + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "1000", "no", "none" + +This parameter is only meaningful if use together with `queue.minDequeueBatchSize`, +otherwise it is ignored. It specifies the amount of time (in milliseconds) rsyslogs +waits for new +messages so that the minimum batch size can be reached. After this period, the +batch is processed, *even if it is below minimum size*. This capability exists to +prevent having messages stalled in an incomplete batch just because no new +messages arrive. We would expect that it usually makes little sense to set it +to higher than 60.000 (60 seconds), but this is permitted. Just be warned that +this potentially delays log processing for that long. + + +queue.maxDiskSpace +------------------ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "``$ActionQueueMaxDiskSpace``" + +The maximum size that all queue files together will use on disk. Note +that the actual size may be slightly larger than the configured max, +as rsyslog never writes partial queue records. + + +queue.highWatermark +------------------- + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "90% of queue.size", "no", "``$ActionQueueHighWaterMark``" + +This applies to disk-assisted queues, only. When the queue fills up +to this number of messages, the queue begins to spool messages to +disk. Please note that this should not happen as part of usual +processing, because disk queue mode is very considerably slower than +in-memory queue mode. Going to disk should be reserved for cases +where an output action destination is offline for some period. + + +queue.lowWatermark +------------------ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "70% of queue.size", "no", "``$ActionQueueLowWaterMark``" + +This applies to disk-assisted queues, only. When the high watermark is +reached, the queue will write data to disk. It does so until the low +watermark is reached, then the queue reverts back to in-memory mode. + + +queue.fullDelaymark +------------------- + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "97% of queue.size", "no", "none" + +Number of messages when the queue should block delayable messages. +Messages are NO LONGER PROCESSED until the queue has sufficient space +again. If a message is delayable depends on the input. For example, +messages received via imtcp are delayable (because TCP can push back), +but those received via imudp are not (as UDP does not permit a push back). +The intent behind this setting is to leave some space in an almost-full +queue for non-delayable messages, which would be lost if the queue runs +out of space. Please note that if you use a DA queue, setting the +fulldelaymark BELOW the highwatermark makes the queue never activate +disk mode for delayable inputs. So this is probably not what you want. + + +queue.lightDelayMark +-------------------- + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "70% of queue.size", "no", "none" + +If this mark is reached the sender will be throttled if possible. The +main idea to do this is leave some space inside the queue for inputs +like UDP which cannot be throttled - and so any data arriving at +"queue full" would be discarded. + +If the special value `0` is used, `queue.LightDelayMark` will be set +to the value of `queue.size`. This effectively **disables** light delay +functionality. This is useful if a queue is not used by non-delayable +inputs like UDP. The special value was introduced in rsyslog 8.1904.0 +and is **not** available in earlier versions. There, you can achieve the +same result by setting `queue.LightDelayMark` to a very large value. + + +queue.discardMark +----------------- + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "80% of queue.size", "no", "``$ActionQueueDiscardMark``" + +Specifies the threshold at which rsyslog begins to discard less important +messages. To define which messages should be discarded use the +queue.discardseverity parameter. + + +queue.discardSeverity +--------------------- + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "8", "no", "``$ActionQueueDiscardSeverity``" + +As soon as the threshold of the parameter queue.discardMark is reached +incoming as well as queued messages with a priority equal or lower than +specified will be erased. With the default no messages will be erased. +You have to specify a numeric severity value for this parameter. + + +queue.checkpointInterval +------------------------ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "``$ActionQueueCheckpointInterval``" + +Disk queues by default do not update housekeeping structures every time +the queue writes to disk. This is for performance reasons. In the event of failure, +data will still be lost (except when data is mangled via the file structures). +However, disk queues can be set to write bookkeeping information on checkpoints +(every n records), so that this can be made ultra-reliable, too. If the +checkpoint interval is set to one, no data can be lost, but the queue is +exceptionally slow. + + +queue.syncqueuefiles +-------------------- + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "``$ActionQueueSyncQueueFiles``" + +Disk-based queues can be made very reliable by issuing a (f)sync after each +write operation. This happens when you set the parameter to "on". +Activating this option has a performance penalty, so it should not +be turned on without a good reason. Note that the penalty also depends on +*queue.checkpointInterval* frequency. + + +queue.samplingInterval +---------------------- + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "none" + +.. versionadded:: 8.23.0 + +This option allows queues to be populated by events produced at a specific interval. +It provides a way to sample data each N events, instead of processing all, in order +to reduce resources usage (disk, bandwidth...) + + +queue.type +---------- + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "word", "Direct", "no", "``$ActionQueueType``" + +Specifies the type of queue that will be used. Possible options are "FixedArray", +"LinkedList", "Direct" or "Disk". For more information read the documentation +for :doc:`queues <../concepts/queues>`. + + +queue.workerThreads +------------------- + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "1", "no", "``$ActionQueueWorkerThreads``" + +Specifies the maximum number of worker threads that can be run parallel. + + +queue.workerThreadMinimumMessages +--------------------------------- + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "queue.size/queue.workerthreads", "no", "``$ActionQueueWorkerThreadMinimumMessages``" + +Specify the number of messages a worker thread is processing before another +worker thread is created. This number is limited by parameter queue.workerThreads. +For example if this parameter is set to 200 and in the queue are 201 messages a +second worker thread will be created. + + +queue.timeoutWorkerthreadShutdown +--------------------------------- + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "60000", "no", "``$ActionQueueTimeoutWorkerthreadShutdown``" + +After starting a worker thread, it will process messages until there are no +messages for him to process. This parameter specifies the time the worker +thread has to be inactive before it times out. +The parameter must be specified in milliseconds. Which means the default of +60000 is 1 minute. + + +queue.timeoutshutdown +--------------------- + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "10/1500", "no", "``$ActionQueueTimeoutShutdown``" + +If a queue that still contains messages is terminated it will wait the +specified time interval for the worker thread to finish. +The time is specified in milliseconds (1000ms is 1sec). +Default for action queues is 10, for ruleset queues it is 1500. + + +queue.timeoutActionCompletion +----------------------------- + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "1000", "no", "``$ActionQueueTimeoutActionCompletion``" + +When a queue is terminated, the timeout shutdown is over and there is +still data in the queue, the queue will finish the current data element +and then terminate. This parameter specifies the timeout for processing +this last element. +Parameter is specified in milliseconds (1000ms is 1sec). + + +queue.timeoutEnqueue +-------------------- + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "2000", "no", "``$ActionQueueTimeoutEnqueue``" + +This timeout value is used when the queue is full. If rsyslog cannot +enqueue a message within the timeout period, the message is discarded. +Note that this is setting of last resort (assuming defaults are used +for the queue settings or proper parameters are set): all delayable +inputs (like imtcp or imfile) have already been pushed back at this +stage. Also, discarding of lower priority messages (if configured) has +already happened. So we run into one of these situations if we do not +timeout quickly enough: + +* if using imuxsock and no systemd journal is involved, the system + would become unresponsive and most probably a hard reset would be + required. +* if using imuxsock with imjournal forwarding is active, messages are + lost because the journal discards them (more aggressive than rsyslog does) +* if using imjournal, the journal will buffer messages. If journal + runs out of configured space, messages will be discarded. So in this + mode discarding is moved to a bit later place. +* other non-delayable sources like imudp will also loose messages + +So this setting is provided in order to guard against problematic situations, +which always will result either in message loss or system hang. For +action queues, one may debate if it would be better to overflow rapidly +to the main queue. If so desired, this is easy to accomplish by setting +a very large timeout value. The same, of course, is true for the main +queue, but you have been warned if you do so! + +In some other words, you can consider this scenario, using default values. +With all progress blocked (unable to deliver a message): + +* all delayable inputs (tcp, relp, imfile, imjournal, etc) will block + indefinantly (assuming queue.lightdelaymark and queue.fulldelaymark + are set sensible, which they are by default). +* imudp will be loosing messages because the OS will be dropping them +* messages arriving via UDP or imuxsock that do make it to rsyslog, + and that are a severity high enough to not be filtered by + discardseverity, will block for 2 seconds trying to put the message in + the queue (in the hope that something happens to make space in the + queue) and then be dropped to avoid blocking the machine permanently. + + Then the next message to be processed will also be tried for 2 seconds, etc. + +* If this is going into an action queue, the log message will remain + in the main queue during these 2 seconds, and additional logs that + arrive will accumulate behind this in the main queue. + + +queue.maxFileSize +----------------- + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "1m/16m", "no", "``$ActionQueueMaxFileSize``" + +Specifies the maximum size for the disk-assisted queue file. +Parameter can be specified in Mebibyte or Gibibyte, default for action +queues is 1m and for ruleset queues 16m (1m = 1024*1024). + + +queue.saveOnShutdown +-------------------- + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "binary", "off", "no", "``$ActionQueueSaveOnShutdown``" + +This parameter specifies if data should be saved at shutdown. + + +queue.dequeueSlowDown +--------------------- + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "``$ActionQueueDequeueSlowDown``" + +Regulates how long dequeueing should be delayed. This value must be specified +in microseconds (1000000us is 1sec). It can be used to slow down rsyslog so +it won't send things to fast. +For example if this parameter is set to 10000 on a UDP send action, the action +won't be able to put out more than 100 messages per second. + + +queue.dequeueTimeBegin +---------------------- + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "0", "no", "``$ActionQueueDequeueTimeBegin``" + +With this parameter you can specify rsyslog to process queues during specific +time periods. To define a time frame use the 24-hour format without minutes. +This parameter specifies the begin and "queue.dequeuetimeend" the end of the +time frame. + + +queue.dequeueTimeEnd +-------------------- + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "integer", "25", "no", "``$ActionQueueDequeueTimeEnd``" + +With this parameter you can specify rsyslog to process queues during specific +time periods. To define a time frame use the 24-hour format without minutes. +This parameter specifies the end and "queue.dequeuetimebegin" the begin of the +time frame. The default 25 disables the time-window. + + +queue.takeFlowCtlFromMsg +------------------------ + +.. csv-table:: + :header: "type", "default", "mandatory", "|FmtObsoleteName| directive" + :widths: auto + :class: parameter-table + + "boolean", "off", "no", "none" + +.. versionadded:: 8.1911.0 + +This is a fine-tuning parameter which permits to control whether or not +rsyslog shall always take the flow control setting from the message. If +so, non-primary queues may also **block** when reaching high water mark. + +This permits to add some synchronous processing to rsyslog core engine. +However, **this involves some risk**: Improper use may make the core engine +stall. As such, **enabling this parameter requires very careful planning +of the rsyslog configuration and deep understanding of the consequences**. + +Note that the parameter is applied to individual queues, so a configuration +with a large number of queues can (and must if used) be fine-tuned to +the exact use case. + +**The rsyslog team strongly recommends to let this parameter turned off.** + + + +Examples +======== + +Example 1 +--------- + +The following is a sample of a TCP forwarding action with its own queue. + +.. code-block:: none + + action(type="omfwd" target="192.168.2.11" port="10514" protocol="tcp" + queue.filename="forwarding" queue.size="1000000" queue.type="LinkedList" + ) + diff --git a/source/rainerscript/rainerscript_call.rst b/source/rainerscript/rainerscript_call.rst new file mode 100644 index 0000000..1dc3fa3 --- /dev/null +++ b/source/rainerscript/rainerscript_call.rst @@ -0,0 +1,56 @@ +The rsyslog "call" statement +============================ + +The rsyslog "call" statement is used to tie rulesets together. It is +modelled after the usual programming language "call" statement. Think of +a ruleset as a subroutine (what it really is!) and you get the picture. + +The "call" statement can be used to call into any type of rulesets. If a +rule set has a queue assigned, the message will be posted to that queue +and processed asynchronously. Otherwise, the ruleset will be executed +synchronously and control returns to right after the call when the rule +set has finished execution. + +Note that there is an important difference between asynchronous and +synchronous execution in regard to the "stop" statement. It will not +affect processing of the original message when run asynchronously. + +The "call" statement replaces the deprecated omruleset module. It offers +all capabilities omruleset has, but works in a much more efficient way. +Note that omruleset was a hack that made calling rulesets possible +within the constraints of the pre-v7 engine. "call" is the clean +solution for the new engine. Especially for rulesets without associated +queues (synchronous operation), it has zero overhead (really!). +omruleset always needs to duplicate messages, which usually means at +least ~250 bytes of memory writes, some allocs and frees - and even more +performance-intense operations. + + +syntax +------ + +``call rulesetname`` + +Where "rulesetname" is the name of a ruleset that is defined elsewhere +inside the configuration. If the call is synchronous or asynchronous +depends on the ruleset parameters. This cannot be overridden by the +"call" statement. + +compatibility notes +------------------- +Note that versions prior to 8.2110.0 had a bug where an explicit +'queue="direct"' setting in the ruleset definition lead call to treat +this as if a real queue existed. This could lead to some unexpected +behaviour. Beginning with 8.2110.0 this is handled consistently and +correctly. + +Under some exotic circumstances, this may look like a change of +behavior. If so, consider adding a small array-based queue to the +ruleset in question. + +related links +------------- + +- `Blog posting announcing "call" statement (with + sample) <https://rainer.gerhards.net/2012/10/how-to-use-rsyslogs-ruleset-and-call.html>`_ + diff --git a/source/rainerscript/rainerscript_call_indirect.rst b/source/rainerscript/rainerscript_call_indirect.rst new file mode 100644 index 0000000..5bedbe7 --- /dev/null +++ b/source/rainerscript/rainerscript_call_indirect.rst @@ -0,0 +1,58 @@ +The rsyslog "call_indirect" statement +===================================== + +The rsyslog "call_indirect" statement is equivalent to +:doc:`"call" statement <rainerscript_call>` +except that the name of the to be called ruleset is not constant but an +expression and so can be computed at runtime. + +If the ruleset name cannot be found when call_indirect is used, an error +message as emitted and the call_indirect statement is ignored. Execution +continues with the next statement. + +syntax +------ + +``call_indirect expression;`` + +Where "expression" is any valid expression. See +:doc:`expressions <expressions>` +for more information. Note that the trailing semicolon is needed to +indicate the end of expression. If it is not given, config load will +fail with a syntax error message. + +examples +-------- + +The potentially most useful use-case for "call_indirect" is calling a +ruleset based on a message variable. Let us assume that you have named +your rulesets according to syslog tags expected. Then you can use + +``call_indirect $syslogtag;`` + +To call these rulesets. Note, however, that this may be misused by a +malicious attacker, who injects invalid syslog tags. This could especially +be used to redirect message flow to known standard rulesets. To somewhat +mitigate against this, the ruleset name can be slightly mangled by creating +a **unique** prefix (do **not** use the one from this sample). Let us assume +the prefix "changeme-" is used, then all your rulesets should start with that +string. Then, the following call can be used: + +``call_indirect "changeme-" & $syslogtag;`` + +While it is possible to call a ruleset via a constant name: + +``call_indirect "my_ruleset";`` + +It is advised to use the "call" statement for this, as it offers superior +performance in this case. + +additional information +---------------------- + +We need to have two different statements, "call" and "call_indirect" because +"call" already existed at the time "call_indirect" was added. We could not +extend "call" to support expressions, as that would have broken existing +configs. In that case ``call ruleset`` would have become invalid and +``call "ruleset"`` would have to be used instead. Thus we decided to +add the additional "call_indirect" statement for this use case. diff --git a/source/rainerscript/variable_property_types.rst b/source/rainerscript/variable_property_types.rst new file mode 100644 index 0000000..3d0fb0a --- /dev/null +++ b/source/rainerscript/variable_property_types.rst @@ -0,0 +1,107 @@ +Variable (Property) types +========================= + +All rsyslog properties (see the :doc:`properties +<../configuration/properties>` page for a list) can be used in +RainerScript by prefixing them with "$", for example : +:: + + set $.x!host = $hostname; + +In addition, it also supports local variables. Local +variables are local to the current message, but are NOT message +properties (e.g. the "$!" all JSON property does not contain them). + +Only message json (CEE/Lumberjack) properties can be modified by the +**set**, **unset** and **reset** statements, not any other message property. Obviously, +local variables are also modifiable. + +Message JSON property names start with "$!" where the bang character +represents the root. + +Local variables names start with "$.", where the dot denotes the root. + +Both JSON properties as well as local variables may contain an arbitrary +deep path before the final element. The bang character is always used as +path separator, no matter if it is a message property or a local +variable. For example "$!path1!path2!varname" is a three-level deep +message property where as the very similar looking +"$.path1!path2!varname" specifies a three-level deep local variable. The +bang or dot character immediately following the dollar sign is used by +rsyslog to separate the different types. + +Note that the trailing semicolon is needed to indicate the end of expression. +If it is not given, config load will fail with a syntax error message. + +Check the following usage examples to understand how these statements behave: + +**set** +------- +sets the value of a local-variable or json property, but if the addressed +variable already contains a value its behaviour differs as follows: + +**merges** the value if both existing and new value are objects, +but merges the new value to *root* rather than with value of the given key. Eg. + +:: + + set $.x!one = "val_1"; + # results in $. = { "x": { "one": "val_1" } } + set $.y!two = "val_2"; + # results in $. = { "x": { "one": "val_1" }, "y": { "two": "val_2" } } + + set $.z!var = $.x; + # results in $. = { "x": { "one": "val_1" }, "y": { "two": "val_2" }, "z": { "var": { "one": "val_1" } } } + + set $.z!var = $.y; + # results in $. = { "x": { "one": "val_1" }, "y": { "two": "val_2" }, "z": { "var": { "one": "val_1" } }, "two": "val_2" } + # note that the key *two* is at root level and not under *$.z!var*. + +**ignores** the new value if old value was an object, but new value is a not an object (Eg. string, number etc). Eg: + +:: + + set $.x!one = "val_1"; + set $.x = "quux"; + # results in $. = { "x": { "one": "val_1" } } + # note that "quux" was ignored + +**resets** variable, if old value was not an object. + +:: + + set $.x!val = "val_1"; + set $.x!val = "quux"; + # results in $. = { "x": { "val": "quux" } } + +**unset** +--------- +removes the key. Eg: + +:: + + set $.x!val = "val_1"; + unset $.x!val; + # results in $. = { "x": { } } + +**reset** +--------- +force sets the new value regardless of what the variable +originally contained or if it was even set. Eg. + +:: + + # to contrast with the set example above, here is how results would look with reset + set $.x!one = "val_1"; + set $.y!two = "val_2"; + set $.z!var = $.x; + # results in $. = { "x": { "one": "val_1" }, "y": { "two": "val_2" }, "z": { "var": { "one": "val_1" } } } + # 'set' or 'reset' can be used interchangeably above(3 lines), they both have the same behaviour, as variable doesn't have an existing value + + reset $.z!var = $.y; + # results in $. = { "x": { "one": "val_1" }, "y": { "two": "val_2" }, "z": { "var": { "two": "val_2" } } } + # note how the value of $.z!var was replaced + + reset $.x = "quux"; + # results in $. = { "x": "quux", "y": { "two": "val_2" }, "z": { "var": { "two": "val_2" } } } + diff --git a/source/rsyslog-vers.png b/source/rsyslog-vers.png Binary files differnew file mode 100644 index 0000000..e8ec8b8 --- /dev/null +++ b/source/rsyslog-vers.png diff --git a/source/rsyslog_confgraph_complex.png b/source/rsyslog_confgraph_complex.png Binary files differnew file mode 100644 index 0000000..21c04c5 --- /dev/null +++ b/source/rsyslog_confgraph_complex.png diff --git a/source/rsyslog_confgraph_std.png b/source/rsyslog_confgraph_std.png Binary files differnew file mode 100644 index 0000000..655a7f8 --- /dev/null +++ b/source/rsyslog_confgraph_std.png diff --git a/source/tls_cert.jpg b/source/tls_cert.jpg new file mode 100644 index 0000000..3971f85 --- /dev/null +++ b/source/tls_cert.jpg @@ -0,0 +1,12 @@ +--2014-01-22 12:49:25-- http://www.rsyslog.com/doc/tls_cert.jpg +Resolving www.rsyslog.com (www.rsyslog.com)... 176.9.39.152 +Connecting to www.rsyslog.com (www.rsyslog.com)|176.9.39.152|:80... connected. +HTTP request sent, awaiting response... 200 OK +Length: unspecified [image/jpg] +Saving to: ‘tls_cert.jpg’ + + 0K .......... .......... .......... .......... .......... 141K + 50K .......... ...... 146K=0.5s + +2014-01-22 12:49:26 (143 KB/s) - ‘tls_cert.jpg’ saved [68335] + diff --git a/source/tls_cert_100.jpg b/source/tls_cert_100.jpg new file mode 100644 index 0000000..7964533 --- /dev/null +++ b/source/tls_cert_100.jpg @@ -0,0 +1,11 @@ +--2014-01-22 12:50:33-- http://www.rsyslog.com/doc/tls_cert_100.jpg +Resolving www.rsyslog.com (www.rsyslog.com)... 176.9.39.152 +Connecting to www.rsyslog.com (www.rsyslog.com)|176.9.39.152|:80... connected. +HTTP request sent, awaiting response... 200 OK +Length: unspecified [image/jpg] +Saving to: ‘tls_cert_100.jpg’ + + 0K .......... ...... 70.2K=0.2s + +2014-01-22 12:50:34 (70.2 KB/s) - ‘tls_cert_100.jpg’ saved [16607] + diff --git a/source/tls_cert_ca.jpg b/source/tls_cert_ca.jpg new file mode 100644 index 0000000..ca59ec0 --- /dev/null +++ b/source/tls_cert_ca.jpg @@ -0,0 +1,11 @@ +--2014-01-22 12:54:08-- http://www.rsyslog.com/doc/tls_cert_ca.jpg +Resolving www.rsyslog.com (www.rsyslog.com)... 176.9.39.152 +Connecting to www.rsyslog.com (www.rsyslog.com)|176.9.39.152|:80... connected. +HTTP request sent, awaiting response... 200 OK +Length: unspecified [image/jpg] +Saving to: ‘tls_cert_ca.jpg’ + + 0K ......... 83.9K=0.1s + +2014-01-22 12:54:08 (83.9 KB/s) - ‘tls_cert_ca.jpg’ saved [9635] + diff --git a/source/troubleshooting/debug.rst b/source/troubleshooting/debug.rst new file mode 100644 index 0000000..f4de297 --- /dev/null +++ b/source/troubleshooting/debug.rst @@ -0,0 +1,198 @@ +Rsyslog Debug Support +===================== + +For harder to find issues, rsyslog has integrated debug support. Usually, +this is not required for finding configuration issues but rather +to hunt for program or plugin bugs. However, there are several +occasions where debug log has proven to be quite helpful in finding +out configuration issues. + +A :doc:`quick guide can be found here<../troubleshooting/howtodebug>`. + +Signals supported +----------------- + +**SIGUSR1** - turns debug messages on and off. Note that for this signal +to work, rsyslogd must be running with debugging enabled, either via the +-d command line switch or the environment options specified below. It is +**not** required that rsyslog was compiled with debugging enabled (but +depending on the settings this may lead to better debug info). + +**Note:** this signal **may go away** in later releases and may be +replaced by something else. + +Environment Variables +--------------------- + +There are two environment variables that set several debug settings: + +- The "RSYSLOG\_DEBUGLOG" (sample: + RSYSLOG\_DEBUGLOG="/path/to/debuglog/debug.log") writes (almost) all debug + message to the specified log file in addition to stdout. Some system + messages (e.g. segfault or abort message) are not written to the file + as we can not capture them. +- Runtime debug support is controlled by "RSYSLOG\_DEBUG". + + The "RSYSLOG\_DEBUG" environment variable contains an option string + with the following options possible (all are case insensitive): + + - **LogFuncFlow** - print out the logical flow of functions + (entering and exiting them) + - **FileTrace** - specifies which files to trace LogFuncFlow. If + **not** set (the default), a LogFuncFlow trace is provided for all + files. Set to limit it to the files specified. FileTrace may be + specified multiple times, one file each (e.g. export + RSYSLOG\_DEBUG="LogFuncFlow FileTrace=vm.c FileTrace=expr.c" + - **PrintFuncDB** - print the content of the debug function database + whenever debug information is printed (e.g. abort case)! + - **PrintAllDebugInfoOnExit** - print all debug information + immediately before rsyslogd exits (currently not implemented!) + - **PrintMutexAction** - print mutex action as it happens. Useful + for finding deadlocks and such. + - **NoLogTimeStamp** - do not prefix log lines with a timestamp + (default is to do that). + - **NoStdOut** - do not emit debug messages to stdout. If + RSYSLOG\_DEBUGLOG is not set, this means no messages will be + displayed at all. + - **Debug** - if present, turns on the debug system and enables + debug output + - **DebugOnDemand** - if present, turns on the debug system but does + not enable debug output itself. You need to send SIGUSR1 to turn + it on when desired. + - **OutputTidToStderr** - if present, makes rsyslog output + information about the thread id (tid) of newly created processes to + stderr. Note that not necessarily all new threads are reported + (depends on the code, e.g. of plugins). This is only available + under Linux. This usually does NOT work when privileges have been + dropped (that's not a bug, but the way it is). + - **help** - display a very short list of commands - hopefully a + life saver if you can't access the documentation... + + Individual options are separated by spaces. + +Why Environment Variables? +~~~~~~~~~~~~~~~~~~~~~~~~~~ + +You may ask why we use environment variables for debug-system parameters +and not the usual rsyslog.conf configuration commands. After all, +environment variables force one to change distro-specific configuration +files, whereas regular configuration directives would fit nicely into +the one central rsyslog.conf. + +Historically environment variables were necessary to initialize so-called +"rtinst" mode. This mode no longer exists, as the OS tools have improved. +Using environment variables still has the benefit that the work right from +initialization of rsyslogd. Most importantly, this is before the rsyslog.conf +is read. + +If that is no issue, rsyslog.conf global statements can be used to enable +debug mode and provide some settings. + +HOWEVER, if you have a too hard time to set debug instructions using the +environment variables, there is a cure, described in the next paragraph. + +Enabling Debug via rsyslog.conf +------------------------------- + +As described in the previous paragraph, enabling debug via rsyslog.conf +may not be perfect for some debugging needs, but basic debug output will +work - and that is what most often is required. There are limited +options available, but these cover the most important use cases. + +Debug processing is done via legacy config statements. There currently +is no plan to move these over to the v6+ config system. Available +settings are + +- $DebugFile <filename> - sets the debug file name +- $DebugLevel <0\|1\|2> - sets the respective debug level, where 0 + means debug off, 1 is debug on demand activated (but debug mode off) + and 2 is full debug mode. + +Note that in theory it is forbidden to specify these parameters more +than once. However, we do not enforce that and if it happens results are +undefined. + +Getting debug information from a running Instance +------------------------------------------------- + +It is possible to obtain debugging information from a running instance, +but this requires some setup. We assume that the instance runs in the +background, so debug output to stdout is not desired. As such, all debug +information needs to go into a log file. + +To create this setup, you need to + +- point the RSYSLOG\_DEBUGLOG environment variable to a file that is + accessible during the while runtime (we strongly suggest a file in + the local file system!) +- set RSYSLOG\_DEBUG at least to "DebugOnDeman NoStdOut" +- make sure these environment variables are set in the correct + (distro-specific) startup script if you do not run rsyslogd + interactively + +These settings enable the capability to react to SIGUSR1. The signal +will toggle debug status when received. So send it once to turn debug +logging on, and send it again to turn debug logging off again. The third +time it will be turned on again ... and so on. + +On a typical system, you can signal rsyslogd as follows: + +:: + + kill -USR1 $(cat /var/run/rsyslogd.pid) + +The debug log will show whether debug +logging has been turned on or off. There is no other indication of the +status. + +Note: running with DebugOnDemand by itself does in practice not have any +performance toll. However, switching debug logging on has a severe +performance toll. Also, debug logging synchronizes much of the code, +removing a lot of concurrency and thus potential race conditions. As +such, the very same running instance may behave very differently with +debug logging turned on vs. off. The on-demand debug log functionality +is considered to be very valuable to analyze hard-to-find bugs that only +manifest after a long runtime. Turning debug logging on a failing +instance may reveal the cause of the failure. However, depending on the +failure, debug logging may not even be successfully turned on. Also +note that with this rsyslog version we cannot obtain any debug +information on events that happened *before* debug logging was turned +on. + + +Interpreting the Logs +--------------------- + +Debug logs are primarily meant for rsyslog developers. But they may +still provide valuable information to users. Just be warned that logs +sometimes contains information the looks like an error, but actually is +none. We put a lot of extra information into the logs, and there are +some cases where it is OK for an error to happen, we just wanted to +record it inside the log. The code handles many cases automatically. So, +in short, the log may not make sense to you, but it (hopefully) makes +sense to a developer. Note that we developers often need many lines of +the log file, it is relatively rare that a problem can be diagnosed by +looking at just a couple of (hundred) log records. + +Security Risks +-------------- + +The debug log will reveal potentially sensible information, including +user accounts and passwords, to anyone able to read the log file. As +such, it is recommended to properly guard access to the log file. Also, +an instance running with debug log enabled runs much slower than one +without. An attacker may use this to place carry out a denial-of-service +attack or try to hide some information from the log file. As such, it is +suggested to enable DebugOnDemand mode only for a reason. Note that when +no debug mode is enabled, SIGUSR1 is completely ignored. + +When running in any of the debug modes (including on demand mode), an +interactive instance of rsyslogd can be aborted by pressing ctl-c. + +See Also +-------- + +- `How to use debug on + demand <http://www.rsyslog.com/how-to-use-debug-on-demand/>`_ +- :doc:`Quick debug guide<../troubleshooting/howtodebug>` + diff --git a/source/troubleshooting/file_not_written.rst b/source/troubleshooting/file_not_written.rst new file mode 100644 index 0000000..4ed915d --- /dev/null +++ b/source/troubleshooting/file_not_written.rst @@ -0,0 +1,53 @@ +Output File is not Being Written +================================ + +Note: current rsyslog versions have somewhat limited error reporting +inside omfile. If a problem persists, you may want to generate a +rsyslog debug log, which often can help you pinpoint the actual root +cause of the problem more quickly. + +To learn more about the current state of error reporting, follow +our `bug tracker <https://github.com/rsyslog/rsyslog/issues/548>`_ +for this issue. + +The following subsections list frequent causes for file writing +problems. You can quickly check this without the need to create a +debug log. + +SELinux +------- +This often stems back to **selinux** permission errors, especially +if files outside of the ``/var/log`` directory shall be written +to. + +Follow the :doc:`SELinux troubleshooting guide <selinux>` +to check for this condition. + +Max Number of Open Files +------------------------ +This can also be caused by a too low limit on number of open +file handles, especially when dynafiles are being written. + +Note that some versions of systemd limit the process +to 1024 files by default. The current +set limit can be validated by doing:: + + cat /proc/<pid>/limits + +and the currently open number of files can be obtained by doing:: + + ls /proc/<pid>/fd | wc -l + +Also make sure the system-wide max open files is appropriate using:: + + sysctl fs.file-max + +Some versions of systemd completely ignore +``/etc/security/limits*``. To change limits for a service in systemd, edit +``/usr/lib/systemd/system/rsyslog.service`` and under ``[Service]`` add: +``LimitNOFILE=<new value>``. + +Then run:: + + systemctl daemon-reload + systemctl restart rsyslog diff --git a/source/troubleshooting/howtodebug.rst b/source/troubleshooting/howtodebug.rst new file mode 100644 index 0000000..5d770ff --- /dev/null +++ b/source/troubleshooting/howtodebug.rst @@ -0,0 +1,57 @@ +How to create a debug log +========================= + +Creating a debug log is actually quite simple. You just have to add a +few lines to the configuration file. + +Regular debug output +-------------------- + +Add the following right at the beginning of the rsyslog.conf file. This +will ensure that debug support is the first thing to enable when the +rsyslog service is started: + +:: + + $DebugFile /var/log/rsyslog.debug + $DebugLevel 2 + +The actual file path and name may be changed if required. + +Having set the above, when rsyslog is restarted it will produce a continuous +debug file. + +Debug on Demand +--------------- + +For having rsyslog be ready to create a debug log (aka Debug on Demand), the +settings are a little different. + +:: + + $DebugFile /var/log/rsyslog.debug + $DebugLevel 1 + +Now, rsyslog will not create a debug log on restart, but wait for a USR signal +to the pid. When sent, the debug output will be triggered. When sent again, +debug output will be stopped. + +:: + + kill -USR1 `cat /var/run/rsyslogd.pid` + +Notes +----- + +- Having debug output enabled, the debug file will grow very quickly. Make sure + to not have it enabled permanently. The file will eventually fill up the disk. +- Debug mode is not to be used in a productive environment as a permanent setting. + It will affect the processing and performance. + +See Also +-------- + +- :doc:`Troubleshooting <../troubleshooting/troubleshoot>` doc page. +- :doc:`Debug Support<../troubleshooting/debug>` doc page with more detailed + information. + diff --git a/source/troubleshooting/index.rst b/source/troubleshooting/index.rst new file mode 100644 index 0000000..4fc3c95 --- /dev/null +++ b/source/troubleshooting/index.rst @@ -0,0 +1,19 @@ +Troubleshooting +=============== + +Typical Problems +---------------- +.. toctree:: + :maxdepth: 1 + + file_not_written + selinux + +General Procedure +----------------- +.. toctree:: + :maxdepth: 2 + + debug + troubleshoot + howtodebug diff --git a/source/troubleshooting/selinux.rst b/source/troubleshooting/selinux.rst new file mode 100644 index 0000000..5646067 --- /dev/null +++ b/source/troubleshooting/selinux.rst @@ -0,0 +1,27 @@ +Troubleshooting SELinux-Related Issues +====================================== + +SELinux by its very nature can block many features of rsyslog (or any +other process, of course), even when run under root. Actually, this is +what it is supposed to do, so there is nothing bad about it. + +If you suspect that some issues stems back to SELinux configuration, +do the following: + +* *temporarily* disable SELinux +* restart rsyslog +* retry the operation + +If it now succeeds, you know that you have a SELinux policy issue. +The solution here is **not** to keep SELinux disabled. Instead do: + +* reenable SELinux (set back to previous state, whatever that was) +* add proper SELinux policies for what you want to do with rsyslog + +With SELinux running, restart rsyslog +$ sudo audit2allow -a +audit2allow will read the audit.log and list any SELinux infractions, namely the rsyslog infractions +$ sudo audit2allow -a -M <FRIENDLY_NAME_OF_MODULE>.pp +audit2allow will create a module allowing all previous infractions to have access +$ sudo semodule -i <FRIENDLY_NAME_OF_MODULE>.pp +Your module is loaded! Restart rsyslog and continue to audit until no more infractions are detected and rsyslog has proper access. Additionally, you can save these modules and install them on future machines where rsyslog will need the same access. diff --git a/source/troubleshooting/troubleshoot.rst b/source/troubleshooting/troubleshoot.rst new file mode 100644 index 0000000..9881864 --- /dev/null +++ b/source/troubleshooting/troubleshoot.rst @@ -0,0 +1,407 @@ +troubleshooting problems +======================== + +**Having trouble with** `rsyslog <https://www.rsyslog.com>`_? This page +provides some tips on where to look for help and what to do if you need +to ask for assistance. This page is continuously being expanded. + +Useful troubleshooting resources are: + +- The `rsyslog documentation <https://www.rsyslog.com/doc>`_ - note that + the online version always covers the most recent development version. + However, there is a version-specific doc set in each tarball. If you + installed rsyslog from a package, there usually is a rsyslog-doc + package, that often needs to be installed separately. + +- Check the `rsyslog github issue tracker <https://github.com/rsyslog/rsyslog/issues>`_ and + `the bugzilla <http://bugzilla.adiscon.com>`_ to see if your + problem is a known (and even fixed ;)) bug. + **Note:** the preferred way to create new bugs is via github. + The bugzilla does no longer accept new bugs. It is just kept + to work on old ones and as a reference source for ChangeLog entries. + +Malformed Messages and Message Properties +----------------------------------------- + +A common trouble source are `ill-formed syslog +messages <syslog_parsing.html>`_, which lead to to all sorts of +interesting problems, including malformed hostnames and dates. Read the +quoted guide to find relief. A common symptom is that the %HOSTNAME% +property is used for generating dynafile names, but some gibberish +shows up. This is caused by the malformed syslog messages, so be sure to +read the :doc:`guide on syslog parsing <../whitepapers/syslog_parsing>` +if you face that problem. Just +let me add that the common work-around is to use %FROMHOST% or +%FROMHOST-IP% instead. These do not take the hostname from the message, +but rather use the host that sent the message (taken from the socket +layer). Of course, this does not work over NAT or relay chains, where +the only cure is to make sure senders emit well-formed messages. + +Configuration Problems +---------------------- + +Rsyslog has support for +configuration checking. It offers a special command line switch (-N<*value*>) +that puts it into "config verification mode". In that mode, it interprets +and checks the configuration file, but does not startup. This mode can be +used in parallel to a running instance of rsyslogd. + +Please note that many distros have (unfortunately) begun to split the rsyslog +config into many small config snippets (a.k.a input files), usually in `/etc/rsyslog.d`. From +rsyslog's point of view, only a single config file exists and these snippets +are logically combined into that single config. For that reason, config checking +does usually **not** work on snippets. Because the interdependencies are missing. +For example, binding a ruleset to a module that is not possible if the ruleset is +loaded outside of the snippet. + +**As a general guideline, never do config checks on config snippets. Always use +the main configuration file as a starting point** (usually /etc/rsyslog.conf`). + +The *value* given after -N is a set of binary values. Currently, there only is + +======= ====================================== +value meaning +1 turn on config checking +2 permit checking of include files +======= ====================================== + +Where 2 automatically turns on config checking mode, if not given. In that +sense ``-N2`` and ``-N3`` are equivalent. + +Values other than given in the table above are **not** supported and may lead +to unpredictable results. + +When set to check include files, some conditions are relaxed. For example, +rsyslog usually requires that at least one action is defined somewhere in +the configuration. For obvious reasons, it would not make much sense to run +an instance without any action. However, when an include file is checked, +it may happen that it contains no actions as all. As such, the requirement +to include one action has been lifted in include file checking. + +To check a full rsyslog configuration, run rsyslog interactively as follows: + +:: + + $ /path/to/rsyslogd -f/path/to/config-file -N1 + +You should also specify other options you usually give. +Any problems experienced are reported to stderr [aka +"your screen" (if not redirected)]. + +If you would like to check just an include file, instead use: + +:: + + $ /path/to/rsyslogd -f/path/to/config-file -N3 + +Sometimes problems are rooted in config include files, and especially the +order in which they are processed. To troubleshoot these kinds of issues, you +can use the rsyslogd `-o` option: it permits to specify a file that shall +receive a full copy of rsyslog's current configuration **as rsyslog sees it**. +This means all include file content is directly inside that file at +exactly the spot where rsyslog sees it. The output file is almost a +verbatim copy of the original full rsyslog config. For troubleshooting +purposes it additionally contains comment lines that indicate where +content from specific include files begins and ends. The include file +is correctly named in these comments. + +This option can be used together with `-N`. Again, it is best to run +rsyslog interactively. Do as such:: + + $ /path/to/rsyslogd -f/path/to/config-file -N3 -o /path/to/full-conf-file + + +Checking Connection Problems +---------------------------- + +If a client cannot connect via the network to the rsyslog server, you +can do a connection check via netcat. That will verify if the sender +is able to deliver to an application running on the receiver. Netcat +is a very simple receiver, so we can be sure that no netcat problem +will interfere with this test. + +With netcat, you can test UDP and TCP syslog connections, but not TLS. + +To do this test, you need to + +* on the client + + - stop the syslog sender process, if possible. If the sender is + rsyslog, you can use the same procedure described below for the + server. + +* on the rsyslog server + + - stop and/or disable rsyslog + On systemd systems (newer distro versions), systemd might + automatically restart rsyslog when data is written to the system + log socket. To be sure, we recommend to disable the service on + those systems. This sequence should work: + $ systemctl disable rsyslog.service + $ systemctl stop rsyslog.service + + - open a terminal session, and start a netcat listener **on the same + listening port** that you have configured inside rsyslog. Note that + if you use a privileged port, you need to execute nc as root. + We assume port 13515 is used for rsyslog, so do this: + $ nc -k -l <ip-of-server> 13515 # [FOR TCP] OR sudo nc ... + $ nc -u -l <ip-of-server> 13515 # [FOR UDP] OR sudo nc ... + +* on the syslog client + + - send a test message via netcat: + $ echo "test message 1" | nc <ip-of-server> 13515 # [FOR TCP] + $ echo "test message 1" | nc <ip-of-server> 13515 # [FOR UDP] + +* on the server + + - check if you received the test message. Note that you might also + have received additional messages if the original sender process + was not stopped. If you see garbage, most probably some sender + tries to send via TLS. + - you can stop nc by <ctl>-c + +If you did not see the test message arrive at the central server, +the problem is most probably rooted in the network configuration +or other parts of the system configuration. Things to check are +- firewall settings + +- for UDP: does the sender have a route back to the original sender? + This is often required by modern systems to prevent spoofing; if the + sender cannot be reached, UDP messages are discarded AFTER they have + been received by the OS (an app like netcat or rsyslog will never + see them) + +- if that doesn't help, use a network monitor (or tcpdump, Wireshark, ...) + to verify that the network packet at least reaches the system. + +If you saw the test message arrive at the central server, the problem +most probably is related to the rsyslog configuration or the system +configuration that affects rsyslog (SELinux, AppArmor, ...). + +A good next test is to run rsyslog interactively, just like you did +with netcat: + +* on the server + - make sure the rsyslog service is still stopped + + - run + $ sudo /usr/sbin/rsyslogd -n + +* on the client + + - send a test message + +* on the server + - check if the message arrived + + - terminate rsyslog by pressing <ctl>-c + +If the test message arrived, you definitely have a problem with the +system configuration, most probably in SELinux, AppArmor or a similar +subsystem. Note that your interactive security context is quite different +from the rsyslog system service context. + +If the test message did not arrive, it is time to generate a debug +log to see exactly what rsyslog does. A full description is in this file +a bit down below, but in essence you need to do + +* on the server + - make sure the rsyslog service is still stopped + - run + + $ sudo /usr/sbin/rsyslogd -nd 2> rsyslog-debug.log + +* on the client + - send a test message + +* on the server + - stop rsyslog by pressing <ctl>- + - review debug log + + +Asking for Help +--------------- + +If you can't find the answer yourself, you should look at these places +for community help. + +- The `rsyslog mailing + list <http://lists.adiscon.net/mailman/listinfo/rsyslog>`_. This is a + low-volume list which occasional gets traffic spikes. The mailing + list is probably a good place for complex questions. + This is the preferred method of obtaining support. +- The `rsyslog forum <http://kb.monitorware.com/rsyslog-f40.html>`_. + +Debug Log +--------- + +If you ask for help, there are chances that we need to ask for an +rsyslog debug log. The debug log is a detailed report of what rsyslog +does during processing. As such, it may even be useful for your very own +troubleshooting. People have seen things inside their debug log that +enabled them to find problems they did not see before. So having a look +at the debug log, even before asking for help, may be useful. + +Note that the debug log contains most of those things we consider +useful. This is a lot of information, but may still be too few. So it +sometimes may happen that you will be asked to run a specific version +which has additional debug output. Also, we revise from time to time +what is worth putting into the standard debug log. As such, log content +may change from version to version. We do not guarantee any specific +debug log contents, so do not rely on that. The amount of debug logging +can also be controlled via some environment options. Please see +`debugging support <debug.html>`_ for further details. + +In general, it is advisable to run rsyslogd in the foreground to obtain +the log. To do so, make sure you know which options are usually used +when you start rsyslogd as a background daemon. Let's assume "-c5" is +the only option used. Then, do the following: + +- make sure rsyslogd as a daemon is stopped (verify with ps -ef\|grep + rsyslogd) +- make sure you have a console session with root permissions +- run rsyslogd interactively: ```/sbin/rsyslogd ..your options.. -dn > + logfile``` + where "your options" is what you usually use. /sbin/rsyslogd is the + full path to the rsyslogd binary (location different depending on + distro). In our case, the command would be + ```/sbin/rsyslogd -c5 -dn > logfile``` +- press ctrl-C when you have sufficient data (e.g. a device logged a + record) + **NOTE: rsyslogd will NOT stop automatically - you need to ctrl-c out + of it!** +- Once you have done all that, you can review logfile. It contains the + debug output. +- When you are done, make sure you re-enable (and start) the background + daemon! + +If you need to submit the logfile, you may want to check if it contains +any passwords or other sensitive data. If it does, you can change it to +some **consistent** meaningless value. **Do not delete the lines**, as +this renders the debug log unusable (and makes Rainer quite angry for +wasted time, aka significantly reduces the chance he will remain +motivated to look at your problem ;)). For the same reason, make sure +whatever you change is change consistently. Really! + +Debug log file can get quite large. Before submitting them, it is a good +idea to zip them. Rainer has handled files of around 1 to 2 GB. If +your's is larger ask before submitting. Often, it is sufficient to +submit the first 2,000 lines of the log file and around another 1,000 +around the area where you see a problem. Also, ask you can submit a file +via private mail. Private mail is usually a good way to go for large +files or files with sensitive content. However, do NOT send anything +sensitive that you do not want the outside to be known. While Rainer so +far made effort no to leak any sensitive information, there is no +guarantee that doesn't happen. If you need a guarantee, you are probably +a candidate for a `commercial support +contract <http://www.rsyslog.com/professional-services/>`_. Free support comes without any +guarantees, include no guarantee on confidentiality [aka "we don't want +to be sued for work were are not even paid for ;)]. **So if you submit +debug logs, do so at your sole risk**. By submitting them, you accept +this policy. + +Segmentation Faults +------------------- + +Rsyslog has a very rapid development process, complex capabilities and +now gradually gets more and more exposure. While we are happy about +this, it also has some bad effects: some deployment scenarios have +probably never been tested and it may be impossible to test them for the +development team because of resources needed. So while we try to avoid +this, you may see a serious problem during deployments in demanding, +non-standard, environments (hopefully not with a stable version, but +chances are good you'll run into troubles with the development +versions). + +In order to aid the debugging process, it is useful to have debug symbols +on the system. If you build rsyslog yourself, make sure that the ``-g`` +option is included in CFLAGS. If you use packages, the debug symbols come +in their own package. **It is highly recommended to install that package +as it provides tremendous extra benefit.** To do so, do: + +:: + + yum install rsyslog-debuginfo + +Obviously, this is for RPM-based systems, but it's essentially the same +with other packaging systems, just use the native commands. Note that +the package may be named slightly different, but it should always be +fairly easy to locate. + + +Active support from the user base is very important to help us track +down those things. Most often, serious problems are the result of some +memory misaddressing. During development, we routinely use valgrind, a +very well and capable memory debugger. This helps us to create pretty +clean code. But valgrind can not detect everything, most importantly not +code paths that are never executed. So of most use for us is +information about aborts and abort locations. + +Unfortunately, faults rooted in addressing errors typically show up only +later, so the actual abort location is in an unrelated spot. To help +track down the original spot, `libc later than 5.4.23 offers +support <http://www.gnu.org/software/hello/manual/libc/Heap-Consistency-Checking.html>`_ +for finding, and possible temporary relief from it, by means of the +MALLOC\_CHECK\_ environment variable. Setting it to 2 is a useful +troubleshooting aid for us. It will make the program abort as soon as +the check routines detect anything suspicious (unfortunately, this may +still not be the root cause, but hopefully closer to it). Setting it to +0 may even make some problems disappear (but it will NOT fix them!). +With functionality comes cost, and so exporting MALLOC\_CHECK\_ without +need comes at a performance penalty. However, we strongly recommend +adding this instrumentation to your test environment should you see any +serious problems. Chances are good it will help us interpret a dump +better, and thus be able to quicker craft a fix. + +In order to get useful information, we need some backtrace of the abort. +First, you need to make sure that a core file is created. Under Fedora, +for example, that means you need to have an "ulimit -c unlimited" in +place. + +Now let's assume you got a core file (e.g. in /core.1234). So what to do +next? Sending a core file to us is most often pointless - we need to +have the exact same system configuration in order to interpret it +correctly. Obviously, chances are extremely slim for this to be. So we +would appreciate if you could extract the most important information. +This is done as follows: + +:: + + $ gdb /path/to/rsyslogd + $ core /core.1234 + $ info thread + $ thread apply all bt full + $ q # quits gdb + +The same method can be applied to a running rsyslog process that suffers +from a lock condition. E.g. if you experience that rsyslog is no longer +forwarding log messages, but this cannot be reproduced in our lab. Using +gdb to review the state of the active threads may be an option to see +which thread is causing the problem (e.g. by locking itself or being in a +wait state). + +Again, basically the same steps can be applied. But, instead of using a +core file, we will require the currently used PID. So make sure to acquire +the PID before executing gdb. + +:: + + $ gdb /path/to/rsyslogd + $ attach PID # numerical value + $ info thread + $ thread apply all bt full + $ q # quits gdb + +Then please send all information that gdb spit out to the development +team. It is best to first ask on the forum or mailing list on how to do +that. The developers will keep in contact with you and, I fear, will +probably ask for other things as well ;) + + +Note that we strive for highest reliability of the engine even in +unusual deployment scenarios. Unfortunately, this is hard to achieve, +especially with limited resources. So we are depending on cooperation +from users. This is your chance to make a big contribution to the +project without the need to program or do anything else except get a +problem solved. diff --git a/source/tutorials/cert-script.tar.gz b/source/tutorials/cert-script.tar.gz Binary files differnew file mode 100644 index 0000000..8600b5d --- /dev/null +++ b/source/tutorials/cert-script.tar.gz diff --git a/source/tutorials/database.rst b/source/tutorials/database.rst new file mode 100644 index 0000000..7cc6f3c --- /dev/null +++ b/source/tutorials/database.rst @@ -0,0 +1,280 @@ +Writing syslog messages to MySQL, PostgreSQL or any other supported Database +============================================================================ + +*Written by* \ `Rainer Gerhards <https://rainer.gerhards.net>`_\ *with +some additions by Marc Schiffbauer (2008-02-28)* + +Abstract +-------- + +***In this paper, I describe how to +write***\ `syslog <http://www.monitorware.com/en/topics/syslog/>`_\ ***messages +to +a***\ `MySQL <http://www.mysql.com/>`_\ ***or***\ `PostgreSQL <http://www.postgresql.org/>`_\ ***database.***\ *Having +syslog messages in a database is often handy, especially when you intend +to set up a front-end for viewing them. This paper describes an approach +with*\ `rsyslogd <http://www.rsyslog.com/>`_\ *, an alternative enhanced +syslog daemon natively supporting MySQL and PostgreSQL. I describe the +components needed to be installed and how to configure them. Please note +that as of this writing, rsyslog supports a variety of databases. While +this guide is still MySQL- and PostgreSQL-focused, you can probably use +it together with other ones too. You just need to modify a few +settings.* + +Background +---------- + +In many cases, syslog data is simply written to text files. This +approach has some advantages, most notably it is very fast and +efficient. However, data stored in text files is not readily accessible +for real-time viewing and analysis. To do that, the messages need to be +in a database. There are various ways to store syslog messages in a +database. For example, some have the syslogd write text files which are +later feed via a separate script into the database. Others have written +scripts taking the data (via a pipe) from a non-database-aware syslogd +and store them as they appear. Some others use database-aware syslogds +and make them write the data directly to the database. In this paper, I +use that "direct write" approach. I think it is superior, because the +syslogd itself knows the status of the database connection and thus can +handle it intelligently (well ... hopefully ;)). I use rsyslogd to +accomplish this, simply because I have initiated the rsyslog project with +database-awareness as one goal. + +**One word of caution:** while message storage in the database provides +an excellent foundation for interactive analysis, it comes at a cost. +Database i/o is considerably slower than text file i/o. As such, +directly writing to the database makes sense only if your message volume +is low enough to allow a) the syslogd, b) the network, and c) the +database server to catch up with it. Some time ago, I have written a +paper on `optimizing syslog server +performance <http://www.monitorware.com/Common/en/Articles/performance-optimizing-syslog-server.php>`_. +While this paper talks about Window-based solutions, the ideas in it are +generic enough to apply here, too. So it might be worth reading if you +anticipate medium high to high traffic. If you anticipate really high +traffic (or very large traffic spikes), you should seriously consider +forgetting about direct database writes - in my opinion, such a +situation needs either a very specialized system or a different approach +(the text-file-to-database approach might work better for you in this +case). + +Overall System Setup +-------------------- + +In this paper, I concentrate on the server side. If you are thinking +about interactive syslog message review, you probably want to centralize +syslog. In such a scenario, you have multiple machines (the so-called +clients) send their data to a central machine (called server in this +context). While I expect such a setup to be typical when you are +interested in storing messages in the database, I do not describe how to +set it up. This is beyond the scope of this paper. If you search a +little, you will probably find many good descriptions on how to +centralize syslog. If you do that, it might be a good idea to do it +securely, so you might also be interested in my paper on `ssl-encrypting +syslog message +transfer <http://www.rsyslog.com/doc-rsyslog_stunnel.html>`_. + +No matter how the messages arrive at the server, their processing is +always the same. So you can use this paper in combination with any +description for centralized syslog reporting. + +As I already said, I use rsyslogd on the server. It has intrinsic +support for talking to the supported databases. For obvious reasons, we +also need an instance of MySQL or PostgreSQL running. To keep us +focused, the setup of the database itself is also beyond the scope of +this paper. I assume that you have successfully installed the database +and also have a front-end at hand to work with it (for example, +`phpMyAdmin <http://www.phpmyadmin.net/>`_ or +`phpPgAdmin <http://phppgadmin.sourceforge.net/>`_. Please make sure +that this is installed, actually working and you have a basic +understanding of how to handle it. + +Setting up the system +--------------------- + +You need to download and install rsyslogd first. Obtain it from the +`rsyslog site <http://www.rsyslog.com/>`_. Make sure that you disable +stock syslogd, otherwise you will experience some difficulties. On some +distributions (Fedora 8 and above, for example), rsyslog may already by +the default syslogd, in which case you obviously do not need to do +anything specific. For many others, there are prebuild packages +available. If you use either, please make sure that you have the +required database plugins for your database available. It usually is a +separate package and typically **not** installed by default. + +It is important to understand how rsyslogd talks to the database. In +rsyslogd, there is the concept of "templates". Basically, a template is +a string that includes some replacement characters, which are called +"properties" in rsyslog. Properties are accessed via the "`Property +Replacer <http://www.rsyslog.com/doc-property_replacer.html>`_\ ". +Simply said, you access properties by including their name between +percent signs inside the template. For example, if the syslog message is +"Test", the template "%msg%" would be expanded to "Test". Rsyslogd +supports sending template text as a SQL statement to the database. As +such, the template must be a valid SQL statement. There is no limit in +what the statement might be, but there are some obvious and not so +obvious choices. For example, a template "drop table xxx" is possible, +but does not make an awful lot of sense. In practice, you will always +use an "insert" statement inside the template. + +An example: if you would just like to store the msg part of the full +syslog message, you have probably created a table "syslog" with a single +column "message". In such a case, a good template would be "insert into +syslog(message) values ('%msg%')". With the example above, that would be +expanded to "insert into syslog(message) values('Test')". This expanded +string is then sent to the database. It's that easy, no special magic. +The only thing you must ensure is that your template expands to a proper +SQL statement and that this statement matches your database design. + +Does that mean you need to create database schema yourself and also must +fully understand rsyslogd's properties? No, that's not needed. Because +we anticipated that folks are probably more interested in getting things +going instead of designing them from scratch. So we have provided a +default schema as well as build-in support for it. This schema also +offers an additional benefit: rsyslog is part of +`Adiscon <http://www.adiscon.com/en/>`_'s `MonitorWare product +line <http://www.monitorware.com/en/>`_ (which includes open source and +closed source members). All of these tools share the same default schema +and know how to operate on it. For this reason, the default schema is +also called the "MonitorWare Schema". If you use it, you can simply add +`phpLogCon, a GPLed syslog web interface <http://www.phplogcon.org/>`_, +to your system and have instant interactive access to your database. So +there are some benefits in using the provided schema. + +The schema definition is contained in the file "createDB.sql". It comes +with the rsyslog package and one can be found for each supported +database type (in the plugins directory). Review it to check that the +database name is acceptable for you. Be sure to leave the table and +field names unmodified, because otherwise you need to customize +rsyslogd's default sql template, which we do not do in this paper. Then, +run the script with your favorite SQL client. Double-check that the +table was successfully created. + +It is important to note that the correct database encoding must be used +so that the database will accept strings independent of the string +encoding. This is an important part because it can not be guarantied +that all syslog messages will have a defined character encoding. This is +especially true if the rsyslog-Server will collect messages from +different clients and different products. + +For example PostgreSQL may refuse to accept messages if you would set +the database encoding to “UTF8” while a client is sending invalid byte +sequences for that encoding. + +Database support in rsyslog is integrated via loadable plugin modules. +To use the database functionality, the database plugin must be enabled +in the config file BEFORE the first database table action is used. This +is done by placing the + + ``$ModLoad ommysql`` + +directive at the beginning of /etc/rsyslog.conf for MySQL and + + ``$ModLoad ompgsql`` + +for PostgreSQL. + +For other databases, use their plugin name (e.g. omoracle). + +Next, we need to tell rsyslogd to write data to the database. As we use +the default schema, we do NOT need to define a template for this. We can +use the hardcoded one (rsyslogd handles the proper template linking). So +all we need to do e.g. for MySQL is add a simple selector line to +/etc/rsyslog.conf: + + ``*.* :ommysql:database-server,database-name,database-userid,database-password`` + +Again, other databases have other selector names, e.g. ":ompgsql:" +instead of ":ommysql:". See the output plugin's documentation for +details. + +In many cases, the database will run on the local machine. In this case, +you can simply use "127.0.0.1" for *database-server*. This can be +especially advisable, if you do not need to expose the database to any +process outside of the local machine. In this case, you can simply bind +it to 127.0.0.1, which provides a quite secure setup. Of course, rsyslog +also supports remote database instances. In that case, use the remote +server name (e.g. mydb.example.com) or IP-address. The *database-name* +by default is "Syslog". If you have modified the default, use your name +here. *Database-userid* and *-password* are the credentials used to +connect to the database. As they are stored in clear text in +rsyslog.conf, that user should have only the least possible privileges. +It is sufficient to grant it INSERT privileges to the systemevents +table, only. As a side note, it is strongly advisable to make the +rsyslog.conf file readable by root only - if you make it world-readable, +everybody could obtain the password (and eventually other vital +information from it). In our example, let's assume you have created a +database user named "syslogwriter" with a password of "topsecret" (just +to say it bluntly: such a password is NOT a good idea...). If your +database is on the local machine, your rsyslog.conf line might look like +in this sample: + + ``*.* :ommysql:127.0.0.1,Syslog,syslogwriter,topsecret`` + +Save rsyslog.conf, restart rsyslogd - and you should see syslog messages +being stored in the "systemevents" table! + +The example line stores every message to the database. Especially if you +have a high traffic volume, you will probably limit the amount of +messages being logged. This is easy to accomplish: the "write database" +action is just a regular selector line. As such, you can apply normal +selector-line filtering. If, for example, you are only interested in +messages from the mail subsystem, you can use the following selector +line: + + ``mail.* :ommysql:127.0.0.1,syslog,syslogwriter,topsecret`` + +Review the +`rsyslog.conf <http://www.rsyslog.com/doc-rsyslog_conf.html>`_ +documentation for details on selector lines and their filtering. + +**You have now completed everything necessary to store syslog messages +to the a database.** If you would like to try out a front-end, you might +want to look at `phpLogCon <http://www.phplogcon.org/>`_, which displays +syslog data in a browser. As of this writing, phpLogCon is not yet a +powerful tool, but it's open source, so it might be a starting point for +your own solution. + +On Reliability... +----------------- + +Rsyslogd writes syslog messages directly to the database. This implies +that the database must be available at the time of message arrival. If +the database is offline, no space is left or something else goes wrong - +rsyslogd can not write the database record. If rsyslogd is unable to +store a message, it performs one retry. This is helpful if the database +server was restarted. In this case, the previous connection was broken +but a reconnect immediately succeeds. However, if the database is down +for an extended period of time, an immediate retry does not help. + +Message loss in this scenario can easily be prevented with rsyslog. All +you need to do is run the database writer in queued mode. This is now +described in a generic way and I do not intend to duplicate it here. So +please be sure to read "`Handling a massive syslog database insert rate +with +Rsyslog <http://www.rsyslog.com/doc-rsyslog_high_database_rate.html>`_\ ", +which describes the scenario and also includes configuration examples. + +Conclusion +---------- + +With minimal effort, you can use rsyslogd to write syslog messages to a +database. You can even make it absolutely fail-safe and protect it +against database server downtime. Once the messages are arrived there, +you can interactively review and analyze them. In practice, the messages +are also stored in text files for longer-term archival and the databases +are cleared out after some time (to avoid becoming too slow). If you +expect an extremely high syslog message volume, storing it in real-time +to the database may outperform your database server. In such cases, +either filter out some messages or used queued mode (which in general is +recommended with databases). + +The method outlined in this paper provides an easy to setup and maintain +solution for most use cases. + +References and Additional Material +---------------------------------- + +- `www.rsyslog.com <http://www.rsyslog.com/>`_ - the rsyslog site + +- `Paper on Syslog Server + Optimization <http://www.monitorware.com/Common/en/Articles/performance-optimizing-syslog-server.php>`_ diff --git a/source/tutorials/failover_syslog_server.rst b/source/tutorials/failover_syslog_server.rst new file mode 100644 index 0000000..32fc66c --- /dev/null +++ b/source/tutorials/failover_syslog_server.rst @@ -0,0 +1,72 @@ +********************** +Failover Syslog Server +********************** + + +There are often situations where syslog data from the local system should be +sent to a central syslogd (for consolidation, archival and whatever other +reasons). A common problem is that messages are lost when the central syslogd +goes down. +Rsyslog has the capability to work with failover servers to prevent message +loss. A prerequisite is that TCP based syslog or RELP forwarding is used to send +to the central server. The reason is that with UDP there is no reliable way to +detect the remote system has gone away. +Let's assume you have a primary and two secondary central servers. Then, you +can use the following config file excerpt to send data to them: + +.. code-block:: none + + if($msg contains "error") then { + action(type="omfwd" target="primary-syslog.example.com" port="10514" + protocol="tcp") + action(type="omfwd" target="secondary-1-syslog.example.com" port="10514" + action.execOnlyWhenPreviousIsSuspended="on") + action(type="omfwd" target="secondary-2-syslog.example.com" port="10514" + action.execOnlyWhenPreviousIsSuspended="on") + action(type="omfile" tag="failover" file="/var/log/localbuffer" + action.execOnlyWhenPreviousIsSuspended="on") + } + + +The action processes all messages that contain "error". It tries to forward +every message to primary-syslog.example.com (via tcp). If it can not reach that +server, it tries secondary-1-syslog.example.com, if that fails too, it tries +secondary-2-syslog.example.com. If neither of these servers can be connected, +the data is stored in /var/log/localbuffer. Please note that the secondaries +and the local log buffer are only used if the one before them does not work. +So ideally, /var/log/localbuffer will never receive a message. If one of the +servers resumes operation, it automatically takes over processing again. + +**Important:** Failover will **not** work when you define queues on the actions. +This is because a queue explicitely tells rsyslog that the action shall be +processed asynchronously. With asynchronous processing you do not have any +feedback capability. As such, the action will never fail. + +**If you would like to use a queue on the forwarding process as whole, the solution +is** to put all actions into a ruleset and assign a queue to the ruleset. In +that configuration, the ruleset is process asynchronously, but inside the +rule set each action is processed synchronously and can provide feedback, +which permits to detect failed actions. + +To do so, the above example can be rewritten as follows: + +.. code-block:: none + + ruleset(name="forwarding" queue.type="linkedList" queue.filename="fwdq") { + action(type="omfwd" target="primary-syslog.example.com" port="10514" + protocol="tcp") + action(type="omfwd" target="secondary-1-syslog.example.com" port="10514" + action.execOnlyWhenPreviousIsSuspended="on") + action(type="omfwd" target="secondary-2-syslog.example.com" port="10514" + action.execOnlyWhenPreviousIsSuspended="on") + action(type="omfile" tag="failover" file="/var/log/localbuffer" + action.execOnlyWhenPreviousIsSuspended="on") + } + + if($msg contains "error") then { + call forwarding + } + + +Please note that the example could also be rewritten in several other ways. To +keep things simple, we just provide one of those. diff --git a/source/tutorials/gelf_forwarding.rst b/source/tutorials/gelf_forwarding.rst new file mode 100644 index 0000000..21d9a0d --- /dev/null +++ b/source/tutorials/gelf_forwarding.rst @@ -0,0 +1,70 @@ +GELF forwarding in rsyslog +========================== + +*Written by Florian Riedl* + +Situation +--------- + +The current setup has a system with rsyslog as the central syslog server +and a system with Graylog for storage and analyzing the log messages. +Graylog expects the log messages to arrive in GELF (Graylog Extended Log +Format). + +Changing the default log format to GELF +--------------------------------------- + +To make rsyslog send GELF we basically need to create a custom template. +This template will define the format in which the log messages will get +sent to Graylog. + +:: + + template(name="gelf" type="list") { + constant(value="{\"version\":\"1.1\",") + constant(value="\"host\":\"") + property(name="hostname") + constant(value="\",\"short_message\":\"") + property(name="msg" format="json") + constant(value="\",\"timestamp\":") + property(name="timegenerated" dateformat="unixtimestamp") + constant(value=",\"level\":\"") + property(name="syslogseverity") + constant(value="\"}") + } + +This is a typical representation in the list format with all the necessary +fields and format definitions that Graylog expects. + +Applying the template to a syslog action +---------------------------------------- + +The next step is applying the template to our output action. Since we +are forwarding log messages to Graylog, this is usually a syslog sending +action. + +:: + + # syslog forwarder via UDP + action(type="omfwd" target="graylogserver" port="12201" protocol="udp" template="gelf") + +We now have a syslog forwarding action. This uses the omfwd module. Please +note that the case above only works for UDP transport. When using TCP, +Graylog expects a Nullbyte as message delimiter. So, to use TCP, you need to change delimiter via `TCP_FrameDelimiter <../configuration/modules/omfwd.html#tcp-framedelimiter>`_ option. + +:: + + # syslog forwarder via TCP + action(type="omfwd" target="graylogserver" port="12201" protocol="tcp" template="gelf" TCP_FrameDelimiter="0" KeepAlive="on") + +Conclusion +---------- + +With this quick and easy setup you can feed Graylog with the correct +log message format so it can do its work. This case can be applied to +a lot of different scenarios as well, but with different templates. + +This documentation is part of the `rsyslog <http://www.rsyslog.com/>`_ +project. + + diff --git a/source/tutorials/hash_sampling.rst b/source/tutorials/hash_sampling.rst new file mode 100644 index 0000000..4fe6ecf --- /dev/null +++ b/source/tutorials/hash_sampling.rst @@ -0,0 +1,82 @@ +Hash-based Sampling +=================== + + +Rsyslog supports various sampling mechanisms. These can be used on client systems to save servers from getting overwhelmed. Here we introduce a new sampling mechanism "Hash-based sampling". + +Let's consider the following setup of systems running services and generating logs. +There are three services A, B and C. +These services work together to create a request processing pipeline. +User request lands up at system A, which processes the request, generates logs and forwards it to service B. +B processes the request it received from A, generates logs and forwards it to C and so on and so forth. + +:: + + +-+-+-+-+-+-+ +-+ +-+ +-+ +-+-++-+-+ + |UserRequest| -> |A| -> |B| -> |C| -> | Database | + +-+-+-+-+-+-+ +-+ +-+ +-+ +-+-++-+-+ + + +Consider three sample user requests + :: + + {"request_id": "reqid1", "data": "payload_1_original"} + {"request_id": "reqid2", "data": "payload_2_original"} + {"request_id": "reqid3", "data": "payload_3_original"} + +Service A generated logs + :: + + {"request_id": "reqid1", "datetime": "<time>", "Processing_state" : "A", "Exception" : "none"} + {"request_id": "reqid2", "datetime": "<time>", "Processing_state" : "A_prime", "Exception" : "Unknown flow"} + {"request_id": "reqid3", "datetime": "<time>", "Processing_state" : "A_double_prime", "Exception" : "Parsing Failed"} + +Service B generated logs + :: + + {"request_id": "reqid1", "datetime": "<time>", "Processing_state" : "B", "Exception" : "none"} + {"request_id": "reqid2", "datetime": "<time>", "Processing_state" : "A_Failed_at_1st_Stage", "Exception" : "none"} + {"request_id": "reqid3", "datetime": "<time>", "Processing_state" : "B_Failed", "Exception" : "Field not found"} + +Service C generated logs + :: + + {"request_id": "reqid1", "datetime": "<time>", "Processing_state" : "C", "Exception" : "none"} + {"request_id": "reqid2", "datetime": "<time>", "Processing_state" : "NO_OP", "Exception" : "none"} + {"request_id": "reqid3", "datetime": "<time>", "Processing_state" : "C_Failed", "Exception" : "NullPointer"} + + +We can sample logs based on request_id thereby getting **all-or-none** logs associated with a request_id. This is a kind of transactional guarantee on logs for a request ID. This helps to create an end to end picture of pipeline even on sampled data. + +Using hash64mod for sampling + :: + + if (hash64mod($!msg!request_id, 100) <= 30) then { + //send out + } + +With hash64mod sampling, we get sampled logs like + :: + + {"request_id": "reqid3", "data": "payload_3_original"} + {"request_id": "reqid3", "datetime": "<time>", "Processing_state" : "A_double_prime", "Exception" : "Parsing Failed"} + {"request_id": "reqid3", "datetime": "<time>", "Processing_state" : "B_Failed", "Exception" : "Field not found"} + {"request_id": "reqid3", "datetime": "<time>", "Processing_state" : "C_Failed", "Exception" : "NullPointer"} + +We will get all-or-none logs associated to hash-string (request ID in this case or combination of field_1 & field_2 & field_3) giving a full view of a request's life cycle in the cluster across various systems. The only constraint in hash-based sampling is, it will work only if we have the same unique identifier (single field or combination of fields) in logs across services. + +Same as hash64mod, we can use hash64 to add hash as tags that can be used later to filter logs. + +Using hash64 for filtering later + :: + + set $.hash = hash64($!msg!field_1 & $!msg!field_2 & $!msg!field_3) + set $!tag= $syslogtag & $.hash; + //send out + +Hash-based sampling is helpful on a single system too. Say a single process generates 4 log lines for each transaction it commits. We can get all-or-none guarantees around these 4 logs generated for each transaction. Thereby giving a complete picture of a transaction (while sampling). + +**Note** + * Hash-based sampling can be used only when logs have **same unique identifier** across services. + * Default hash implementation is djb2 hash and xxhash can be enabled using compile-time flag (hash implementation can change release to release, check changelog). + * For parsing log to generate json to act on individual fields use mmnormalize. diff --git a/source/tutorials/high_database_rate.rst b/source/tutorials/high_database_rate.rst new file mode 100644 index 0000000..6189943 --- /dev/null +++ b/source/tutorials/high_database_rate.rst @@ -0,0 +1,161 @@ +Handling a massive syslog database insert rate with Rsyslog +=========================================================== + +*Written by* `Rainer Gerhards <http://www.gerhards.net/rainer>`_ +*(2008-01-31)* + +Abstract +-------- + +**In this paper, I describe how log massive amounts of** +`syslog <http://www.monitorware.com/en/topics/syslog/>`_ **messages to a +database.**\ This HOWTO is currently under development and thus a bit +brief. Updates are promised ;).* + +The Intention +------------- + +Database updates are inherently slow when it comes to storing syslog +messages. However, there are a number of applications where it is handy +to have the message inside a database. Rsyslog supports native database +writing via output plugins. As of this writing, there are plugins +available for MySQL an PostgreSQL. Maybe additional plugins have become +available by the time you read this. Be sure to check. + +In order to successfully write messages to a database backend, the +backend must be capable to record messages at the expected average +arrival rate. This is the rate if you take all messages that can arrive +within a day and divide it by 86400 (the number of seconds per day). +Let's say you expect 43,200,000 messages per day. That's an average rate +of 500 messages per second (mps). Your database server MUST be able to +handle that amount of message per second on a sustained rate. If it +doesn't, you either need to add an additional server, lower the number +of message - or forget about it. + +However, this is probably not your peak rate. Let's simply assume your +systems work only half a day, that's 12 hours (and, yes, I know this is +unrealistic, but you'll get the point soon). So your average rate is +actually 1,000 mps during work hours and 0 mps during non-work hours. To +make matters worse, workload is not divided evenly during the day. So +you may have peaks of up to 10,000mps while at other times the load may +go down to maybe just 100mps. Peaks may stay well above 2,000mps for a +few minutes. + +So how the hack you will be able to handle all of this traffic +(including the peaks) with a database server that is just capable of +inserting a maximum of 500mps? + +The key here is buffering. Messages that the database server is not +capable to handle will be buffered until it is. Of course, that means +database insert are NOT real-time. If you need real-time inserts, you +need to make sure your database server can handle traffic at the actual +peak rate. But lets assume you are OK with some delay. + +Buffering is fine. But how about these massive amounts of data? That +can't be hold in memory, so don't we run out of luck with buffering? The +key here is that rsyslog can not only buffer in memory but also buffer +to disk (this may remind you of "spooling" which gets you the right +idea). There are several queuing modes available, offering different +throughput. In general, the idea is to buffer in memory until the memory +buffer is exhausted and switch to disk-buffering when needed (and only +as long as needed). All of this is handled automatically and +transparently by rsyslog. + +With our above scenario, the disk buffer would build up during the day +and rsyslog would use the night to drain it. Obviously, this is an +extreme example, but it shows what can be done. Please note that queue +content survies rsyslogd restarts, so even a reboot of the system will +not cause any message loss. + +How To Setup +------------ + +Frankly, it's quite easy. You just need to do is instruct rsyslog to use +a disk queue and then configure your action. There is nothing else to +do. With the following simple config file, you log anything you receive +to a MySQL database and have buffering applied automatically. + +:: + + module(load="imuxsock") # provides support for local system logging + + # provides UDP syslog reception + module(load="imudp") + input(type="imudp" port="514") + + # Make sure this path exists and the user of the deamon has read/write/execute access + global(WorkDirectory="/var/spool/rsyslog") # default location for work (spool) files + main_queue(queue.fileName="mainq") + + *.* action(type="ommysql" server="<hostname>" db="Syslog" uid="<database user name>" pwd="<database user password>" + action.resumeRetryCount="-1") + # for PostgreSQL replace :ommysql: by :ompgsql: below: *.* :ommysql:hostname,dbname,userid,password; + +The simple setup above has one drawback: the write database action is +executed together with all other actions. Typically, local files are +also written. These local file writes are now bound to the speed of the +database action. So if the database is down, or there is a large +backlog, local files are also not (or late) written. + +**There is an easy way to avoid this with rsyslog.** It involves a +slightly more complicated setup. In rsyslog, each action can utilize its +own queue. If so, messages are simply pulled over from the main queue +and then the action queue handles action processing on its own. This +way, main processing and the action are de-coupled. In the above +example, this means that local file writes will happen immediately while +the database writes are queued. As a side-note, each action can have its +own queue, so if you would like to more than a single database or send +messages reliably to another host, you can do all of this on their own +queues, de-coupling their processing speeds. + +The configuration for the de-coupled database write involves just a few +more commands: + +:: + + module(load="imuxsock") # provides support for local system logging + + # provides UDP syslog reception + module(load="imudp") + input(type="imudp" port="514") + + # Make sure this path exists and the user of the deamon has read/write/execute access + global(WorkDirectory="/var/spool/rsyslog") # default location for work (spool) files + + module (load="ommysql") + *.* action(type="ommysql" server="<hostname>" db="Syslog" uid="<database user name>" pwd="<database user password>" + queue.filename="databasequeue" action.resumeRetryCount="-1") + ) + +**This is the recommended configuration for this use case.** It requires +rsyslog 8.1908.0 or above. + +In this example, the main message queue is NOT disk-assisted (there is +no main_queue() object). We still could do that, but have +not done it because there seems to be no need. The only slow running +action is the database writer and it has its own queue. So there is no +real reason to use a large main message queue (except, of course, if you +expect \*really\* heavy traffic bursts). + +Note that you can modify a lot of queue performance parameters, but the +above config will get you going with default values. If you consider +using this on a real busy server, it is strongly recommended to invest +some time in setting the tuning parameters to appropriate values. + +Feedback requested +~~~~~~~~~~~~~~~~~~ + +I would appreciate feedback on this tutorial. If you have additional +ideas, comments or find bugs (I \*do\* bugs - no way... ;)), please `let +me know <mailto:rgerhards@adiscon.com>`_. + +Revision History +---------------- + +- 2008-01-28 \* `Rainer Gerhards`_ \* + Initial Version created +- 2008-01-28 \* `Rainer Gerhards`_ \* + Updated to new v3.11.0 capabilities +- 2021-04-21 \* Stev Leibelt \* + Updated configuration section to non legacy format + diff --git a/source/tutorials/index.rst b/source/tutorials/index.rst new file mode 100644 index 0000000..8a97d96 --- /dev/null +++ b/source/tutorials/index.rst @@ -0,0 +1,18 @@ +Tutorials +========= + +.. toctree:: + :maxdepth: 2 + + tls_cert_summary + tls + database + high_database_rate + reliable_forwarding + recording_pri + failover_syslog_server + log_rotation_fix_size + gelf_forwarding + log_sampling + random_sampling + hash_sampling diff --git a/source/tutorials/log_rotation_fix_size.rst b/source/tutorials/log_rotation_fix_size.rst new file mode 100644 index 0000000..d2d1570 --- /dev/null +++ b/source/tutorials/log_rotation_fix_size.rst @@ -0,0 +1,60 @@ +Log rotation with rsyslog +========================= + +*Written by Michael Meckelein* + +Situation +--------- + +Your environment does not allow you to store tons of logs? You have +limited disc space available for logging, for example you want to log to +a 124 MB RAM usb stick? Or you do not want to keep all the logs for +months, logs from the last days is sufficient? Think about log rotation. + +Log rotation based on a fixed log size +-------------------------------------- + +This small but hopefully useful article will show you the way to keep +your logs at a given size. The following sample is based on rsyslog +illustrating a simple but effective log rotation with a maximum size +condition. + +Use Output Channels for fixed-length syslog files +------------------------------------------------- + +Lets assume you do not want to spend more than 100 MB hard disc space +for you logs. With rsyslog you can configure Output Channels to achieve +this. Putting the following directive + +:: + + # start log rotation via outchannel + # outchannel definition + $outchannel log_rotation,/var/log/log_rotation.log, 52428800,/home/me/./log_rotation_script + # activate the channel and log everything to it + *.* :omfile:$log_rotation + # end log rotation via outchannel + +to rsyslog.conf instruct rsyslog to log everything to the destination +file '/var/log/log\_rotation.log' until the give file size of 50 MB is +reached. If the max file size is reached it will perform an action. In +our case it executes the script /home/me/log\_rotation\_script which +contains a single command: + +:: + + mv -f /var/log/log_rotation.log /var/log/log_rotation.log.1 + +This moves the original log to a kind of backup log file. After the +action was successfully performed rsyslog creates a new +/var/log/log\_rotation.log file and fill it up with new logs. So the +latest logs are always in log\_rotation.log. + +Conclusion +---------- + +With this approach two files for logging are used, each with a maximum +size of 50 MB. So we can say we have successfully configured a log +rotation which satisfies our requirement. We keep the logs at a +fixed-size level of 100 MB. + diff --git a/source/tutorials/log_sampling.rst b/source/tutorials/log_sampling.rst new file mode 100644 index 0000000..c8b9ddb --- /dev/null +++ b/source/tutorials/log_sampling.rst @@ -0,0 +1,13 @@ +Log Sampling +============ + +Rsyslog supports various sampling mechanism. +User can perform sampling while collecting logs from client systems and forward it to server systems for aggregation and persistence. + +Sampling strategies +------------------- + +Rsyslog support following sampling strategies:- + + - :doc:`Random sampling<./random_sampling>` + - :doc:`Hash based sampling<./hash_sampling>` diff --git a/source/tutorials/random_sampling.rst b/source/tutorials/random_sampling.rst new file mode 100644 index 0000000..3c7d5d3 --- /dev/null +++ b/source/tutorials/random_sampling.rst @@ -0,0 +1,16 @@ +Random sampling +=============== + +Rsyslog supports various sampling mechanisms. These can be used on client systems to save servers from getting overwhelmed. Here we introduce a new sampling mechanism "Random sampling". + +Let's consider a system that is generating logs at rate of 100 logs/sec. +If we want to get 20% of these logs uniformly sampled we use random sampling. + +.. code-block:: none + + set $.rand = random(100); + if ($.rand <= 20) then { + //send out + } + +Above config will collect 20% of logs generated. diff --git a/source/tutorials/recording_pri.rst b/source/tutorials/recording_pri.rst new file mode 100644 index 0000000..8ad0cfe --- /dev/null +++ b/source/tutorials/recording_pri.rst @@ -0,0 +1,141 @@ +Recording the Priority of Syslog Messages +========================================= + +*Written by* `Rainer Gerhards <https://rainer.gerhards.net>`_ *(2007-06-18)* + +Abstract +-------- + +**The so-called priority (PRI) is very important in syslog messages, +because almost all filtering in syslog.conf is based on it.** However, +many syslogds (including the Linux stock sysklogd) do not provide a way +to record that value. In this article, I'll give a brief overview of how +PRI can be written to a log file. + +Background +---------- + +The PRI value is a combination of so-called severity and facility. The +facility indicates where the message originated from (e.g. kernel, mail +subsystem) while the severity provides a glimpse of how important the +message might be (e.g. error or informational). Be careful with these +values: they are in no way consistent across applications (especially +severity). However, they still form the basis of most filtering in +syslog.conf. For example, the directive (aka "selector line) + +:: + + mail.* /var/log/mail.log + +means that messages with the mail facility should be stored to +/var/log/mail.log, no matter which severity indicator they have (that is +telling us the asterisk). If you set up complex conditions, it can be +annoying to find out which PRI value a specific syslog message has. Most +stock syslogds do not provide any way to record them. + +How is it done? +--------------- + +With `rsyslog <http://www.rsyslog.com/>`_, PRI recording is simple. All +you need is the correct template. Even if you do not use rsyslog on a +regular basis, it might be a handy tool for finding out the priority. + +Rsyslog provides a flexible system to specify the output formats. It is +template-based. A template with the traditional syslog format looks as +follows: + +:: + + $template TraditionalFormat,"%timegenerated% %HOSTNAME% %syslogtag%%msg:::drop-last-lf%\n" + +The part in quotes is the output formats. Things between percent-signs +are so-called `messages properties <property_replacer.html>`_. They are +replaced with the respective content from the syslog message when output +is written. Everything outside of the percent signs is literal text, +which is simply written as specified. + +Thankfully, rsyslog provides message properties for the priority. These +are called "PRI", "syslogfacility" and "syslogpriority" (case is +important!). They are numerical values. Starting with rsyslog 1.13.4, +there is also a property "pri-text", which contains the priority in +friendly text format (e.g. "local0.err<133>"). For the rest of this +article, I assume that you run version 1.13.4 or higher. + +Recording the priority is now a simple matter of adding the respective +field to the template. It now looks like this: + +:: + + $template TraditionalFormatWithPRI,"%pri-text%: %timegenerated% %HOSTNAME% %syslogtag%%msg:::drop-last-lf%\n" + +Now we have the right template - but how to write it to a file? You +probably have a line like this in your syslog.conf: + +:: + + *.* -/var/log/messages.log + +It does not specify a template. Consequently, rsyslog uses the +traditional format. In order to use some other format, simply specify +the template after the semicolon: + +:: + + *.* -/var/log/messages.log;TraditionalFormatWithPRI + +That's all you need to do. There is one common pitfall: you need to +define the template before you use it in a selector line. Otherwise, you +will receive an error. + +Once you have applied the changes, you need to restart rsyslogd. It will +then pick the new configuration. + +What if I do not want rsyslogd to be the standard syslogd? +---------------------------------------------------------- + +If you do not want to switch to rsyslog, you can still use it as a setup +aid. A little bit of configuration is required. + +#. Download, make and install rsyslog +#. copy your syslog.conf over to rsyslog.conf +#. add the template described above to it; select the file that should + use it +#. stop your regular syslog daemon for the time being +#. run rsyslogd (you may even do this interactively by calling it with + the -n additional option from a shell) +#. stop rsyslogd (press ctrl-c when running interactively) +#. restart your regular syslogd + +That's it - you can now review the priorities. + +Some Sample Data +---------------- + +Below is some sample data created with the template specified above. +Note the priority recording at the start of each line. + +:: + + kern.info<6>: Jun 15 18:10:38 host kernel: PCI: Sharing IRQ 11 with 00:04.0 + kern.info<6>: Jun 15 18:10:38 host kernel: PCI: Sharing IRQ 11 with 01:00.0 + kern.warn<4>: Jun 15 18:10:38 host kernel: Yenta IRQ list 06b8, PCI irq11 + kern.warn<4>: Jun 15 18:10:38 host kernel: Socket status: 30000006 + kern.warn<4>: Jun 15 18:10:38 host kernel: Yenta IRQ list 06b8, PCI irq11 + kern.warn<4>: Jun 15 18:10:38 host kernel: Socket status: 30000010 + kern.info<6>: Jun 15 18:10:38 host kernel: cs: IO port probe 0x0c00-0x0cff: clean. + kern.info<6>: Jun 15 18:10:38 host kernel: cs: IO port probe 0x0100-0x04ff: excluding 0x100-0x107 0x378-0x37f 0x4d0-0x4d7 + kern.info<6>: Jun 15 18:10:38 host kernel: cs: IO port probe 0x0a00-0x0aff: clean. + local7.notice<189>: Jun 15 18:17:24 host dd: 1+0 records out + local7.notice<189>: Jun 15 18:17:24 host random: Saving random seed: succeeded + local7.notice<189>: Jun 15 18:17:25 host portmap: portmap shutdown succeeded + local7.notice<189>: Jun 15 18:17:25 host network: Shutting down interface eth1: succeeded + local7.notice<189>: Jun 15 18:17:25 host network: Shutting down loopback interface: succeeded + local7.notice<189>: Jun 15 18:17:25 host pcmcia: Shutting down PCMCIA services: cardmgr + user.notice<13>: Jun 15 18:17:25 host /etc/hotplug/net.agent: NET unregister event not supported + local7.notice<189>: Jun 15 18:17:27 host pcmcia: modules. + local7.notice<189>: Jun 15 18:17:29 host rc: Stopping pcmcia: succeeded + local7.notice<189>: Jun 15 18:17:30 host rc: Starting killall: succeeded + syslog.info<46>: Jun 15 18:17:33 host [origin software="rsyslogd" swVersion="1.13.3" x-pid="2464"] exiting on signal 15. + syslog.info<46>: Jun 18 10:55:47 host [origin software="rsyslogd" swVersion="1.13.3" x-pid="2367"][x-configInfo udpReception="Yes" udpPort="514" tcpReception="Yes" tcpPort="1470"] restart + user.notice<13>: Jun 18 10:55:50 host rger: test + syslog.info<46>: Jun 18 10:55:52 host [origin software="rsyslogd" swVersion="1.13.3" x-pid="2367"] exiting on signal 2.`` diff --git a/source/tutorials/reliable_forwarding.rst b/source/tutorials/reliable_forwarding.rst new file mode 100644 index 0000000..a434ff1 --- /dev/null +++ b/source/tutorials/reliable_forwarding.rst @@ -0,0 +1,171 @@ +Reliable Forwarding of syslog Messages with Rsyslog +=================================================== + +*Written by* `Rainer Gerhards <https://rainer.gerhards.net/>`_ +*(2008-06-27)* + +Abstract +-------- + +**In this paper, I describe how to forward** +`syslog <http://www.monitorware.com/en/topics/syslog/>`_ **messages +(quite) reliable to a central rsyslog server.** This depends on rsyslog +being installed on the client system and it is recommended to have it +installed on the server system. Please note that industry-standard +`plain TCP syslog protocol is not fully +reliable <https://rainer.gerhards.net/2008/04/on-unreliability-of-plain-tcp-syslog.html>`_ +(thus the "quite reliable"). If you need a truly reliable solution, you +need to look into RELP (natively supported by rsyslog).* + +The Intention +------------- + +Whenever two systems talk over a network, something can go wrong. For +example, the communications link may go down, or a client or server may +abort. Even in regular cases, the server may be offline for a short +period of time because of routine maintenance. + +A logging system should be capable of avoiding message loss in +situations where the server is not reachable. To do so, unsent data +needs to be buffered at the client while the server is offline. Then, +once the server is up again, this data is to be sent. + +This can easily be accomplished by rsyslog. In rsyslog, every action runs +on its own queue and each queue can be set to buffer data if the action +is not ready. Of course, you must be able to detect that "the action is +not ready", which means the remote server is offline. This can be +detected with plain TCP syslog and RELP, but not with UDP. So you need +to use either of the two. In this howto, we use plain TCP syslog. + +Please note that we are using rsyslog-specific features. They are +required on the client, but not on the server. So the client system must +run rsyslog (at least version 3.12.0), while on the server another +syslogd may be running, as long as it supports plain tcp syslog. + +**The rsyslog queueing subsystem tries to buffer to memory. So even if +the remote server goes offline, no disk file is generated.** File on +disk are created only if there is need to, for example if rsyslog runs +out of (configured) memory queue space or needs to shutdown (and thus +persist yet unsent messages). Using main memory and going to the disk +when needed is a huge performance benefit. You do not need to care about +it, because, all of it is handled automatically and transparently by +rsyslog. + +How To Setup +------------ + +First, you need to create a working directory for rsyslog. This is where +it stores its queue files (should need arise). You may use any location +on your local system. + +Next, you need to instruct rsyslog to use a disk queue and then +configure your action. There is nothing else to do. With the following +simple config file, you forward anything you receive to a remote server +and have buffering applied automatically when it goes down. This must be +done on the client machine. + +.. code-block:: linux-config + + $ModLoad imuxsock # local message reception + $WorkDirectory /rsyslog/work # default location for work (spool) files + $ActionQueueType LinkedList # use asynchronous processing + $ActionQueueFileName srvrfwd # set file name, also enables disk mode + $ActionResumeRetryCount -1 # infinite retries on insert failure + $ActionQueueSaveOnShutdown on # save in-memory data if rsyslog shuts down + *.* @@server:port + +The port given above is optional. It may not be specified, in which case +you only provide the server name. The "$ActionQueueFileName" is used to +create queue files, should need arise. This value must be unique inside +rsyslog.conf. No two rules must use the same queue file. Also, for +obvious reasons, it must only contain those characters that can be used +inside a valid file name. Rsyslog possibly adds some characters in front +and/or at the end of that name when it creates files. So that name +should not be at the file size name length limit (which should not be a +problem these days). + +Please note that actual spool files are only created if the remote +server is down **and** there is no more space in the in-memory queue. By +default, a short failure of the remote server will never result in the +creation of a disk file as a couple of hundred messages can be held in +memory by default. [These parameters can be fine-tuned. However, then +you need to either fully understand how the queue works (`read elaborate +doc <http://www.rsyslog.com/doc-queues.html>`_) or use `professional +services <http://www.rsyslog.com/professional-services/>`_ to +have it done based on your specs ;) - what that means is that +fine-tuning queue parameters is far from being trivial...] + +If you would like to test if your buffering scenario works, you need to +stop, wait a while and restart your central server. Do **not** watch for +files being created, as this usually does not happen and never happens +immediately. + +Forwarding to More than One Server +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +If you have more than one server you would like to forward to, that's +quickly done. Rsyslog has no limit on the number or type of actions, so +you can define as many targets as you like. What is important to know, +however, is that the full set of directives make up an action. So you +can not simply add (just) a second forwarding rule, but need to +duplicate the rule configuration as well. Be careful that you use +different queue file names for the second action, else you will mess up +your system. + +A sample for forwarding to two hosts looks like this: + +.. code-block:: linux-config + + $ModLoad imuxsock # local message reception + $WorkDirectory /rsyslog/work # default location for work (spool) files + + # start forwarding rule 1 + $ActionQueueType LinkedList # use asynchronous processing + $ActionQueueFileName srvrfwd1 # set file name, also enables disk mode + $ActionResumeRetryCount -1 # infinite retries on insert failure + $ActionQueueSaveOnShutdown on # save in-memory data if rsyslog shuts down + *.* @@server1:port + # end forwarding rule 1 + + # start forwarding rule 2 + $ActionQueueType LinkedList # use asynchronous processing + $ActionQueueFileName srvrfwd2 # set file name, also enables disk mode + $ActionResumeRetryCount -1 # infinite retries on insert failure + $ActionQueueSaveOnShutdown on # save in-memory data if rsyslog shuts down + *.* @@server2 + # end forwarding rule 2 + +Note the filename used for the first rule it is "srvrfwd1" and for the +second it is "srvrfwd2". I have used a server without port name in the +second forwarding rule. This was just to illustrate how this can be +done. You can also specify a port there (or drop the port from server1). + +When there are multiple action queues, they all work independently. +Thus, if server1 goes down, server2 still receives data in real-time. +The client will **not** block and wait for server1 to come back online. +Similarly, server1's operation will not be affected by server2's state. + +Some Final Words on Reliability ... +----------------------------------- + +Using plain TCP syslog provides a lot of reliability over UDP syslog. +However, plain TCP syslog is **not** a fully reliable transport. In +order to get full reliability, you need to use the RELP protocol. + +Follow the next link to learn more about `the problems you may encounter +with plain tcp +syslog <https://rainer.gerhards.net/2008/04/on-unreliability-of-plain-tcp-syslog.html>`_. + +Feedback requested +~~~~~~~~~~~~~~~~~~ + +I would appreciate feedback on this tutorial. If you have additional +ideas, comments or find bugs (I \*do\* bugs - no way... ;)), please `let +me know <mailto:rgerhards@adiscon.com>`_. + +Revision History +---------------- + +- 2008-06-27 \* `Rainer Gerhards <https://rainer.gerhards.net/>`_ \* + Initial Version created + diff --git a/source/tutorials/tls.rst b/source/tutorials/tls.rst new file mode 100644 index 0000000..54a07d9 --- /dev/null +++ b/source/tutorials/tls.rst @@ -0,0 +1,335 @@ +Encrypting Syslog Traffic with TLS (SSL) [short version] +======================================================== + +*Written by* `Rainer Gerhards <http://www.gerhards.net/rainer>`_ +*(2008-05-06)* + +Abstract +-------- + +**In this paper, I describe how to encrypt** +`syslog <http://www.monitorware.com/en/topics/syslog/>`_ +**messages on the network.** +Encryption is vital to keep the confidential content of +syslog messages secure. I describe the overall approach and provide an +HOWTO do it with `rsyslog's <http://www.rsyslog.com>`_ TLS features. + +Please note that TLS is the more secure successor of SSL. While people +often talk about "SSL encryption" they actually mean "TLS encryption". +So don't look any further if you look for how to SSL-encrypt syslog. You +have found the right spot. + +This is a quick guide. There is a more elaborate guide currently under +construction which provides a much more secure environment. It is highly +recommended to `at least have a look at it <rsyslog_secure_tls.html>`_. + +Background +---------- + +**Traditional syslog is a clear-text protocol. That means anyone with a +sniffer can have a peek at your data.** In some environments, this is no +problem at all. In others, it is a huge setback, probably even +preventing deployment of syslog solutions. Thankfully, there are easy +ways to encrypt syslog communication. + +The traditional approach involves `running a wrapper like stunnel around +the syslog session <rsyslog_stunnel.html>`_. This works quite well and +is in widespread use. However, it is not tightly coupled with the main +syslogd and some, even severe, problems can result from this (follow a +mailing list thread that describes `total loss of syslog messages due to +stunnel +mode <http://lists.adiscon.net/pipermail/rsyslog/2008-March/000580.html>`_ +and the `unreliability of TCP +syslog <http://rgerhards.blogspot.com/2008/04/on-unreliability-of-plain-tcp-syslog.html>`_). + +`Rsyslog supports syslog via GSSAP <gssapi.html>`_\ I since long to +overcome these limitations. However, syslog via GSSAPI is a +rsyslog-exclusive transfer mode and it requires a proper Kerberos +environment. As such, it isn't a really universal solution. The +`IETF <http://www.ietf.org/>`_ has begun standardizing syslog over plain +tcp over TLS for a while now. While I am not fully satisfied with the +results so far, this obviously has the potential to become the +long-term solution. The Internet Draft in question, syslog-transport-tls +has been dormant for some time but is now (May of 2008) again being +worked on. I expect it to turn into a RFC within the next 12 month (but +don't take this for granted ;)). I didn't want to wait for it, because +there obviously is need for TLS syslog right now (and, honestly, I have +waited long enough...). Consequently, I have implemented the current +draft, with some interpretations I made (there will be a compliance doc +soon). So in essence, a TLS-protected syslog transfer mode is available +right now. As a side-note, Rsyslog is the world's first implementation +of syslog-transport-tls. + +Please note that in theory it should be compatible with other, non IETF +syslog-transport-tls implementations. If you would like to run it with +something else, please let us know so that we can create a compatibility +list (and implement compatibility where it doesn't yet exist). + +Overall System Setup +-------------------- + +Encryption requires a reliable stream. So It will not work over UDP +syslog. In rsyslog, network transports utilize a so-called "network +stream layer" (netstream for short). This layer provides a unified view +of the transport to the application layer. The plain TCP syslog sender +and receiver are the upper layer. The driver layer currently consists of +the "ptcp" and "gtls" library plugins. "ptcp" stands for "plain tcp" and +is used for unencrypted message transfer. It is also used internally by +the gtls driver, so it must always be present on a system. The "gtls" +driver is for GnutTLS, a TLS library. It is used for encrypted message +transfer. In the future, additional drivers will become available (most +importantly, we would like to include a driver for NSS). + +What you need to do to build an encrypted syslog channel is to simply +use the proper netstream drivers on both the client and the server. +Client, in the sense of this document, is the rsyslog system that is +sending syslog messages to a remote (central) loghost, which is called +the server. In short, the setup is as follows: + +**Client** + +- forwards messages via plain tcp syslog using gtls netstream driver to + central server on port 6514 + +**Server** + +- accept incoming messages via plain tcp syslog using gtls netstream + driver on port 6514 + +Setting up the system +--------------------- + +Server Setup +~~~~~~~~~~~~ + +At the server, you need to have a digital certificate. That certificate +enables SSL operation, as it provides the necessary crypto keys being +used to secure the connection. There is a set of default certificates in +./contrib/gnutls. These are key.pem and cert.pem. These are good for +testing. If you use it in production, it is very easy to break into your +secure channel as everybody is able to get hold of your private key. So +it is a good idea to generate the key and certificate yourself. + +You also need a root CA certificate. Again, there is a sample CA +certificate in ./contrib/gnutls, named ca.cert. It is suggested to +generate your own. + +To configure the server, you need to tell it where are its certificate +files, to use the gtls driver and start up a listener. This is done as +follows: + + :: + + # make gtls driver the default and set certificate files + global( + DefaultNetstreamDriver="gtls" + DefaultNetstreamDriverCAFile="/path/to/contrib/gnutls/ca.pem" + DefaultNetstreamDriverCertFile="/path/to/contrib/gnutls/cert.pem" + DefaultNetstreamDriverKeyFile="/path/to/contrib/gnutls/key.pem" + ) + + # load TCP listener + module( + load="imtcp" + StreamDriver.Name="gtls" + StreamDriver.Mode="1" + StreamDriver.Authmode="anon" + ) + + # start up listener at port 6514 + input( + type="imtcp" + port="6514" + ) + +This is all you need to do. You can use the rest of your rsyslog.conf +together with this configuration. The way messages are received does not +interfere with any other option, so you are able to do anything else you +like without any restrictions. + +Restart rsyslogd. The server should now be fully operational. + +Client Setup +~~~~~~~~~~~~ + +The client setup is equally simple. You need less certificates, just the +CA cert. + + :: + + # certificate files - just CA for a client + global(DefaultNetstreamDriverCAFile="/path/to/contrib/gnutls/ca.pem") + + # set up the action for all messages + action(type="omfwd" protocol="tcp" target="s.example.net" port="6514" + StreamDriver="gtls" StreamDriverMode="1" StreamDriverAuthMode="anon") + +Note that we use the regular TCP forwarding action here. There is +nothing special, because the encryption is handled by the netstream +driver. So I have just forwarded every message (\*.\*) for simplicity - +you can use any of rsyslog's filtering capabilities (like +expression-based filters or regular expressions). + +Done +~~~~ + +After following these steps, you should have a working secure syslog +forwarding system. To verify, you can type "logger test" or a similar +"smart" command on the client. It should show up in the respective +server log file. If you dig out your sniffer, you should see that the +traffic on the wire is actually protected. + +Certificates +------------ + +In order to be really secure, certificates are needed. This is a short +summary on how to generate the necessary certificates with GnuTLS' +certtool. You can also generate certificates via other tools, but as we +currently support GnuTLS as the only TLS library, we thought it is a +good idea to use their tools. + +Note that this section aims at people who are not involved with PKI at +all. The main goal is to get them going in a reasonable secure way. + +CA Certificate +~~~~~~~~~~~~~~ + +This is used to sign all of your other certificates. The CA cert must be +trusted by all clients and servers. The private key must be +well-protected and not given to any third parties. The certificate +itself can (and must) be distributed. To generate it, do the following: + +#. generate the private key: + + :: + + certtool --generate-privkey --outfile ca-key.pem + + This takes a short while. Be sure to do some work on your + workstation, it waits for random input. Switching between windows is + sufficient ;) + +#. now create the (self-signed) CA certificate itself: + + :: + + certtool --generate-self-signed --load-privkey ca-key.pem --outfile ca.pem + + This generates the CA certificate. This command queries you for a + number of things. Use appropriate responses. When it comes to + certificate validity, keep in mind that you need to recreate all + certificates when this one expires. So it may be a good idea to use a + long period, eg. 3650 days (roughly 10 years). You need to specify + that the certificates belongs to an authority. The certificate is used + to sign other certificates. + +#. You need to distribute this certificate to all peers and you need to + point to it via the $DefaultNetstreamDriverCAFile config directive. + All other certificates will be issued by this CA. + Important: do only distribute the ca.pem, NOT ca-key.pem (the + private key). Distributing the CA private key would totally breach + security as everybody could issue new certificates on the behalf of + this CA. + +Individual Peer Certificate +~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +Each peer (be it client, server or both), needs a certificate that +conveys its identity. Access control is based on these certificates. You +can, for example, configure a server to accept connections only from +configured clients. The client ID is taken from the client instances +certificate. So as a general rule of thumb, you need to create a +certificate for each instance of rsyslogd that you run. That instance +also needs the private key, so that it can properly decrypt the traffic. +Safeguard the peer's private key file. If somebody gets hold of it, it +can maliciously pretend to be the compromised host. If such happens, +regenerate the certificate and make sure you use a different name +instead of the compromised one (if you use name-based authentication). + +These are the steps to generate the individual certificates (repeat: you +need to do this for every instance, do NOT share the certificates +created in this step): + +#. generate a private key (do NOT mistake this with the CA's private key + - this one is different): + + :: + + certtool --generate-privkey --outfile key.pem + + Again, this takes a short while. + +#. generate a certificate request: + + :: + + certtool --generate-request --load-privkey key.pem --outfile request.pem + + If you do not have the CA's private key (because you are not + authorized for this), you can send the certificate request to the + responsible person. If you do this, you can skip the remaining steps, + as the CA will provide you with the final certificate. If you submit + the request to the CA, you need to tell the CA the answers that you + would normally provide in step 3 below. + +#. Sign (validate, authorize) the certificate request and generate the + instances certificate. You need to have the CA's certificate and + private key for this: + + :: + + certtool --generate-certificate --load-request request.pem --outfile cert.pem \ --load-ca-certificate ca.pem --load-ca-privkey ca-key.pem + + Answer questions as follows: Cert does not belong to an authority; it + is a TLS web server and client certificate; the dnsName MUST be the + name of the peer in question (e.g. centralserver.example.net) - this + is the name used for authenticating the peers. Please note that you + may use an IP address in dnsName. This is a good idea if you would + like to use default server authentication and you use selector lines + with IP addresses (e.g. "\*.\* @@192.168.0.1") - in that case you + need to select a dnsName of 192.168.0.1. But, of course, changing the + server IP then requires generating a new certificate. + +After you have generated the certificate, you need to place it onto the +local machine running rsyslogd. Specify the certificate and key via the +$DefaultNetstreamDriverCertFile /path/to/cert.pem and +$DefaultNetstreamDriverKeyFile /path/to/key.pem configuration +directives. Make sure that nobody has access to key.pem, as that would +breach security. And, once again: do NOT use these files on more than +one instance. Doing so would prevent you from distinguishing between the +instances and thus would disable useful authentication. + +Troubleshooting Certificates +~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +If you experience trouble with your certificate setup, it may be useful +to get some information on what is contained in a specific certificate +(file). To obtain that information, do + +:: + + $ certtool --certificate-info --infile cert.pem + +where "cert.pem" can be replaced by the various certificate pem files +(but it does not work with the key files). + +Conclusion +---------- + +With minimal effort, you can set up a secure logging infrastructure +employing TLS encrypted syslog message transmission. + +Feedback requested +~~~~~~~~~~~~~~~~~~ + +I would appreciate feedback on this tutorial. If you have additional +ideas, comments or find bugs (I \*do\* bugs - no way... ;)), please `let +me know <mailto:rgerhards@adiscon.com>`_. + +Revision History +---------------- + +- 2008-05-06 \* `Rainer Gerhards`_ \* + Initial Version created +- 2008-05-26 \* `Rainer Gerhards`_ \* + added information about certificates diff --git a/source/tutorials/tls_cert.jpg b/source/tutorials/tls_cert.jpg Binary files differnew file mode 100644 index 0000000..920e998 --- /dev/null +++ b/source/tutorials/tls_cert.jpg diff --git a/source/tutorials/tls_cert_100.jpg b/source/tutorials/tls_cert_100.jpg Binary files differnew file mode 100644 index 0000000..beeedc5 --- /dev/null +++ b/source/tutorials/tls_cert_100.jpg diff --git a/source/tutorials/tls_cert_ca.jpg b/source/tutorials/tls_cert_ca.jpg Binary files differnew file mode 100644 index 0000000..f2da045 --- /dev/null +++ b/source/tutorials/tls_cert_ca.jpg diff --git a/source/tutorials/tls_cert_ca.rst b/source/tutorials/tls_cert_ca.rst new file mode 100644 index 0000000..f7127a4 --- /dev/null +++ b/source/tutorials/tls_cert_ca.rst @@ -0,0 +1,147 @@ +Setting up the CA +================= + +The first step is to set up a certificate authority (CA). It must be +maintained by a trustworthy person (or group) and approves the +identities of all machines. It does so by issuing their certificates. +In a small setup, the administrator can provide the CA function. What is +important is the CA's private key is well-protected and machine +certificates are only issued if it is know they are valid (in a +single-admin case that means the admin should not issue certificates to +anyone else except himself). + +The CA creates a so-called self-signed certificate. That is, it approves +its own authenticity. This sounds useless, but the key point to understand +is that every machine will be provided a copy of the CA's certificate. +Accepting this certificate is a matter of trust. So by configuring the +CA certificate, the administrator tells +`rsyslog <http://www.rsyslog.com>`_ which certificates to trust. This is +the root of all trust under this model. That is why the CA's private key +is so important - everyone getting hold of it is trusted by our rsyslog +instances. + +.. figure:: tls_cert_ca.jpg + :align: center + :alt: + +To create a self-signed certificate, use the following commands with +GnuTLS (which is currently the only supported TLS library, what may +change in the future). Please note that GnuTLS' tools are not installed +by default on many platforms. Also, the tools do not necessarily come +with the GnuTLS core package. If you do not have certtool on your +system, check if there is package for the GnuTLS tools available (under +Fedora, for example, this is named gnutls-utils-<version> and it is NOT +installed by default). + +#. generate the private key: + + :: + + certtool --generate-privkey --outfile ca-key.pem + + This takes a short while. Be sure to do some work on your + workstation, it waits for random input. Switching between windows is + sufficient ;) + + +#. now create the (self-signed) CA certificate itself: + + :: + + certtool --generate-self-signed --load-privkey ca-key.pem --outfile ca.pem + + This generates the CA certificate. This command queries you for a + number of things. Use appropriate responses. When it comes to + certificate validity, keep in mind that you need to recreate all + certificates when this one expires. So it may be a good idea to use a + long period, eg. 3650 days (roughly 10 years). You need to specify + that the certificates belongs to an authority. The certificate is + used to sign other certificates. + +Sample Screen Session +~~~~~~~~~~~~~~~~~~~~~ + +Text in red is user input. Please note that for some questions, there is +no user input given. This means the default was accepted by simply +pressing the enter key. + +:: + + [root@rgf9dev sample]# certtool --generate-privkey --outfile ca-key.pem --bits 2048 + Generating a 2048 bit RSA private key... + [root@rgf9dev sample]# certtool --generate-self-signed --load-privkey ca-key.pem --outfile ca.pem + Generating a self signed certificate... + Please enter the details of the certificate's distinguished name. Just press enter to ignore a field. + Country name (2 chars): US + Organization name: SomeOrg + Organizational unit name: SomeOU + Locality name: Somewhere + State or province name: CA + Common name: someName (not necessarily DNS!) + UID: + This field should not be used in new certificates. + E-mail: + Enter the certificate's serial number (decimal): + + + Activation/Expiration time. + The certificate will expire in (days): 3650 + + + Extensions. + Does the certificate belong to an authority? (Y/N): y + Path length constraint (decimal, -1 for no constraint): + Is this a TLS web client certificate? (Y/N): + Is this also a TLS web server certificate? (Y/N): + Enter the e-mail of the subject of the certificate: someone@example.net + Will the certificate be used to sign other certificates? (Y/N): y + Will the certificate be used to sign CRLs? (Y/N): + Will the certificate be used to sign code? (Y/N): + Will the certificate be used to sign OCSP requests? (Y/N): + Will the certificate be used for time stamping? (Y/N): + Enter the URI of the CRL distribution point: + X.509 Certificate Information: + Version: 3 + Serial Number (hex): 485a365e + Validity: + Not Before: Thu Jun 19 10:35:12 UTC 2008 + Not After: Sun Jun 17 10:35:25 UTC 2018 + Subject: C=US,O=SomeOrg,OU=SomeOU,L=Somewhere,ST=CA,CN=someName (not necessarily DNS!) + Subject Public Key Algorithm: RSA + Modulus (bits 2048): + d9:9c:82:46:24:7f:34:8f:60:cf:05:77:71:82:61:66 + 05:13:28:06:7a:70:41:bf:32:85:12:5c:25:a7:1a:5a + 28:11:02:1a:78:c1:da:34:ee:b4:7e:12:9b:81:24:70 + ff:e4:89:88:ca:05:30:0a:3f:d7:58:0b:38:24:a9:b7 + 2e:a2:b6:8a:1d:60:53:2f:ec:e9:38:36:3b:9b:77:93 + 5d:64:76:31:07:30:a5:31:0c:e2:ec:e3:8d:5d:13:01 + 11:3d:0b:5e:3c:4a:32:d8:f3:b3:56:22:32:cb:de:7d + 64:9a:2b:91:d9:f0:0b:82:c1:29:d4:15:2c:41:0b:97 + Exponent: + 01:00:01 + Extensions: + Basic Constraints (critical): + Certificate Authority (CA): TRUE + Subject Alternative Name (not critical): + RFC822name: someone@example.net + Key Usage (critical): + Certificate signing. + Subject Key Identifier (not critical): + fbfe968d10a73ae5b70d7b434886c8f872997b89 + Other Information: + Public Key Id: + fbfe968d10a73ae5b70d7b434886c8f872997b89 + + Is the above information ok? (Y/N): y + + + Signing certificate... + [root@rgf9dev sample]# chmod 400 ca-key.pem + [root@rgf9dev sample]# ls -l + total 8 + -r-------- 1 root root 887 2008-06-19 12:33 ca-key.pem + -rw-r--r-- 1 root root 1029 2008-06-19 12:36 ca.pem + [root@rgf9dev sample]# + +**Be sure to safeguard ca-key.pem!** Nobody except the CA itself needs +to have it. If some third party obtains it, you security is broken! diff --git a/source/tutorials/tls_cert_client.rst b/source/tutorials/tls_cert_client.rst new file mode 100644 index 0000000..6361ef0 --- /dev/null +++ b/source/tutorials/tls_cert_client.rst @@ -0,0 +1,74 @@ +Setting up a client +=================== + +In this step, we configure a client machine. We from our scenario, we +use zuse.example.net. You need to do the same steps for all other +clients, too (in the example, that means turing.example.net). The client +check's the server's identity and talks to it only if it is the expected +server. This is a very important step. Without it, you would not detect +man-in-the-middle attacks or simple malicious servers who try to get +hold of your valuable log data. + +.. figure:: tls_cert_100.jpg + :align: center + :alt: + +Steps to do: + +- make sure you have a functional CA (`Setting up the + CA <tls_cert_ca.html>`_) +- generate a machine certificate for zuse.example.net (follow + instructions in `Generating Machine + Certificates <tls_cert_machine.html>`_) +- make sure you copy over ca.pem, machine-key.pem ad machine-cert.pem + to the client. Ensure that no user except root can access them + (**even read permissions are really bad**). +- configure the client so that it checks the server identity and sends + messages only if the server identity is known. Please note that you + have the same options as when configuring a server. However, we now + use a single name only, because there is only one central server. No + using wildcards make sure that we will exclusively talk to that + server (otherwise, a compromised client may take over its role). If + you load-balance to different server identities, you obviously need to + allow all of them. It still is suggested to use explicit names. + +**At this point, please be reminded once again that your security needs +may be quite different from what we assume in this tutorial. Evaluate +your options based on your security needs.** + +Sample syslog.conf +~~~~~~~~~~~~~~~~~~ + +Keep in mind that this rsyslog.conf sends messages via TCP, only. Also, +we do not show any rules to write local files. Feel free to add them. + +:: + + # make gtls driver the default and set certificate files + global( + DefaultNetstreamDriver="gtls" + DefaultNetstreamDriverCAFile="/path/to/contrib/gnutls/ca.pem" + DefaultNetstreamDriverCertFile="/path/to/contrib/gnutls/cert.pem" + DefaultNetstreamDriverKeyFile="/path/to/contrib/gnutls/key.pem" + ) + + # set up the action for all messages + action( + type="omfwd" + target="central.example.net" + protocol="tcp" + port="6514" + StreamDriver="gtls" + StreamDriverMode="1" # run driver in TLS-only mode + StreamDriverAuthMode="x509/name" + StreamDriverPermittedPeers="central.example.net" + ) + +Note: the example above forwards every message to the remote server. Of +course, you can use the normal filters to restrict the set of +information that is sent. Depending on your message volume and needs, +this may be a smart thing to do. + +**Be sure to safeguard at least the private key (machine-key.pem)!** If +some third party obtains it, you security is broken! + diff --git a/source/tutorials/tls_cert_errmsgs.rst b/source/tutorials/tls_cert_errmsgs.rst new file mode 100644 index 0000000..ff9d9f6 --- /dev/null +++ b/source/tutorials/tls_cert_errmsgs.rst @@ -0,0 +1,111 @@ +Error Messages +============== + +This page covers error message you may see when setting up +`rsyslog <http://www.rsyslog.com>`_ with TLS. Please note that many of +the message stem back to the TLS library being used. In those cases, +there is not always a good explanation available in rsyslog alone. + +A single error typically results in two or more message being emitted: +(at least) one is the actual error cause, followed by usually one +message with additional information (like certificate contents). In a +typical system, these message should immediately follow each other in +your log. Keep in mind that they are reported as syslog.err, so you need +to capture these to actually see errors (the default rsyslog.conf's +shipped by many systems will do that, recording them e.g. in +/etc/messages). + +certificate invalid +------------------- + +Sample: + +:: + + not permitted to talk to peer, certificate invalid: insecure algorithm + +This message may occur during connection setup. It indicates that the +remote peer's certificate can not be accepted. The reason for this is +given in the message part that is shown in red. Please note that this +red part directly stems back to the TLS library, so rsyslog does +actually not have any more information about the reason. + +With GnuTLS, the following reasons have been seen in practice: + +insecure algorithm +^^^^^^^^^^^^^^^^^^ + +The certificate contains information on which encryption algorithms are +to be used. This information is entered when the certificate is created. +Some older algorithms are no longer secure and the TLS library does not +accept them. Thus the connection request failed. The cure is to use a +certificate with sufficiently secure algorithms. + +Please note that no encryption algorithm is totally secure. It only is +secure based on our current knowledge AND on computing power available. +As computers get more and more powerful, previously secure algorithms +become insecure over time. As such, algorithms considered secure today +may not be accepted by the TLS library in the future. + +So in theory, after a system upgrade, a connection request may fail with +the "insecure algorithm" failure without any change in rsyslog +configuration or certificates. This could be caused by a new perception +of the TLS library of what is secure and what not. + +GnuTLS error -64 +---------------- + +Sample: + +:: + + unexpected GnuTLS error -64 in nsd_gtls.c:517: Error while reading file. + +This error points to an encoding error with the pem file in question. +It means "base 64 encoding error". From my experience, it can be caused +by a couple of things, some of them not obvious: + +- You specified a wrong file, which is not actually in .pem format +- The file was incorrectly generated +- I think I have also seen this when I accidentally swapped private key + files and certificate files. So double-check the type of file you are + using. +- It may even be a result of an access (permission) problem. In theory, + that should lead to another error, but in practice it sometimes seems + to lead to this -64 error. + +info on invalid cert +-------------------- + +Sample: + +:: + + info on invalid cert: peer provided 1 certificate(s). Certificate 1 info: certificate valid from Wed Jun 18 11:45:44 2008 to Sat Jun 16 11:45:53 2018; Certificate public key: RSA; DN: C=US,O=Sample Corp,OU=Certs,L=Somewhere,ST=CA,CN=somename; Issuer DN: C=US,O=Sample Corp,OU=Certs,L=Somewhere,ST=CA,CN=somename,EMAIL=xxx@example.com; SAN:DNSname: machine.example.net; + +This is **not** an error message in itself. It always follows the actual +error message and tells you what is seen in the peer's certificate. This +is done to give you a chance to evaluate the certificate and better +understand why the initial error message was issued. + +Please note that you can NOT diagnose problems based on this message +alone. It follows in a number of error cases and does not pinpoint any +problems by itself. + +invalid peer name +----------------- + +Sample: + +:: + + # sender error + error: peer name not authorized - not permitted to talk to it. Names: DNSname: syslog.example.com; CN: syslog.example.com; + + # receiver error + unexpected GnuTLS error -110 in nsd_gtls.c:536: The TLS connection was non-properly terminated. + netstream session 0x7fee240ef650 from X.X.X.X will be closed due to error + +This error is caused by the Subject Alternative Name or Common Name on the receivers certificate not matching any StreamDriverPermittedPeers (RainerScript) / $ActionSendStreamDriverPermittedPeers (Legacy Rsyslog). Either we need to update this parameter with the correct domain name / appropriate wildcard or change the AuthMode of the Stream Driver to be less strict (be sure to carefully read the documentation and understand the implications before taking this route). + +The receiver error is fairly generic and comes from the upstream GnuTLS library, because the sender has decided it's not authorized to talk to the remote peer over TLS it tears down the connection before any records are sent, this is treated as a premature termination by the library and it returns the given error. diff --git a/source/tutorials/tls_cert_machine.rst b/source/tutorials/tls_cert_machine.rst new file mode 100644 index 0000000..e04d171 --- /dev/null +++ b/source/tutorials/tls_cert_machine.rst @@ -0,0 +1,164 @@ +Generating the machine certificate +================================== + +In this step, we generate certificates for each of the machines. Please +note that both clients and servers need certificates. The certificate +identifies each machine to the remote peer. The DNSName specified inside +the certificate can + +be specified inside the $<object>PermittedPeer config statements. + +For now, we assume that a single person (or group) is responsible for +the whole rsyslog system and thus it is OK if that single person is in +possession of all machine's private keys. This simplification permits us +to use a somewhat less complicated way of generating the machine +certificates. So, we generate both the private and public key on the CA +(which is NOT a server!) and then copy them over to the respective +machines. + +If the roles of machine and CA administrators are split, the private key +must be generated by the machine administrator. This is done via a +certificate request. This request is then sent to the CA admin, which in +turn generates the certificate (containing the public key). The CA admin +then sends back the certificate to the machine admin, who installs it. +That way, the CA admin never gets hold of the machine's private key. +Instructions for this mode will be given in a later revision of this +document. + +**In any case, it is vital that the machine's private key is protected. +Anybody able to obtain that private key can impersonate as the machine +to which it belongs, thus breaching your security.** + +Sample Screen Session +~~~~~~~~~~~~~~~~~~~~~ + +Text in red is user input. Please note that for some questions, there is +no user input given. This means the default was accepted by simply +pressing the enter key. + +**Please note:** you need to substitute the names specified below with +values that match your environment. Most importantly, +machine.example.net must be replaced by the actual name of the machine +that will be using this certificate. For example, if you generate a +certificate for a machine named "server.example.com", you need to use +that name. If you generate a certificate for "client.example.com", you +need to use this name. Make sure that each machine certificate has a +unique name. If not, you can not apply proper access control. + +:: + + [root@rgf9dev sample]# certtool --generate-privkey --outfile key.pem --bits 2048 + Generating a 2048 bit RSA private key... + [root@rgf9dev sample]# certtool --generate-request --load-privkey key.pem --outfile request.pem + Generating a PKCS #10 certificate request... + Country name (2 chars): US + Organization name: SomeOrg + Organizational unit name: SomeOU + Locality name: Somewhere + State or province name: CA + Common name: machine.example.net + UID: + Enter a dnsName of the subject of the certificate: + Enter the IP address of the subject of the certificate: + Enter the e-mail of the subject of the certificate: + Enter a challenge password: + Does the certificate belong to an authority? (y/N): n + Will the certificate be used for signing (DHE and RSA-EXPORT ciphersuites)? (y/N): + Will the certificate be used for encryption (RSA ciphersuites)? (y/N): + Is this a TLS web client certificate? (y/N): y + Is this also a TLS web server certificate? (y/N): y + [root@rgf9dev sample]# certtool --generate-certificate --load-request request.pem --outfile cert.pem --load-ca-certificate ca.pem --load-ca-privkey ca-key.pem + Generating a signed certificate... + Enter the certificate's serial number (decimal): + + + Activation/Expiration time. + The certificate will expire in (days): 1000 + + + Extensions. + Do you want to honour the extensions from the request? (y/N): + Does the certificate belong to an authority? (Y/N): n + Will the certificate be used for IPsec IKE operations? (y/N): + Is this a TLS web client certificate? (Y/N): y + Is this also a TLS web server certificate? (Y/N): y + Enter the dnsName of the subject of the certificate: machine.example.net {This is the name of the machine that will use the certificate} + Enter the IP address of the subject of certificate: + Will the certificate be used for signing (DHE and RSA-EXPORT ciphersuites)? (Y/N): + Will the certificate be used for encryption (RSA ciphersuites)? (Y/N): + X.509 Certificate Information: + Version: 3 + Serial Number (hex): 485a3819 + Validity: + Not Before: Thu Jun 19 10:42:54 UTC 2008 + Not After: Wed Mar 16 10:42:57 UTC 2011 + Subject: C=US,O=SomeOrg,OU=SomeOU,L=Somewhere,ST=CA,CN=machine.example.net + Subject Public Key Algorithm: RSA + Modulus (bits 2048): + b2:4e:5b:a9:48:1e:ff:2e:73:a1:33:ee:d8:a2:af:ae + 2f:23:76:91:b8:39:94:00:23:f2:6f:25:ad:c9:6a:ab + 2d:e6:f3:62:d8:3e:6e:8a:d6:1e:3f:72:e5:d8:b9:e0 + d0:79:c2:94:21:65:0b:10:53:66:b0:36:a6:a7:cd:46 + 1e:2c:6a:9b:79:c6:ee:c6:e2:ed:b0:a9:59:e2:49:da + c7:e3:f0:1c:e0:53:98:87:0d:d5:28:db:a4:82:36:ed + 3a:1e:d1:5c:07:13:95:5d:b3:28:05:17:2a:2b:b6:8e + 8e:78:d2:cf:ac:87:13:15:fc:17:43:6b:15:c3:7d:b9 + Exponent: + 01:00:01 + Extensions: + Basic Constraints (critical): + Certificate Authority (CA): FALSE + Key Purpose (not critical): + TLS WWW Client. + TLS WWW Server. + Subject Alternative Name (not critical): + DNSname: machine.example.net + Subject Key Identifier (not critical): + 0ce1c3dbd19d31fa035b07afe2e0ef22d90b28ac + Authority Key Identifier (not critical): + fbfe968d10a73ae5b70d7b434886c8f872997b89 + Other Information: + Public Key Id: + 0ce1c3dbd19d31fa035b07afe2e0ef22d90b28ac + + Is the above information ok? (Y/N): y + + + Signing certificate... + [root@rgf9dev sample]# rm -f request.pem + [root@rgf9dev sample]# ls -l + total 16 + -r-------- 1 root root 887 2008-06-19 12:33 ca-key.pem + -rw-r--r-- 1 root root 1029 2008-06-19 12:36 ca.pem + -rw-r--r-- 1 root root 1074 2008-06-19 12:43 cert.pem + -rw-r--r-- 1 root root 887 2008-06-19 12:40 key.pem + [root@rgf9dev sample]# # it may be a good idea to rename the files to indicate where they belong to + [root@rgf9dev sample]# mv cert.pem machine-cert.pem + [root@rgf9dev sample]# mv key.pem machine-key.pem + [root@rgf9dev sample]# + +Distributing Files +~~~~~~~~~~~~~~~~~~ + +Provide the machine with: + +- a copy of ca.pem +- cert.pem +- key.pem + +This is how the relevant part of rsyslog.conf looks on the target +machine: + +```` + +:: + + global( + DefaultNetstreamDriver="gtls" + DefaultNetstreamDriverCAFile="/path/to/contrib/gnutls/ca.pem" + DefaultNetstreamDriverCertFile="/path/to/contrib/gnutls/cert.pem" + DefaultNetstreamDriverKeyFile="/path/to/contrib/gnutls/key.pem" + ) + +**Never provide anyone with ca-key.pem!** Also, make sure nobody but the +machine in question gets hold of key.pem. diff --git a/source/tutorials/tls_cert_scenario.rst b/source/tutorials/tls_cert_scenario.rst new file mode 100644 index 0000000..86a5442 --- /dev/null +++ b/source/tutorials/tls_cert_scenario.rst @@ -0,0 +1,26 @@ +Sample Use Case: Single Central Log Server +========================================== + +We have a quite simple use case. There is one central syslog server, +named central.example.net. These server is being reported to by two +Linux machines with name zuse.example.net and turing.example.net. Also, +there is a third client - ada.example.net - which send both its own +messages to the central server but also forwards messages receive from +an UDP-only capable router. We have decided to use ada.example.net +because it is in the same local network segment as the router and so we +enjoy TLS' security benefits for forwarding the router messages inside +the corporate network. All systems (except the router) use +`rsyslog <http://www.rsyslog.com/>`_ as the syslog software. + +.. figure:: tls_cert_100.jpg + :align: center + :alt: + +Please note that the CA must not necessarily be connected to the rest of +the network. Actually, it may be considered a security plus if it is +not. If the CA is reachable via the regular network, it should be +sufficiently secured (firewall rules et al). Keep in mind that if the +CA's security is breached, your overall system security is breached. + +In case the CA is compromised, you need to regenerate the CA's +certificate as well as all individual machines certificates. diff --git a/source/tutorials/tls_cert_script.rst b/source/tutorials/tls_cert_script.rst new file mode 100644 index 0000000..e3add83 --- /dev/null +++ b/source/tutorials/tls_cert_script.rst @@ -0,0 +1,159 @@ +Creating certificates with a script +=================================== + +*Written by* `Florian Riedl <https://www.adiscon.com>`_ +*(2019-09-12)* + + +Overview +-------- + +This small article describes is a quick addon to the TLS guides. It describes +in short words, how you can create some quick and dirty certificates for +testing. + +**Disclaimer**: When creating certificates with the attached scripts and more or +less default configurations, you cannot create secure certificates. You need to +use more detailed configuration files to create secure certificates. + + +Description +----------- + +We created a few simple scripts and added configuration files from the sample +configuration in the certtool man page. You can download them here: +:download:`Download Scripts <cert-script.tar.gz>`. + +The tarball contains 6 files, 3 scripts and 3 configurations. To execute, you +must make the scripts executable and have certtool installed via libgnutls. + +- Script 1 creates the CA key and certificate as outlined in `Setting up the CA + <tls_cert_ca.html>`_ + +- Script 2 creates the `machine key and certificate <tls_cert_machine.html>`_ for + a client. + +- Script 3 creates the machine key and certificate for a server. + +These scripts can easily be combined into one. But, we decided to go for +separate scripts so each step can be repeated separately if needed. + +After the scripts are executed, you should have 2 new files per script. +Distribute the files to the machines as described before. + + +Example +------- + +Apart from executing the scripts, no extra input is required. All input from +manual certificate creating can be done automatically via the configuration +template in the cfg files. + +Sample output for the CA certificate generation. +:: + + test@ubuntu:~/Documents$ ./1-generate-ca.sh + ** Note: Please use the --sec-param instead of --bits + Generating a 2048 bit RSA private key... + Generating a self signed certificate... + X.509 Certificate Information: + Version: 3 + Serial Number (hex): 5d7a6351 + Validity: + Not Before: Thu Sep 12 15:25:05 UTC 2019 + Not After: Sun Sep 09 15:25:05 UTC 2029 + Subject: C=US,O=Example,OU=Example,CN=CA-Cert + Subject Public Key Algorithm: RSA + Certificate Security Level: Low + Modulus (bits 2048): + 00:95:28:40:b6:4d:60:7c:cf:72:1d:17:36:b5:f1:11 + 0d:42:05:e9:38:c7:6e:95:d9:42:02:c5:4b:f2:9d:e2 + c8:31:ac:18:ae:55:f7:e0:4c:dd:6d:72:32:01:fa:1d + da:a1:3d:ad:c9:13:0a:68:3e:bc:40:6a:1e:f2:f7:65 + f0:e9:64:fa:84:8b:96:15:b5:10:f3:99:29:14:ee:fc + 88:8d:41:29:8e:c7:9b:23:df:8b:a3:79:28:56:ed:27 + 66:a4:9a:fa:75:47:67:0a:e2:f4:35:98:e8:9e:ad:35 + c2:b2:17:8b:98:72:c4:30:58:fd:13:b6:f4:01:d0:66 + 56:be:61:85:55:dc:91:b6:4e:0a:3f:d4:3f:40:fa:a8 + 92:5e:c5:dd:75:da:c3:27:33:59:43:47:74:fe:d2:28 + 14:49:62:ee:39:22:34:6b:2f:e8:d1:ba:e9:95:6d:29 + d2:6f:8a:a2:fc:c8:da:f0:47:78:3b:2c:03:dc:fb:43 + 31:9e:a1:cb:11:18:b9:0b:31:d3:86:43:68:f8:c4:bd + ab:90:13:33:75:e9:b5:ca:74:c3:83:98:e9:91:3d:39 + fb:65:43:77:0b:b2:bc:3b:33:c2:91:7e:db:c3:a2:a1 + 80:0b:a0:ce:cb:34:29:8b:24:52:25:aa:eb:bd:40:34 + cb + Exponent (bits 24): + 01:00:01 + Extensions: + Basic Constraints (critical): + Certificate Authority (CA): TRUE + Key Usage (critical): + Certificate signing. + Subject Key Identifier (not critical): + 6bbe9a650dbcaf5103c78daf8a2604d76a749f42 + Other Information: + Public Key Id: + 6bbe9a650dbcaf5103c78daf8a2604d76a749f42 + + + + Signing certificate... + +Sample output for the machine certificate generation. +:: + + test@ubuntu:~/Documents$ ./2-generate-client.sh + ** Note: Please use the --sec-param instead of --bits + Generating a 2048 bit RSA private key... + Generating a PKCS #10 certificate request... + Generating a signed certificate... + X.509 Certificate Information: + Version: 3 + Serial Number (hex): 5d7a6402 + Validity: + Not Before: Thu Sep 12 15:28:02 UTC 2019 + Not After: Sun Sep 09 15:28:02 UTC 2029 + Subject: C=US,O=Example,OU=Example,CN=Test Client + Subject Public Key Algorithm: RSA + Certificate Security Level: Low + Modulus (bits 2048): + 00:bd:7f:0b:20:2e:fe:f1:49:91:71:fa:f1:72:76:6b + c0:96:ce:e0:85:80:a3:6a:d2:9e:07:dd:02:94:4f:df + c8:34:13:7d:d1:8f:b8:1b:1f:cf:b8:b7:ae:2f:dd:9a + da:52:6e:a3:f4:73:20:63:32:46:c2:e1:94:73:6b:cd + b4:e4:82:46:25:b0:62:f9:12:28:4f:4f:76:23:5c:47 + 1b:f9:61:cd:68:c1:c1:17:93:90:3c:d2:2b:6e:82:c2 + a3:ca:80:b7:89:6e:b6:16:ae:47:05:e5:b4:07:bf:75 + d9:bd:aa:fe:79:77:72:6e:af:ed:5b:97:d1:e0:00:ba + ab:6f:9e:1f:a6:d4:95:d7:d3:39:88:9b:58:88:28:a0 + 7e:b6:fe:07:7e:68:ad:a1:d0:23:12:3d:96:b2:a8:8e + 73:66:c0:4f:10:a0:e5:9e:ab:2a:37:1d:83:b1:c3:e5 + 7c:35:cc:20:05:7c:7e:41:89:f1:b3:6b:e4:00:f2:bc + 0b:08:55:07:b3:67:e4:14:1c:3c:64:1b:92:2d:d7:f0 + f7:d4:dc:d7:63:1e:fd:e4:98:bc:6b:f1:1a:a9:af:05 + 7a:94:52:f5:b5:36:f0:0c:c0:41:0a:39:b7:fb:b3:50 + c1:ce:ee:24:56:61:77:9d:9e:e1:d0:e1:39:f0:cc:b6 + 29 + Exponent (bits 24): + 01:00:01 + Extensions: + Basic Constraints (critical): + Certificate Authority (CA): FALSE + Key Purpose (not critical): + TLS WWW Client. + TLS WWW Server. + Subject Key Identifier (not critical): + 5a1a7316c4594cafafbeb45ddb49623af3a9f231 + Authority Key Identifier (not critical): + 6bbe9a650dbcaf5103c78daf8a2604d76a749f42 + Other Information: + Public Key Id: + 5a1a7316c4594cafafbeb45ddb49623af3a9f231 + + + + Signing certificate... + +**Be sure to safeguard ca-key.pem!** Nobody except the CA itself needs +to have it. If some third party obtains it, you security is broken! diff --git a/source/tutorials/tls_cert_server.rst b/source/tutorials/tls_cert_server.rst new file mode 100644 index 0000000..8ca57d6 --- /dev/null +++ b/source/tutorials/tls_cert_server.rst @@ -0,0 +1,115 @@ +Setting up the Central Server +============================= + +In this step, we configure the central server. We assume it accepts +messages only via TLS protected plain tcp based syslog from those peers +that are explicitly permitted to send to it. The picture below show our +configuration. This step configures the server central.example.net. + +.. figure:: tls_cert_100.jpg + :align: center + :alt: + +**Important:** *Keep in mind that the order of configuration directives +is very important in rsyslog. As such, the samples given below do only +work if the given order is preserved. Re-ordering the directives can +break configurations and has broken them in practice. If you intend to +re-order them, please be sure that you fully understand how the +configuration language works and, most importantly, which statements +form a block together. Please also note that we understand the +current configuration file format is ugly. However, there has been more +important work in the way of enhancing it. If you would like to +contribute some time to improve the config file language, please let us +know. Any help is appreciated (be it doc or coding work!).* + +Steps to do: + +- make sure you have a functional CA (`Setting up the + CA <tls_cert_ca.html>`_) +- generate a machine certificate for central.example.net (follow + instructions in `Generating Machine + Certificates <tls_cert_machine.html>`_) +- make sure you copy over ca.pem, machine-key.pem ad machine-cert.pem + to the central server. Ensure that no user except root can access + them (**even read permissions are really bad**). +- configure the server so that it accepts messages from all machines in + the example.net domain that have certificates from your CA. + Alternatively, you may also precisely define from which machine names + messages are accepted. See sample rsyslog.conf below. + +In this setup, we use wildcards to ease adding new systems. We permit +the server to accept messages from systems whose names match +\*.example.net. + +:: + + PermittedPeer["*.example.net"] + +This will match zuse.example.net and turing.example.net, but NOT +pascal.otherdepartment.example.net. If the later would be desired, you +can (and need) to include additional permitted peer config statements: + +:: + + PermittedPeer["*.example.net","*.otherdepartment.example.net","*.example.com"] + +As can be seen with example.com, the different permitted peers need NOT +to be in a single domain tree. Also, individual machines can be +configured. For example, if only zuse, turing and ada should be able to +talk to the server, you can achieve this by: + +:: + + PermittedPeer["zuse.example.net","turing.example.net","ada.example.net"] + +As an extension to the (upcoming) IETF syslog/tls standard, you can +specify some text together with a domain component wildcard. So +"\*server.example.net", "server\*.example.net" are valid permitted +peers. However "server\*Fix.example.net" is NOT a valid wildcard. The +IETF standard permits no text along the wildcards. + +The reason we use wildcards in the default setup is that it makes it +easy to add systems without the need to change the central server's +configuration. It is important to understand that the central server +will accept names **only** (no exception) if the client certificate was +signed by the CA we set up. So if someone tries to create a malicious +certificate with a name "zuse.example.net", the server will **not** +accept it. So a wildcard is safe as long as you ensure CA security is +not breached. Actually, you authorize a client by issuing the +certificate to it. + +**At this point, please be reminded once again that your security needs +may be quite different from what we assume in this tutorial. Evaluate +your options based on your security needs.** + +Sample syslog.conf +~~~~~~~~~~~~~~~~~~ + +Keep in mind that this rsyslog.conf accepts messages via TCP, only. The +only other source accepted is messages from the server itself. + +:: + + module(load="imuxsock") # local messages + module(load="imtcp" # TCP listener + StreamDriver.Name="gtls" + StreamDriver.Mode="1" # run driver in TLS-only mode + StreamDriver.Authmode="anon" + ) + + # make gtls driver the default and set certificate files + global( + DefaultNetstreamDriver="gtls" + DefaultNetstreamDriverCAFile="/path/to/contrib/gnutls/ca.pem" + DefaultNetstreamDriverCertFile="/path/to/contrib/gnutls/cert.pem" + DefaultNetstreamDriverKeyFile="/path/to/contrib/gnutls/key.pem" + ) + + # start up listener at port 6514 + input( + type="imtcp" + port="6514" + ) + +**Be sure to safeguard at least the private key (machine-key.pem)!** If +some third party obtains it, you security is broken! diff --git a/source/tutorials/tls_cert_summary.rst b/source/tutorials/tls_cert_summary.rst new file mode 100644 index 0000000..52dae6d --- /dev/null +++ b/source/tutorials/tls_cert_summary.rst @@ -0,0 +1,143 @@ +Encrypting Syslog Traffic with TLS (SSL) +======================================== + +Written by `Rainer Gerhards <https://rainer.gerhards.net>`_ (2008-07-03) + +.. toctree:: + :maxdepth: 1 + + tls_cert_scenario + tls_cert_ca + tls_cert_machine + tls_cert_server + tls_cert_client + tls_cert_udp_relay + tls_cert_errmsgs + tls_cert_script + +Overview +-------- + +This document describes a secure way to set up rsyslog TLS. A secure +logging environment requires more than just encrypting the transmission +channel. This document provides one possible way to create such a secure +system. + +Rsyslog's TLS authentication can be used very flexible and thus supports +a wide range of security policies. This section tries to give some +advise on a scenario that works well for many environments. However, it +may not be suitable for you - please assess you security needs before +using the recommendations below. Do not blame us if it doesn't provide +what you need ;) + +Our policy offers these security benefits: + +- syslog messages are encrypted while traveling on the wire +- the syslog sender authenticates to the syslog receiver; thus, the + receiver knows who is talking to it +- the syslog receiver authenticates to the syslog sender; thus, the + sender can check if it indeed is sending to the expected receiver +- the mutual authentication prevents man-in-the-middle attacks + +Our security goals are achieved via public/private key security. As such, +it is vital that private keys are well protected and not accessible to +third parties. + +If private keys have become known to third parties, the system does not +provide any security at all. Also, our solution bases on X.509 +certificates and a (very limited) chain of trust. We have one instance +(the CA) that issues all machine certificates. The machine certificate +identifies a particular machine. While in theory (and practice), there +could be several "sub-CA" that issues machine certificates for a +specific administrative domain, we do not include this in our "simple yet +secure" setup. If you intend to use this, rsyslog supports it, but then +you need to dig a bit more into the documentation (or use the forum to +ask). In general, if you depart from our simple model, you should have +good reasons for doing so and know quite well what you are doing - +otherwise you may compromise your system security. + +Please note that security never comes without effort. In the scenario +described here, we have limited the effort as much as possible. What +remains is some setup work for the central CA, the certificate setup for +each machine as well as a few configuration commands that need to be +applied to all of them. Probably the most important limiting factor in +our setup is that all senders and receivers must support IETF's +syslog-transport-tls standard (which is not finalized yet). We use +mandatory-to-implement technology, yet you may have trouble finding all +required features in some implementations. More often, unfortunately, +you will find that an implementation does not support the upcoming IETF +standard at all - especially in the "early days" (starting May 2008) +when rsyslog is the only implementation of said standard. + +Fortunately, rsyslog supports almost every protocol that is out there +in the syslog world. So in cases where transport-tls is not available on +a sender, we recommend to use rsyslog as the initial relay. In that +mode, the not-capable sender sends to rsyslog via another protocol, which +then relays the message via transport-tls to either another interim +relay or the final destination (which, of course, must by transport-tls +capable). In such a scenario, it is best to try see what the sender +support. Maybe it is possible to use industry-standard plain tcp syslog +with it. Often you can even combine it with stunnel, which then, too, +enables a secure delivery to the first rsyslog relay. If all of that is +not possible, you can (and often must...) resort to UDP. Even though +this is now lossy and insecure, this is better than not having the +ability to listen to that device at all. It may even be reasonable secure +if the uncapable sender and the first rsyslog relay communicate via a +private channel, e.g. a dedicated network link. + +One final word of caution: transport-tls protects the connection between +the sender and the receiver. It does not necessarily protect against +attacks that are present in the message itself. Especially in a relay +environment, the message may have been originated from a malicious +system, which placed invalid hostnames and/or other content into it. If +there is no provisioning against such things, these records may show up +in the receivers' repository. -transport-tls does not protect against +this (but it may help, properly used). Keep in mind that +syslog-transport-tls provides hop-by-hop security. It does not provide +end-to-end security and it does not authenticate the message itself +(just the last sender). + +If you'd like to get all information very rapidly, the graphic below +contains everything you need to know (from the certificate perspective) +in a very condensed manner. It is no surprise if the graphic puzzles +you. In this case, `simply read on <tls_cert_scenario.html>`_ for full +instructions. + +.. figure:: tls_cert.jpg + :align: center + :alt: TLS/SSL protected syslog + +Summary +~~~~~~~ + +If you followed the steps outlined in this documentation set, you now +have + +a reasonable (for most needs) secure setup for the following +environment: + +.. figure:: tls_cert_100.jpg + :align: center + :alt: + +You have learned about the security decisions involved and which we made +in this example. **Be once again reminded that you must make sure +yourself that whatever you do matches your security needs!** There is no +guarantee that what we generally find useful actually is. It may even be +totally unsuitable for your environment. + +In the example, we created a rsyslog certificate authority (CA). Guard +the CA's files. You need them whenever you need to create a new machine +certificate. We also saw how to generate the machine certificates +themselves and distribute them to the individual machines. Also, you have +found some configuration samples for a server, a client and a syslog +relay. Hopefully, this will enable you to set up a similar system in +many environments. + +Please be warned that you defined some expiration dates for the +certificates. After they are reached, the certificates are no longer +valid and rsyslog will NOT accept them. At that point, syslog messages +will no longer be transmitted (and rsyslogd will heavily begin to +complain). So it is a good idea to make sure that you renew the +certificates before they expire. Recording a reminder somewhere is +probably a good idea. diff --git a/source/tutorials/tls_cert_udp_relay.rst b/source/tutorials/tls_cert_udp_relay.rst new file mode 100644 index 0000000..f0377a8 --- /dev/null +++ b/source/tutorials/tls_cert_udp_relay.rst @@ -0,0 +1,89 @@ +Setting up the UDP syslog relay +=============================== + +In this step, we configure the UDP relay ada.example.net. As a reminder, +that machine relays messages from a local router, which only supports +UDP syslog, to the central syslog server. The router does not talk +directly to it, because we would like to have TLS protection for its +sensitive logs. If the router and the syslog relay are on a sufficiently +secure private network, this setup can be considered reasonable secure. +In any case, it is the best alternative among the possible configuration +scenarios. + +.. figure:: tls_cert_100.jpg + :align: center + :alt: + +Steps to do: + +- make sure you have a functional CA (`Setting up the + CA <tls_cert_ca.html>`_) +- generate a machine certificate for ada.example.net (follow + instructions in `Generating Machine + Certificates <tls_cert_machine.html>`_) +- make sure you copy over ca.pem, machine-key.pem ad machine-cert.pem + to the client. Ensure that no user except root can access them + (**even read permissions are really bad**). +- configure the client so that it checks the server identity and sends + messages only if the server identity is known. + +These were essentially the same steps as for any `TLS syslog +client <tls_cert_client.html>`_. We now need to add the capability to +forward the router logs: + +- make sure that the firewall rules permit message reception on UDP + port 514 (if you use a non-standard port for UDP syslog, make sure + that port number is permitted). +- you may want to limit who can send syslog messages via UDP. A great + place to do this is inside the firewall, but you can also do it in + rsyslog.conf via an $AllowedSender directive. We have used one in the + sample config below. Please be aware that this is a kind of weak + authentication, but definitely better than nothing... +- add the UDP input plugin to rsyslog's config and start a UDP listener +- make sure that your forwarding-filter permits to forward messages + received from the remote router to the server. In our sample + scenario, we do not need to add anything special, because all + messages are forwarded. This includes messages received from remote + hosts. + +**At this point, please be reminded once again that your security needs +may be quite different from what we assume in this tutorial. Evaluate +your options based on your security needs.** + +Sample syslog.conf +~~~~~~~~~~~~~~~~~~ + +Keep in mind that this rsyslog.conf sends messages via TCP, only. Also, +we do not show any rules to write local files. Feel free to add them. + +:: + + # start a UDP listener for the remote router + module(load="imudp") # load UDP server plugin + $AllowedSender UDP, 192.0.2.1 # permit only the router + input(type="imudp" + port="514" # listen on default syslog UDP port 514 + ) + + # make gtls driver the default and set certificate files + global( + DefaultNetstreamDriver="gtls" + DefaultNetstreamDriverCAFile="/path/to/contrib/gnutls/ca.pem" + DefaultNetstreamDriverCertFile="/path/to/contrib/gnutls/cert.pem" + DefaultNetstreamDriverKeyFile="/path/to/contrib/gnutls/key.pem" + ) + + # set up the action for all messages + action( + type="omfwd" + target="central.example.net" + protocol="tcp" + port="6514" + StreamDriver="gtls" + StreamDriverMode="1" # run driver in TLS-only mode + StreamDriverAuthMode="x509/name" + StreamDriverPermittedPeers="central.example.net" + ) + +**Be sure to safeguard at least the private key (machine-key.pem)!** If +some third party obtains it, you security is broken! diff --git a/source/whitepapers/dataflow.png b/source/whitepapers/dataflow.png Binary files differnew file mode 100644 index 0000000..fd614d8 --- /dev/null +++ b/source/whitepapers/dataflow.png diff --git a/source/whitepapers/direct_queue0.png b/source/whitepapers/direct_queue0.png Binary files differnew file mode 100644 index 0000000..6d1b373 --- /dev/null +++ b/source/whitepapers/direct_queue0.png diff --git a/source/whitepapers/direct_queue1.png b/source/whitepapers/direct_queue1.png Binary files differnew file mode 100644 index 0000000..503f815 --- /dev/null +++ b/source/whitepapers/direct_queue1.png diff --git a/source/whitepapers/direct_queue2.png b/source/whitepapers/direct_queue2.png Binary files differnew file mode 100644 index 0000000..cbb99af --- /dev/null +++ b/source/whitepapers/direct_queue2.png diff --git a/source/whitepapers/direct_queue3.png b/source/whitepapers/direct_queue3.png Binary files differnew file mode 100644 index 0000000..cc49299 --- /dev/null +++ b/source/whitepapers/direct_queue3.png diff --git a/source/whitepapers/direct_queue_directq.png b/source/whitepapers/direct_queue_directq.png Binary files differnew file mode 100644 index 0000000..c5d8769 --- /dev/null +++ b/source/whitepapers/direct_queue_directq.png diff --git a/source/whitepapers/direct_queue_rsyslog.png b/source/whitepapers/direct_queue_rsyslog.png Binary files differnew file mode 100644 index 0000000..6150222 --- /dev/null +++ b/source/whitepapers/direct_queue_rsyslog.png diff --git a/source/whitepapers/direct_queue_rsyslog2.png b/source/whitepapers/direct_queue_rsyslog2.png Binary files differnew file mode 100644 index 0000000..807b064 --- /dev/null +++ b/source/whitepapers/direct_queue_rsyslog2.png diff --git a/source/whitepapers/index.rst b/source/whitepapers/index.rst new file mode 100644 index 0000000..c4a46fe --- /dev/null +++ b/source/whitepapers/index.rst @@ -0,0 +1,19 @@ +Rsyslog Whitepapers +=================== + +These are a collection of white papers written by Rainer Gerhards. They detail +logging comparisons and realities based on his experience. They also cover +observations regarding the development of rsyslog and the community around +syslog messaging + +White Papers +------------ + +.. toctree:: + :maxdepth: 1 + + syslog_parsing + syslog_protocol + queues_analogy + preserve_in_nat + reliable_logging.rst diff --git a/source/whitepapers/preserve_in_nat.rst b/source/whitepapers/preserve_in_nat.rst new file mode 100644 index 0000000..61a3a7e --- /dev/null +++ b/source/whitepapers/preserve_in_nat.rst @@ -0,0 +1,18 @@ +Preserving syslog sender over NAT +================================= + +Question: +I have a number of syslog clients behind a NAT device. The receiver receives syslog messages that travelled over the NAT device. This leads the receiver to believe that all messages originated from the same IP address. With stock syslogd, I can not differentiate between the senders. Is there any way to record the correct sender of the message with rsyslog? + +Answer: +OK, I’ve now had some real lab time. The good news in short: if you use rsyslog both on the senders as well as on the receiver, you do NOT have any problems with NAT. + +To double-check (and out of curiosity), I also tried with stock syslogd. I used the ones that came with RedHat and FreeBSD. Neither of them reports the sending machine correctly, they all report the NAT address. Obviously, this is what made this thread appear, but it is a good verification for the correctness of my lab. Next, I tried rsyslogd on the sender and stock syslogd on the receiver (just RedHat this time). The machine was still incorrectly displayed as the NAT address. However, now the real machine name immediately followed the NAT address, so you could differentiate the different machines – but in a inconsistent way. + +Finally, I tried to run the stock syslogds against rsyslogd. Again, the host was not properly displayed. Actually, this time the host was not displayed at all (with the default rsyslogd template). Instead, the tag showed up in the host field. So this configuration is basically unusable. + +The root cause of the NAT issue with stock syslogd obviously is that it does NOT include the HOST header that should be sent as of RFC 3164. This requires the receiver to take the host from the socket, which – in a NATed environment – can only hold the mangled NAT address. Rsyslog instead includes the HOST header, so the actual host name can be taken from that (this is the way rsyslog works with the default templates). + +I barely remember seeing this in code when I initially forked rsyslog from sysklogd. I have not verified it once again. I have also not tested with syslog-ng, simply because that is not my prime focus and a lab would have required too much time. + +To make a long story short: If you use rsyslog on both the senders and receivers, NAT is no issue for you.
\ No newline at end of file diff --git a/source/whitepapers/queue_analogy_tv.png b/source/whitepapers/queue_analogy_tv.png Binary files differnew file mode 100644 index 0000000..fedcb55 --- /dev/null +++ b/source/whitepapers/queue_analogy_tv.png diff --git a/source/whitepapers/queues_analogy.rst b/source/whitepapers/queues_analogy.rst new file mode 100644 index 0000000..7d5fbac --- /dev/null +++ b/source/whitepapers/queues_analogy.rst @@ -0,0 +1,364 @@ +Turning Lanes and Rsyslog Queues +================================ + +If there is a single object absolutely vital to understanding the way +rsyslog works, this object is queues. Queues offer a variety of +services, including support for multithreading. While there is elaborate +in-depth documentation on the ins and outs of :doc:`rsyslog queues +<../concepts/queues>`, some of the concepts are hard to grasp even for +experienced people. I think this is because rsyslog uses a very high +layer of abstraction which includes things that look quite unnatural, +like queues that do **not** actually queue... + +With this document, I take a different approach: I will not describe +every specific detail of queue operation but hope to be able to provide +the core idea of how queues are used in rsyslog by using an analogy. I +will compare the rsyslog data flow with real-life traffic flowing at an +intersection. + +But first let's set the stage for the rsyslog part. The graphic below +describes the data flow inside rsyslog: + +.. figure:: dataflow.png + :align: center + :alt: rsyslog data flow + + rsyslog data flow + +Note that there is a `video +tutorial <http://www.rsyslog.com/Article350.phtml>`_ available on the +data flow. It is not perfect, but may aid in understanding this picture. + +For our needs, the important fact to know is that messages enter rsyslog +on "the left side" (for example, via UDP), are preprocessed, put +into the so-called main queue, taken off that queue, filtered and are +placed into one or several action queues (depending on filter results). +They leave rsyslog on "the right side" where output modules (like the +file or database writer) consume them. + +So there are always **two** stages where a message (conceptually) is +queued - first in the main queue and later on in *n* action specific +queues (with *n* being the number of actions that the message in +question needs to be processed by, what is being decided by the "Filter +Engine"). As such, a message will be in at least two queues during its +lifetime (with the exception of messages being discarded by the queue +itself, but for the purpose of this document, we will ignore that +possibility). + +Also, it is vitally important to understand that **each** action has a +queue sitting in front of it. If you have dug into the details of +rsyslog configuration, you have probably seen that a queue mode can be +set for each action. And the default queue mode is the so-called "direct +mode", in which "the queue does not actually enqueue data". That sounds +silly, but is not. It is an important abstraction that helps keep the +code clean. + +To understand this, we first need to look at who is the active +component. In our data flow, the active part always sits to the left of +the object. For example, the "Preprocessor" is being called by the +inputs and calls itself into the main message queue. That is, the queue +receiver is called, it is passive. One might think that the "Parser & +Filter Engine" is an active component that actively pulls messages from +the queue. This is wrong! Actually, it is the queue that has a pool of +worker threads, and these workers pull data from the queue and then call +the passively waiting Parser and Filter Engine with those messages. So +the main message queue is the active part, the Parser and Filter Engine +is passive. + +Let's now try an analogy analogy for this part: Think about a TV show. +The show is produced in some TV studio, from there sent (actively) to a +radio tower. The radio tower passively receives from the studio and then +actively sends out a signal, which is passively received by your TV set. +In our simplified view, we have the following picture: + +.. figure:: queue_analogy_tv.png + :align: center + :alt: rsyslog queues and TV analogy + + rsyslog queues and TV analogy + +The lower part of the picture lists the equivalent rsyslog entities, in +an abstracted way. Every queue has a producer (in the above sample the +input) and a consumer (in the above sample the Parser and Filter +Engine). Their active and passive functions are equivalent to the TV +entities that are listed on top of the rsyslog entity. For example, a +rsyslog consumer can never actively initiate reception of a message in +the same way a TV set cannot actively "initiate" a TV show - both can +only "handle" (display or process) what is sent to them. + +Now let's look at the action queues: here, the active part, the +producer, is the Parser and Filter Engine. The passive part is the +Action Processor. The latter does any processing that is necessary to +call the output plugin, in particular it processes the template to +create the plugin calling parameters (either a string or vector of +arguments). From the action queue's point of view, Action Processor and +Output form a single entity. Again, the TV set analogy holds. The Output +**does not** actively ask the queue for data, but rather passively waits +until the queue itself pushes some data to it. + +Armed with this knowledge, we can now look at the way action queue modes +work. My analogy here is a junction, as shown below (note that the +colors in the pictures below are **not** related to the colors in the +pictures above!): + +.. figure:: direct_queue0.png + :align: center + :alt: + +This is a very simple real-life traffic case: one road joins another. We +look at traffic on the straight road, here shown by blue and green +arrows. Traffic in the opposing direction is shown in blue. Traffic +flows without any delays as long as nobody takes turns. To be more +precise, if the opposing traffic takes a (right) turn, traffic still +continues to flow without delay. However, if a car in the red traffic +flow intends to do a (left, then) turn, the situation changes: + +.. figure:: direct_queue1.png + :align: center + :alt: + +The turning car is represented by the green arrow. It cannot turn unless +there is a gap in the "blue traffic stream". And as this car blocks the +roadway, the remaining traffic (now shown in red, which should indicate +the block condition), must wait until the "green" car has made its turn. +So a queue will build up on that lane, waiting for the turn to be +completed. Note that in the examples below I do not care that much about +the properties of the opposing traffic. That is, because its structure +is not really important for what I intend to show. Think about the blue +arrow as being a traffic stream that most of the time blocks +left-turners, but from time to time has a gap that is sufficiently large +for a left-turn to complete. + +Our road network designers know that this may be unfortunate, and for +more important roads and junctions, they came up with the concept of +turning lanes: + +.. figure:: direct_queue2.png + :align: center + :alt: + +Now, the car taking the turn can wait in a special area, the turning +lane. As such, the "straight" traffic is no longer blocked and can flow +in parallel to the turning lane (indicated by a now-green-again arrow). + +However, the turning lane offers only finite space. So if too many cars +intend to take a left turn, and there is no gap in the "blue" traffic, +we end up with this well-known situation: + +.. figure:: direct_queue3.png + :align: center + :alt: + +The turning lane is now filled up, resulting in a tailback of cars +intending to left turn on the main driving lane. The end result is that +"straight" traffic is again being blocked, just as in our initial +problem case without the turning lane. In essence, the turning lane has +provided some relief, but only for a limited amount of cars. Street +system designers now try to weight cost vs. benefit and create (costly) +turning lanes that are sufficiently large to prevent traffic jams in +most, but not all cases. + +**Now let's dig a bit into the mathematical properties of turning +lanes.** We assume that cars all have the same length. So, units of +cars, the length is always one (which is nice, as we don't need to care +about that factor any longer ;)). A turning lane has finite capacity of +*n* cars. As long as the number of cars wanting to take a turn is less +than or equal to *n*, "straight traffic" is not blocked (or the other way +round, traffic is blocked if at least *n + 1* cars want to take a +turn!). We can now find an optimal value for *n*: it is a function of +the probability that a car wants to turn and the cost of the turning +lane (as well as the probability there is a gap in the "blue" traffic, +but we ignore this in our simple sample). If we start from some finite +upper bound of *n*, we can decrease *n* to a point where it reaches +zero. But let's first look at *n = 1*, in which case exactly one car can +wait on the turning lane. More than one car, and the rest of the traffic +is blocked. Our everyday logic indicates that this is actually the +lowest boundary for *n*. + +In an abstract view, however, *n* can be zero and that works nicely. +There still can be *n* cars at any given time on the turning lane, it +just happens that this means there can be no car at all on it. And, as +usual, if we have at least *n + 1* cars wanting to turn, the main +traffic flow is blocked. True, but *n + 1 = 0 + 1 = 1* so as soon as +there is any car wanting to take a turn, the main traffic flow is +blocked (remember, in all cases, I assume no sufficiently large gaps in +the opposing traffic). + +This is the situation our everyday perception calls "road without +turning lane". In my math model, it is a "road with turning lane of size +0". The subtle difference is important: my math model guarantees that, +in an abstract sense, there always is a turning lane, it may just be too +short. But it exists, even though we don't see it. And now I can claim +that even in my small home village, all roads have turning lanes, which +is rather impressive, isn't it? ;) + +**And now we finally have arrived at rsyslog's queues!** Rsyslog action +queues exists for all actions just like all roads in my village have +turning lanes! And as in this real-life sample, it may be hard to see +the action queues for that reason. In rsyslog, the "direct" queue mode +is the equivalent to the 0-sized turning lane. And actions queues are +the equivalent to turning lanes in general, with our real-life *n* being +the maximum queue size. The main traffic line (which sometimes is +blocked) is the equivalent to the main message queue. And the periods +without gaps in the opposing traffic are equivalent to execution time of +an action. In a rough sketch, the rsyslog main and action queues look +like in the following picture. + +.. figure:: direct_queue_rsyslog.png + :align: center + :alt: + +We need to read this picture from right to left (otherwise I would need +to redo all the graphics ;)). In action 3, you see a 0-sized turning +lane, aka an action queue in "direct" mode. All other queues are run in +non-direct modes, but with different sizes greater than 0. + +Let us first use our car analogy: Assume we are in a car on the main +lane that wants to take turn into the "action 4" road. We pass action 1, +where a number of cars wait in the turning lane and we pass action 2, +which has a slightly smaller, but still not filled up turning lane. So +we pass that without delay, too. Then we come to "action 3", which has +no turning lane. Unfortunately, the car in front of us wants to turn +left into that road, so it blocks the main lane. So, this time we need +to wait. An observer standing on the sidewalk may see that while we need +to wait, there are still some cars in the "action 4" turning lane. As +such, even though no new cars can arrive on the main lane, cars still +turn into the "action 4" lane. In other words, an observer standing in +"action 4" road is unable to see that traffic on the main lane is +blocked. + +Now on to rsyslog: Other than in the real-world traffic example, +messages in rsyslog can - at more or less the same time - "take turns" +into several roads at once. This is done by duplicating the message if +the road has a non-zero-sized "turning lane" - or in rsyslog terms a +queue that is running in any non-direct mode. If so, a deep copy of the +message object is made, that placed into the action queue and then the +initial message proceeds on the "main lane". The action queue then +pushes the duplicates through action processing. This is also the reason +why a discard action inside a non-direct queue does not seem to have an +effect. Actually, it discards the copy that was just created, but the +original message object continues to flow. + +In action 1, we have some entries in the action queue, as we have in +action 2 (where the queue is slightly shorter). As we have seen, new +messages pass action one and two almost instantaneously. However, when a +messages reaches action 3, its flow is blocked. Now, message processing +must wait for the action to complete. Processing flow in a direct mode +queue is something like a U-turn: + +.. figure:: direct_queue_directq.png + :align: center + :alt: message processing in an rsyslog action queue in direct mode + + message processing in an rsyslog action queue in direct mode + +The message starts to execute the action and once this is done, +processing flow continues. In a real-life analogy, this may be the route +of a delivery man who needs to drop a parcel in a side street before he +continues driving on the main route. As a side-note, think of what +happens with the rest of the delivery route, at least for today, if the +delivery truck has a serious accident in the side street. The rest of +the parcels won't be delivered today, will they? This is exactly how the +discard action works. It drops the message object inside the action and +thus the message will no longer be available for further delivery - but +as I said, only if the discard is done in a direct mode queue (I am +stressing this example because it often causes a lot of confusion). + +Back to the overall scenario. We have seen that messages need to wait +for action 3 to complete. Does this necessarily mean that at the same +time no messages can be processed in action 4? Well, it depends. As in +the real-life scenario, action 4 will continue to receive traffic as +long as its action queue ("turn lane") is not drained. In our drawing, +it is not. So action 4 will be executed while messages still wait for +action 3 to be completed. + +Now look at the overall picture from a slightly different angle: + +.. figure:: direct_queue_rsyslog2.png + :align: center + :alt: message processing in an rsyslog action queue in direct mode + + message processing in an rsyslog action queue in direct mode + +The number of all connected green and red arrows is four - one each for +action 1, 2 and 4 (this one is dotted as action 4 was a special case) +and one for the "main lane" as well as action 3 (this one contains the +sole red arrow). **This number is the lower bound for the number of +threads in rsyslog's output system ("right-hand part" of the main +message queue)!** Each of the connected arrows is a continuous thread +and each "turn lane" is a place where processing is forked onto a new +thread. Also, note that in action 3 the processing is carried out on the +main thread, but not in the non-direct queue modes. + +I have said this is "the lower bound for the number of threads...". This +is with good reason: the main queue may have more than one worker thread +(individual action queues currently do not support this, but could do in +the future - there are good reasons for that, too but exploring why +would finally take us away from what we intend to see). Note that you +configure an upper bound for the number of main message queue worker +threads. The actual number varies depending on a lot of operational +variables, most importantly the number of messages inside the queue. The +number *t\_m* of actually running threads is within the integer-interval +[0,confLimit] (with confLimit being the operator configured limit, which +defaults to 5). Output plugins may have more than one thread created by +themselves. It is quite unusual for an output plugin to create such +threads and so I assume we do not have any of these. Then, the overall +number of threads in rsyslog's filtering and output system is *t\_total += t\_m + number of actions in non-direct modes*. Add the number of +inputs configured to that and you have the total number of threads +running in rsyslog at a given time (assuming again that inputs utilize +only one thread per plugin, a not-so-safe assumption). + +A quick side-note: I gave the lower bound for *t\_m* as zero, which is +somewhat in contrast to what I wrote at the beginning of the last paragraph. +Zero is actually correct, because rsyslog stops all worker threads when +there is no work to do. This is also true for the action queues. So the +ultimate lower bound for a rsyslog output system without any work to +carry out actually is zero. But this bound will never be reached when +there is continuous flow of activity. And, if you are curious: if the +number of workers is zero, the worker wakeup process is actually handled +within the threading context of the "left-hand-side" (or producer) of +the queue. After being started, the worker begins to play the active +queue component again. All of this, of course, can be overridden with +configuration directives. + +When looking at the threading model, one can simply add n lanes to the +main lane but otherwise retain the traffic analogy. This is a very good +description of the actual process (think what this means to the "turning +lanes"; hint: there still is only one per action!). + +**Let's try to do a warp-up:** I have hopefully been able to show that +in rsyslog, an action queue "sits in front of" each output plugin. +Messages are received and flow, from input to output, over various +stages and two level of queues to the outputs. Actions queues are always +present, but may not easily be visible when in direct mode (where no +actual queuing takes place). The "road junction with turning lane" +analogy well describes the way - and intent - of the various queue +levels in rsyslog. + +On the output side, the queue is the active component, **not** the +consumer. As such, the consumer cannot ask the queue for anything (like +n number of messages) but rather is activated by the queue itself. As +such, a queue somewhat resembles a "living thing" whereas the outputs +are just tools that this "living thing" uses. + +**Note that I left out a couple of subtleties**, especially when it +comes to error handling and terminating a queue (you hopefully have now +at least a rough idea why I say "terminating **a queue**" and not +"terminating an action" - *who is the "living thing"?*). An action +returns a status to the queue, but it is the queue that ultimately +decides which messages can finally be considered processed and which +not. Please note that the queue may even cancel an output right in the +middle of its action. This happens, if configured, if an output needs +more than a configured maximum processing time and is a guard condition +to prevent slow outputs from deferring a rsyslog restart for too long. +Especially in this case re-queuing and cleanup is not trivial. Also, +note that I did not discuss disk-assisted queue modes. The basic rules +apply, but there are some additional constraints, especially in regard +to the threading model. Transitioning between actual disk-assisted mode +and pure-in-memory-mode (which is done automatically when needed) is +also far from trivial and a real joy for an implementer to work on ;). + +If you have not done so before, it may be worth reading +:doc:`Understanding rsyslog Queues <../concepts/queues>`, which most +importantly lists all the knobs you can turn to tweak queue operation. diff --git a/source/whitepapers/reliable_logging.rst b/source/whitepapers/reliable_logging.rst new file mode 100644 index 0000000..aef2066 --- /dev/null +++ b/source/whitepapers/reliable_logging.rst @@ -0,0 +1,81 @@ +How reliable should reliable logging be? +======================================== +With any logging, you need to decide what you want to do if the log cannot +be written + +* do you want the application to stop because it can't write a log message + +or + +* do you want the application to continue, but not write the log message + +Note that this decision is still there even if you are not logging +remotely, your local disk partition where you are writing logs can fill up, +become read-only, or have other problems. + +The RFC for syslog (dating back a couple of decades, well before rsyslog +started) specify that the application writing the log message should block +and wait for the log message to be processed. Rsyslog (like every other +modern syslog daemon) fudges this a bit and buffers the log data in RAM +rather than following the original behavior of writing the data to disk and +doing a fsync before acknowledging the log message. + +If you have a problem with your output from rsyslog, your application will +keep running until rsyslog fills it's queues, and then it will stop. + +When you configure rsyslog to send the logs to another machine (either to +rsyslog on another machine or to some sort of database), you introduce a +significant new set of failure modes for the output from rsyslog. + +You can configure the size of the rsyslog memory queues (I had one machine +dedicated to running rsyslog where I created queues large enough to use +>100G of ram for logs) + +You can configure rsyslog to spill from it's memory queues to disk queues +(disk assisted queue mode) when it fills it's memory queues. + +You can create a separate set of queues for the action that has a high +probability of failing (sending to a remote machine via TCP in this case), +but this doesn't buy you more time, it just means that other logs can +continue to be written when the remote system is down. + +You can configure rsyslog to have high/low watermark levels, when the queue +fills past the high watermark, rsyslog will start discarding logs below a +specified severity, and stop doing so when it drops below the low watermark +level + +For rsyslog -> \*syslog, you can use UDP for your transport so that the logs +will get dropped at the network layer if the remote system is unresponsive. + +You have lots of options. + +If you are really concerned with reliability, I should point out that using +TCP does not eliminate the possibility of loosing logs when a remote system +goes down. When you send a message via TCP, the sender considers it sent +when it's handed to the OS to send it. The OS has a window of how much data +it allows to be outstanding (sent without acknowledgement from the remote +system), and when the TCP connection fails (due to a firewall or a remote +machine going down), the sending OS has no way to tell the application what +data what data is outstanding, so the outstanding data will be lost. This +is a smaller window of loss than UDP, which will happily keep sending your +data forever, but it's still a potential for loss. Rsyslog offers the RELP +(Reliable Event Logging Protocol), which addresses this problem by using +application level acknowledgements so no messages can get lost due to +network issues. That just leaves memory buffering (both in rsyslog and in +the OS after rsyslog tells the OS to write the logs) as potential data loss +points. Those failures will only trigger if the system crashes or rsyslog +is shutdown (and yes, there are ways to address these as well) + +The reason why nothing today operates without the possibility of loosing +log messages is that making the logs completely reliable absolutely kills +performance. With buffering, rsyslog can handle 400,000 logs/sec on a +low-mid range machine. With utterly reliable logs and spinning disks, this +rate drops to <100 logs/sec. With a $5K PCI SSD card, you can get up to +~4,000 logs/sec (in both cases, at the cost of not being able to use the +disk for anything else on the system (so if you do use the disk for +anything else, performance drops from there, and pretty rapidly). This is +why traditional syslog had a reputation for being very slow. + +See Also +-------- +* https://rainer.gerhards.net/2008/04/on-unreliability-of-plain-tcp-syslog.html diff --git a/source/whitepapers/syslog_parsing.rst b/source/whitepapers/syslog_parsing.rst new file mode 100644 index 0000000..3e3f2de --- /dev/null +++ b/source/whitepapers/syslog_parsing.rst @@ -0,0 +1,281 @@ +syslog parsing in rsyslog +========================= + +*Written by* `Rainer Gerhards <https://rainer.gerhards.net/>`_, +`Großrinderfeld <https://www.rainer-gerhards.de/grossrinderfeld/>`_ +*(2008-09-23)* + +**We regularly receive messages asking why** +`rsyslog <http://www.rsyslog.com>`_ **parses this or that message +incorrectly.** Of course, it turns out that rsyslog does the right +thing, but the message sender does not. And also of course, this is not +even of the slightest help to the end user experiencing the problem ;). +So I thought I write this paper. It describes the problem source and +shows potential solutions (aha!). + +Syslog Standardization +---------------------- + +The syslog protocol has not been standardized until relatively +recently. The first document "smelling" a bit like a standard is +:rfc:`3164`, which dates back to August +2001. The problem is that this document is no real standard. It has +assigned "informational" status by the `IETF <http://www.ietf.org>`_ +which means it provides some hopefully useful information but does not +demand anything. It is impossible to "comply" to an informational +document. This, of course, doesn't stop marketing guys from telling they +comply to RFC3164 and it also does not stop some techs to tell you "this +and that does not comply to RFC3164, so it is <anybody else but them>'s +fault". + +Then, there is :rfc:`3195`, which +is a real standard. In it's section 3 it makes (a somewhat questionable) +reference to (informational) RFC 3164 which may be interpreted in a way +that RFC3195 standardizes the format layed out in RFC 3164 by virtue of +referencing them. So RFC3195 seems to extend its standardization domain +to the concepts layed out in RFC 3164 (which is why I tend to find that +reference questionable). In that sense, RFC3195 standardizes the format +informationally described in RFC3164, Section 4. But it demands it only +for the scope of RFC3195, which is syslog over BEEP - and NOT syslog +over UDP. So one may argue whether or not the RFC3164 format could be +considered a standard for any non-BEEP (including UDP) syslog, too. In +the strict view I tend to have, it does not. Refering to the RFC3195 +context usually does not help, because there are virtually no RFC3195 +implementations available (at this time, I would consider this RFC a +failure). + +Now let's for a short moment assume that RFC3195 would somehow be able +to demand RFC3164 format for non-BEEP syslog. So we could use RFC3164 +format as a standard. But does that really help? Let's cite RFC 3164, +right at the beginning of section 4 (actually, this is the first +sentence): + + :: + + The payload of any IP packet that has a UDP destination port of 514 + MUST be treated as a syslog message. + + + Think a bit about it: this means that whatever is send to port 514 must be considered + a valid syslog message. No format at all is demanded. So if "this is junk" is sent to + UDP port 514 - voila, we have a valid message (interestingly, it is no longer a syslog + message if it is sent to port 515 ;)). You may now argue that I am overdoing. So let's + cite RFC 3164, Section 5.4, Example 2: + + + Example 2 + + Use the BFG! + + While this is a valid message, it has extraordinarily little useful + information. + +As you can see, RFC3164 explicitly states that no format at all is +required. + +Now a side-note is due: all of this does not mean that the RFC3164 +authors did not know what they were doing. No, right the contrary is +true: RFC3164 mission is to describe what has been seen in practice as +syslog messages and the conclusion is quite right that there is no +common understanding on the message format. This is also the reason why +RFC3164 is an informational document: it provides useful information, +but does not precisely specify anything. + +After all of this bashing, I now have to admit that RFC3164 has some +format recommendations layed out in section 4. The format described has +quite some value in it and implementors recently try to follow it. This +format is usually meant when someone tells you that a software is +"RFC3164 compliant" or expects "RFC3164 compliant messages". I also have +to admit that rsyslog also uses this format and, in the sense outlined +here, expects messages received to be "RFC3164 compliant" (knowingly +that such a beast does not exist - I am simply lying here ;)). + +Please note that there is some relief of the situation in reach. There +is a new normative syslog RFC series upcoming, and it specifies a +standard message format. At the time of this writing, the main documents +are sitting in the RFC editor queue waiting for a transport mapping to +be completed. I personally expect them to be assigned RFC numbers in +2009. + +Update: the numbers are now assigned and the base RFC is :rfc:`5424`. + +Practical Format Requirements +----------------------------- + +From a practical point of view, the message format expected (and +generated by default in legacy mode) is: + +:: + + <PRI>TIMESTAMP SP HOST SP TAG MSG(Freetext) + +SP is the ASCII "space" character and the definition of the rest of the +fields can be taken from RFC3164. Please note that there also is a lot +of confusion on what syntax and semantics the TAG actually has. This +format is called "legacy syslog" because it is not well specified (as +you know by now) and has been "inherited from the real world". + +Rsyslog offers two parsers: one for the upcoming RFC series and one for +legacy format. We concentrate on the later. That parser applies some +logic to detect missing hostnames, is able to handle various ways the +TIMESTAMP is typically malformed. In short it applies a lot of guesswork +in trying to figure out what a message really means. I am sure the +guessing algorithm can be improved, and I am always trying that when I +see new malformed messages (and there is an ample set of them...). +However, this finds its limits where it is not possible to differentiate +between two entities which could be either. For example, look at this +message: + +:: + + <144>Tue Sep 23 11:40:01 taghost sample message + +Does it contain a hostname? Maybe. The value "taghost" is a valid +hostname. Of course, it is also a valid tag. If it is a hostname, the +tag's value is "sample" and the msg value is "message". Or is the +hostname missing, the tag is "taghost" and msg is "sample message"? As a +human, I tend to say the later interpretation is correct. But that's +hard to tell the message parser (and, no, I do not intend to apply +artificial intelligence just to guess what the hostname value is...). + +One approach is to configure the parser so that it never expects +hostnames. This becomes problematic if you receive messages from +multiple devices. Over time, I may implement parser conditionals, but +this is not yet available and I am not really sure if it is needed +complexity... + +Things like this, happen. Even more scary formats happen in practice. +Even from mainstream vendors. For example, I was just asked about this +message (which, btw, finally made me write this article here): + +:: + + "<130> [ERROR] iapp_socket_task.c 399: iappSocketTask: iappRecvPkt returned error" + +If you compare it with the format RFC3164 "suggests", you'll quickly +notice that the message is "a bit" malformed. Actually, even my human +intelligence is not sufficient to guess if there is a TAG or not (is +"[ERROR]" a tag or part of the message). I may not be the smartest guy, +but don't expect me to program a parser that is smarter than me. + +To the best of my knowledge, these vendor's device's syslog format can +be configured, so it would probably be a good idea to include a +(sufficiently well-formed) timestamp, the sending hostname and (maybe?) +a tag to make this message well parseable. I will also once again take +this sample and see if we can apply some guesswork. For example, "[" can +not be part of a well-formed TIMESTAMP, so logic can conclude there is +not TIMESTAMP. Also, "[" can not be used inside a valid hostname, so +logic can conclude that the message contains no hostname. Even if I +implement this logic (which I will probably do), this is a partial +solution: it is impossible to guess if there is a tag or not +(honestly!). And, even worse, it is a solution only for those set of +messages that can be handled by the logic described. Now consider this +hypothetical message: + +:: + + "<130> [ERROR] host.example.net 2008-09-23 11-40-22 PST iapp_socket_task.c 399: iappSocketTask: iappRecvPkt returned error" + +Obviously, it requires additional guesswork. If we iterate over all the +cases, we can very quickly see that it is impossible to guess everything +correct. In the example above we can not even surely tell if PST should +be a timezone or some other message property. + +A potential solution is to generate a parser-table based parser, but +this requires considerable effort and also has quite some runtime +overhead. I try to avoid this for now (but I may do it, especially if +someone sponsors this work ;)). Side-note: if you want to be a bit +scared about potential formats, you may want to have a look at my paper +"`On the Nature of Syslog +Data <http://www.monitorware.com/en/workinprogress/nature-of-syslog-data.php>`_\ ". + +Work-Around +----------- + +**The number one work-around is to configure your devices so that they +emit (sufficiently) well-formed messages.** You should by now know what +these look like. + +If that cure is not available, there are some things you can do in +rsyslog to handle the situation. First of all, be sure to read about +:doc:`rsyslog.conf format <../configuration/basic_structure>` and the +:doc:`property replacer <../configuration/property_replacer>` specifically. You need to +understand that everything is configured in rsyslog. And that the +message is parsed into properties. There are also properties available +which do not stem back directly to parsing. Most importantly, %fromhost% +property holds the name of the system rsyslog received the message from. +In non-relay cases, this can be used instead of hostname. In relay +cases, there is no cure other than to either fix the original sender or +at least one of the relays in front of the rsyslog instance in question. +Similarly, you can use %timegenerated% instead of %timereported%. +Timegenerated is the time the message hit rsyslog for the first time. +For non-relayed, locally connected peers, Timegenerated should be a very +close approximation of the actual time a message was formed at the +sender (depending, of course, on potential internal queueing inside the +sender). Also, you may use the %rawmsg% property together with the +several extraction modes the property replacer supports. Rawmsg contains +the message as it is received from the remote peer. In a sense, you can +implement a post-parser with this method. + +To use these properties, you need to define your own templates and +assign them. Details can be found in the above-quoted documentation. +Just let's do a quick example. Let's say you have the horrible message +shown above and can not fix the sending device for some good reason. In +rsyslog.conf, you used to say: + +:: + + *.* /var/log/somefile + +Of course, things do not work out well with that ill-formed message. So +you decide to dump the rawmsg to the file and pull the remote host and +time of message generation from rsyslog's internal properties (which, +btw, is clever, because otherwise there is no indication of these two +properties...). So you need to define a template for that and make sure +the template is used with your file logging action. This is how it may +look: + +:: + + $template, MalfromedMsgFormater,"%timegenerated% %fromhost% %rawmsg:::drop-last-lf%\n" + *.* /var/log/somefile;MalformedMsgFormatter + +This will make your log much nicer, but not look perfect. Experiment a +bit with the available properties and replacer extraction options to +fine-tune it to your needs. + +The Ultimate Solution... +------------------------ + +Is available with rsyslog 5.3.4 and above. Here, we can define so-called +custom parsers. These are plugin modules, written in C and adapted to a +specific message format need. The big plus of custom parsers is that +they offer excellent performance and unlimited possibilities - far +better than any work-around could do. Custom parsers can be `bound to +specific rule sets <rsconf1_rulesetparser.html>`_ (and thus listening) +ports with relative ease. The only con is that they must be written. +However, if you are lucky, a parser for your device may already exist. +If not, you can opt to write it yourself, what is not too hard if you +know some C. Alternatively, Adiscon can program one for you as part of +the `rsyslog professional services +offering <http://www.rsyslog.com/professional-services>`_. In any case, +you should seriously consider custom parsers as an alternative if you +can not reconfigure your device to send decent message format. + +Wrap-Up +------- + +Syslog message format is not sufficiently standardized. There exists a +weak "standard" format, which is used by a good number of +implementations. However, there exist many others, including mainstream +vendor implementations, which have a (sometimes horribly) different +format. Rsyslog tries to deal with anomalies but can not guess right in +all instances. If possible, the sender should be configured to submit +well-formed messages. If that is not possible, you can work around these +issues with rsyslog's property replacer and template system. Or you can +use a suitable message parser or write one for your needs. + +I hope this is a useful guide. You may also have a look at the `rsyslog +troubleshooting guide <troubleshoot.html>`_ for further help and places +where to ask questions. + diff --git a/source/whitepapers/syslog_protocol.rst b/source/whitepapers/syslog_protocol.rst new file mode 100644 index 0000000..8373f71 --- /dev/null +++ b/source/whitepapers/syslog_protocol.rst @@ -0,0 +1,218 @@ +syslog-protocol support in rsyslog +================================== + +`rsyslog <http://www.rsyslog.com/>`_ **provides a trial implementation +of the proposed** +`syslog-protocol <http://www.monitorware.com/Common/en/glossary/syslog-protocol.php>`_ +**standard.** The intention of this implementation is to find out what +inside syslog-protocol is causing problems during implementation. As +syslog-protocol is a standard under development, its support in rsyslog +is highly volatile. It may change from release to release. So while it +provides some advantages in the real world, users are cautioned against +using it right now. If you do, be prepared that you will probably need +to update all of your rsyslogds with each new release. If you try it +anyhow, please provide feedback as that would be most beneficial for us. + +Currently supported message format +---------------------------------- + +Due to recent discussion on syslog-protocol, we do not follow any +specific revision of the draft but rather the candidate ideas. The +format supported currently is: + +**``<PRI>VERSION SP TIMESTAMP SP HOSTNAME SP APP-NAME SP PROCID SP MSGID SP [SD-ID]s SP MSG``** + +Field syntax and semantics are as defined in IETF I-D +syslog-protocol-15. + +Capabilities Implemented +------------------------ + +- receiving message in the supported format (see above) +- sending messages in the supported format +- relaying messages +- receiving messages in either legacy or -protocol format and + transforming them into the other one +- virtual availability of TAG, PROCID, APP-NAME, MSGID, SD-ID no matter + if the message was received via legacy format, API or syslog-protocol + format (non-present fields are being emulated with great success) +- maximum message size is set via preprocessor #define +- syslog-protocol messages can be transmitted both over UDP and plain + TCP with some restrictions on compliance in the case of TCP + +Findings +-------- + +This lists what has been found during implementation: + +- The same receiver must be able to support both legacy and + syslog-protocol syslog messages. Anything else would be a big + inconvenience to users and would make deployment much harder. The + detection must be done automatically (see below on how easy that is). +- **NUL characters inside MSG** cause the message to be truncated at + that point. This is probably a major point for many C-based + implementations. No measures have yet been taken against this. + Modifying the code to "cleanly" support NUL characters is + non-trivial, even though rsyslogd already has some byte-counted + string library (but this is new and not yet available everywhere). +- **character encoding in MSG**: is is problematic to do the right + UTF-8 encoding. The reason is that we pick up the MSG from the local + domain socket (which got it from the syslog(3) API). The text + obtained does not include any encoding information, but it does + include non US-ASCII characters. It may also include any other + encoding. Other than by guessing based on the provided text, I have + no way to find out what it is. In order to make the syslogd do + anything useful, I have now simply taken the message as is and + stuffed it into the MSG part. Please note that I think this will be a + route that other implementors would take, too. +- A minimal parser is easy to implement. It took me roughly 2 hours to + add it to rsyslogd. This includes the time for restructuring the code + to be able to parse both legacy syslog as well as syslog-protocol. + The parser has some restrictions, though + + - STRUCTURED-DATA field is extracted, but not validated. Structured + data "[test ]]" is not caught as an error. Nor are any other + errors caught. For my needs with this syslogd, that level of + structured data processing is probably sufficient. I do not want + to parse/validate it in all cases. This is also a performance + issue. I think other implementors could have the same view. As + such, we should not make validation a requirement. + - MSG is not further processed (e.g. Unicode not being validated) + - the other header fields are also extracted, but no validation is + performed right now. At least some validation should be easy to + add (not done this because it is a proof-of-concept and scheduled + to change). + +- Universal access to all syslog fields (missing ones being emulated) + was also quite easy. It took me around another 2 hours to integrate + emulation of non-present fields into the code base. +- The version at the start of the message makes it easy to detect if we + have legacy syslog or syslog-protocol. Do NOT move it to somewhere + inside the middle of the message, that would complicate things. It + might not be totally fail-safe to just rely on "1 " as the "cookie" + for a syslog-protocol. Eventually, it would be good to add some more + uniqueness, e.g. "@#1 ". +- I have no (easy) way to detect truncation if that happens on the UDP + stack. All I see is that I receive e.g. a 4K message. If the message + was e.g. 6K, I received two chunks. The first chunk (4K) is correctly + detected as a syslog-protocol message, the second (2K) as legacy + syslog. I do not see what we could do against this. This questions + the usefulness of the TRUNCATE bit. Eventually, I could look at the + UDP headers and see that it is a fragment. I have looked at a network + sniffer log of the conversation. This looks like two + totally-independent messages were sent by the sender stack. +- The maximum message size is currently being configured via a + preprocessor #define. It can easily be set to 2K or 4K, but more than + 4K is not possible because of UDP stack limitations. Eventually, this + can be worked around, but I have not done this yet. +- rsyslogd can accept syslog-protocol formatted messages but is able to + relay them in legacy format. I find this a must in real-life + deployments. For this, I needed to do some field mapping so that + APP-NAME/PROCID are mapped into a TAG. +- rsyslogd can also accept legacy syslog message and relay them in + syslog-protocol format. For this, I needed to apply some sub-parsing + of the TAG, which on most occasions provides correct results. There + might be some misinterpretations but I consider these to be mostly + non-intrusive. +- Messages received from the syslog API (the normal case under \*nix) + also do not have APP-NAME and PROCID and I must parse them out of TAG + as described directly above. As such, this algorithm is absolutely + vital to make things work on \*nix. +- I have an issue with messages received via the syslog(3) API (or, to + be more precise, via the local domain socket this API writes to): + These messages contain a timestamp, but that timestamp does neither + have the year nor the high-resolution time. The year is no real + issue, I just take the year of the reception of that message. There + is a very small window of exposure for messages read from the log + immediately after midnight Jan 1st. The message in the domain socket + might have been written immediately before midnight in the old year. + I think this is acceptable. However, I can not assign a + high-precision timestamp, at least it is somewhat off if I take the + timestamp from message reception on the local socket. An alternative + might be to ignore the timestamp present and instead use that one + when the message is pulled from the local socket (I am talking about + IPC, not the network - just a reminder...). This is doable, but + eventually not advisable. It looks like this needs to be resolved via + a configuration option. +- rsyslogd already advertised its origin information on application + startup (in a syslog-protocol-14 compatible format). It is fairly + easy to include that with any message if desired (not currently + done). +- A big problem I noticed are malformed messages. In -syslog-protocol, + we recommend/require to discard malformed messages. However, in + practice users would like to see everything that the syslogd + receives, even if it is in error. For the first version, I have not + included any error handling at all. However, I think I would + deliberately ignore any "discard" requirement. My current point of + view is that in my code I would eventually flag a message as being + invalid and allow the user to filter on this invalidness. So these + invalid messages could be redirected into special bins. +- The error logging recommendations (those I insisted on;)) are not + really practical. My application has its own error logging philosophy + and I will not change this to follow a draft. +- Relevance of support for leap seconds and senders without knowledge + of time is questionable. I have not made any specific provisions in + the code nor would I know how to handle that differently. I could, + however, pull the local reception timestamp in this case, so it might + be useful to have this feature. I do not think any more about this + for the initial proof-of-concept. Note it as a potential problem + area, especially when logging to databases. +- The HOSTNAME field for internally generated messages currently + contains the hostname part only, not the FQDN. This can be changed + inside the code base, but it requires some thinking so that thinks + are kept compatible with legacy syslog. I have not done this for the + proof-of-concept, but I think it is not really bad. Maybe an hour or + half a day of thinking. +- It is possible that I did not receive a TAG with legacy syslog or via + the syslog API. In this case, I can not generate the APP-NAME. For + consistency, I have used "-" in such cases (just like in PROCID, + MSGID and STRUCTURED-DATA). +- As an architectural side-effect, syslog-protocol formatted messages + can also be transmitted over non-standard syslog/raw tcp. This + implementation uses the industry-standard LF termination of tcp + syslog records. As such, syslog-protocol messages containing a LF + will be broken invalidly. There is nothing that can be done against + this without specifying a TCP transport. This issue might be more + important than one thinks on first thought. The reason is the wide + deployment of syslog/tcp via industry standard. + +**Some notes on syslog-transport-udp-06** + +- I did not make any low-level modifications to the UDP code and think + I am still basically covered with this I-D. +- I deliberately violate section 3.3 insofar as that I do not + necessarily accept messages destined to port 514. This feature is + user-required and a must. The same applies to the destination port. I + am not sure if the "MUST" in section 3.3 was meant that this MUST be + an option, but not necessarily be active. The wording should be + clarified. +- section 3.6: I do not check checksums. See the issue with discarding + messages above. The same solution will probably be applied in my + code. + + + +Conlusions/Suggestions +---------------------- + +These are my personal conclusions and suggestions. Obviously, they must +be discussed ;) + +- NUL should be disallowed in MSG +- As it is not possible to definitely know the character encoding of + the application-provided message, MSG should **not** be specified to + use UTF-8 exclusively. Instead, it is suggested that any encoding may + be used but UTF-8 is preferred. To detect UTF-8, the MSG should start + with the UTF-8 byte order mask of "EF BB BF" if it is UTF-8 encoded + (see section 155.9 of + `http://www.unicode.org/versions/Unicode4.0.0/ch15.pdf <http://www.unicode.org/versions/Unicode4.0.0/ch15.pdf>`_) +- Requirements to drop messages should be reconsidered. I guess I would + not be the only implementor ignoring them. +- Logging requirements should be reconsidered and probably be removed. +- It would be advisable to specify "-" for APP-NAME is the name is not + known to the sender. +- The implications of the current syslog/tcp industry standard on + syslog-protocol should be further evaluated and be fully understood + + + |