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diff --git a/man/journalctl.xml b/man/journalctl.xml new file mode 100644 index 0000000..bdead3f --- /dev/null +++ b/man/journalctl.xml @@ -0,0 +1,1112 @@ +<?xml version='1.0'?> <!--*-nxml-*--> +<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" + "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"> +<!-- SPDX-License-Identifier: LGPL-2.1-or-later --> + +<refentry id="journalctl" + xmlns:xi="http://www.w3.org/2001/XInclude"> + + <refentryinfo> + <title>journalctl</title> + <productname>systemd</productname> + </refentryinfo> + + <refmeta> + <refentrytitle>journalctl</refentrytitle> + <manvolnum>1</manvolnum> + </refmeta> + + <refnamediv> + <refname>journalctl</refname> + <refpurpose>Print log entries from the systemd journal</refpurpose> + </refnamediv> + + <refsynopsisdiv> + <cmdsynopsis> + <command>journalctl</command> + <arg choice="opt" rep="repeat">OPTIONS</arg> + <arg choice="opt" rep="repeat">MATCHES</arg> + </cmdsynopsis> + </refsynopsisdiv> + + <refsect1> + <title>Description</title> + + <para><command>journalctl</command> is used to print the log entries stored in the journal by + <citerefentry><refentrytitle>systemd-journald.service</refentrytitle><manvolnum>8</manvolnum></citerefentry> + and + <citerefentry><refentrytitle>systemd-journal-remote.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>. + </para> + + <para>If called without parameters, it will show the contents of the journal accessible to the calling + user, starting with the oldest entry collected.</para> + + <para>If one or more match arguments are passed, the output is filtered accordingly. A match is in the + format <literal>FIELD=VALUE</literal>, e.g. <literal>_SYSTEMD_UNIT=httpd.service</literal>, referring to + the components of a structured journal entry. See + <citerefentry><refentrytitle>systemd.journal-fields</refentrytitle><manvolnum>7</manvolnum></citerefentry> + for a list of well-known fields. If multiple matches are specified matching different fields, the log + entries are filtered by both, i.e. the resulting output will show only entries matching all the specified + matches of this kind. If two matches apply to the same field, then they are automatically matched as + alternatives, i.e. the resulting output will show entries matching any of the specified matches for the + same field. Finally, the character <literal>+</literal> may appear as a separate word between other terms + on the command line. This causes all matches before and after to be combined in a disjunction + (i.e. logical OR).</para> + + <para>It is also possible to filter the entries by specifying an absolute file path as an argument. The + file path may be a file or a symbolic link and the file must exist at the time of the query. If a file + path refers to an executable binary, an <literal>_EXE=</literal> match for the canonicalized binary path + is added to the query. If a file path refers to an executable script, a <literal>_COMM=</literal> match + for the script name is added to the query. If a file path refers to a device node, + <literal>_KERNEL_DEVICE=</literal> matches for the kernel name of the device and for each of its ancestor + devices is added to the query. Symbolic links are dereferenced, kernel names are synthesized, and parent + devices are identified from the environment at the time of the query. In general, a device node is the + best proxy for an actual device, as log entries do not usually contain fields that identify an actual + device. For the resulting log entries to be correct for the actual device, the relevant parts of the + environment at the time the entry was logged, in particular the actual device corresponding to the device + node, must have been the same as those at the time of the query. Because device nodes generally change + their corresponding devices across reboots, specifying a device node path causes the resulting entries to + be restricted to those from the current boot.</para> + + <para>Additional constraints may be added using options <option>--boot</option>, + <option>--unit=</option>, etc., to further limit what entries will be shown (logical AND).</para> + + <para>Output is interleaved from all accessible journal files, whether they are rotated or currently + being written, and regardless of whether they belong to the system itself or are accessible user + journals. The <option>--header</option> option can be used to identify which files + <emphasis>are</emphasis> being shown.</para> + + <para>The set of journal files which will be used can be modified using the <option>--user</option>, + <option>--system</option>, <option>--directory</option>, and <option>--file</option> options, see + below.</para> + + <para>All users are granted access to their private per-user journals. However, by default, only root and + users who are members of a few special groups are granted access to the system journal and the journals + of other users. Members of the groups <literal>systemd-journal</literal>, <literal>adm</literal>, and + <literal>wheel</literal> can read all journal files. Note that the two latter groups traditionally have + additional privileges specified by the distribution. Members of the <literal>wheel</literal> group can + often perform administrative tasks.</para> + + <para>The output is paged through <command>less</command> by default, and long lines are "truncated" to + screen width. The hidden part can be viewed by using the left-arrow and right-arrow keys. Paging can be + disabled; see the <option>--no-pager</option> option and the "Environment" section below.</para> + + <para>When outputting to a tty, lines are colored according to priority: lines of level ERROR and higher + are colored red; lines of level WARNING are colored yellow; lines of level NOTICE are highlighted; + lines of level INFO are displayed normally; lines of level DEBUG are colored grey.</para> + + <para>To write entries <emphasis>to</emphasis> the journal, a few methods may be used. In general, output + from systemd units is automatically connected to the journal, see + <citerefentry><refentrytitle>systemd-journald.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>. + In addition, + <citerefentry><refentrytitle>systemd-cat</refentrytitle><manvolnum>1</manvolnum></citerefentry> + may be used to send messages to the journal directly.</para> + </refsect1> + + <refsect1> + <title>Source Options</title> + + <para>The following options control where to read journal records from:</para> + + <variablelist> + <varlistentry> + <term><option>--system</option></term> + <term><option>--user</option></term> + + <listitem><para>Show messages from system services and the kernel (with + <option>--system</option>). Show messages from service of current user (with + <option>--user</option>). If neither is specified, show all messages that the user can see. + </para> + + <para>The <option>--user</option> option affects how <option>--unit=</option> arguments are + treated. See <option>--unit=</option>.</para> + + <para>Note that <option>--user</option> only works if persistent logging is enabled, via the + <varname>Storage=</varname> setting in + <citerefentry><refentrytitle>journald.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para> + + <xi:include href="version-info.xml" xpointer="v205"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>-M</option></term> + <term><option>--machine=</option></term> + + <listitem><para>Show messages from a running, local container. Specify a container name to connect + to.</para> + + <xi:include href="version-info.xml" xpointer="v209"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>-m</option></term> + <term><option>--merge</option></term> + + <listitem><para>Show entries interleaved from all available journals, including remote + ones.</para> + + <xi:include href="version-info.xml" xpointer="v190"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>-D <replaceable>DIR</replaceable></option></term> + <term><option>--directory=<replaceable>DIR</replaceable></option></term> + + <listitem><para>Takes a directory path as argument. If specified, journalctl will operate on the + specified journal directory <replaceable>DIR</replaceable> instead of the default runtime and system + journal paths.</para> + + <xi:include href="version-info.xml" xpointer="v187"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>--file=<replaceable>GLOB</replaceable></option></term> + + <listitem><para>Takes a file glob as an argument. If specified, journalctl will operate on the + specified journal files matching <replaceable>GLOB</replaceable> instead of the default runtime and + system journal paths. May be specified multiple times, in which case files will be suitably + interleaved.</para> + + <xi:include href="version-info.xml" xpointer="v205"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>--root=<replaceable>ROOT</replaceable></option></term> + + <listitem><para>Takes a directory path as an argument. If specified, <command>journalctl</command> + will operate on journal directories and catalog file hierarchy underneath the specified directory + instead of the root directory (e.g. <option>--update-catalog</option> will create + <filename><replaceable>ROOT</replaceable>/var/lib/systemd/catalog/database</filename>, and journal + files under <filename><replaceable>ROOT</replaceable>/run/journal/</filename> or + <filename><replaceable>ROOT</replaceable>/var/log/journal/</filename> will be displayed). + </para> + + <xi:include href="version-info.xml" xpointer="v201"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>--image=<replaceable>IMAGE</replaceable></option></term> + + <listitem><para>Takes a path to a disk image file or block device node. If specified, + <command>journalctl</command> will operate on the file system in the indicated disk image. This + option is similar to <option>--root=</option>, but operates on file systems stored in disk images or + block devices, thus providing an easy way to extract log data from disk images. The disk image should + either contain just a file system or a set of file systems within a GPT partition table, following + the <ulink url="https://uapi-group.org/specifications/specs/discoverable_partitions_specification">Discoverable Partitions + Specification</ulink>. For further information on supported disk images, see + <citerefentry><refentrytitle>systemd-nspawn</refentrytitle><manvolnum>1</manvolnum></citerefentry>'s + switch of the same name.</para> + + <xi:include href="version-info.xml" xpointer="v247"/></listitem> + </varlistentry> + + <xi:include href="standard-options.xml" xpointer="image-policy-open" /> + + <varlistentry> + <term><option>--namespace=<replaceable>NAMESPACE</replaceable></option></term> + + <listitem><para>Takes a journal namespace identifier string as argument. If not specified the data + collected by the default namespace is shown. If specified shows the log data of the specified + namespace instead. If the namespace is specified as <literal>*</literal> data from all namespaces is + shown, interleaved. If the namespace identifier is prefixed with <literal>+</literal> data from the + specified namespace and the default namespace is shown, interleaved, but no other. For details about + journal namespaces see + <citerefentry><refentrytitle>systemd-journald.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para> + + <xi:include href="version-info.xml" xpointer="v245"/></listitem> + </varlistentry> + </variablelist> + </refsect1> + + <refsect1> + <title>Filtering Options</title> + + <para>The following options control how to filter journal records:</para> + + <variablelist> + <varlistentry> + <term><option>-S</option></term> + <term><option>--since=</option></term> + <term><option>-U</option></term> + <term><option>--until=</option></term> + + <listitem><para>Start showing entries on or newer than the specified date, or on or older than the + specified date, respectively. Date specifications should be of the format <literal>2012-10-30 + 18:17:16</literal>. If the time part is omitted, <literal>00:00:00</literal> is assumed. If only + the seconds component is omitted, <literal>:00</literal> is assumed. If the date component is + omitted, the current day is assumed. Alternatively the strings <literal>yesterday</literal>, + <literal>today</literal>, <literal>tomorrow</literal> are understood, which refer to 00:00:00 of the + day before the current day, the current day, or the day after the current day, + respectively. <literal>now</literal> refers to the current time. Finally, relative times may be + specified, prefixed with <literal>-</literal> or <literal>+</literal>, referring to times before or + after the current time, respectively. For complete time and date specification, see + <citerefentry><refentrytitle>systemd.time</refentrytitle><manvolnum>7</manvolnum></citerefentry>. Note + that <option>--output=short-full</option> prints timestamps that follow precisely this format. + </para> + + <xi:include href="version-info.xml" xpointer="v195"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>-c</option></term> + <term><option>--cursor=</option></term> + + <listitem><para>Start showing entries from the location in the journal specified by the passed + cursor.</para> + + <xi:include href="version-info.xml" xpointer="v193"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>--after-cursor=</option></term> + + <listitem><para>Start showing entries from the location in the journal <emphasis>after</emphasis> + the location specified by the passed cursor. The cursor is shown when the + <option>--show-cursor</option> option is used.</para> + + <xi:include href="version-info.xml" xpointer="v206"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>--cursor-file=<replaceable>FILE</replaceable></option></term> + + <listitem><para>If <replaceable>FILE</replaceable> exists and contains a cursor, start showing + entries <emphasis>after</emphasis> this location. Otherwise show entries according to the other + given options. At the end, write the cursor of the last entry to + <replaceable>FILE</replaceable>. Use this option to continually read the journal by sequentially + calling <command>journalctl</command>.</para> + + <xi:include href="version-info.xml" xpointer="v242"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>-b <optional><optional><replaceable>ID</replaceable></optional><optional><replaceable>±offset</replaceable></optional>|<constant>all</constant></optional></option></term> + <term><option>--boot<optional>=<optional><replaceable>ID</replaceable></optional><optional><replaceable>±offset</replaceable></optional>|<constant>all</constant></optional></option></term> + + <listitem><para>Show messages from a specific boot. This will add a match for + <literal>_BOOT_ID=</literal>.</para> + + <para>The argument may be empty, in which case logs for the current boot will be shown.</para> + + <para>If the boot ID is omitted, a positive <replaceable>offset</replaceable> will look up the boots + starting from the beginning of the journal, and an equal-or-less-than zero + <replaceable>offset</replaceable> will look up boots starting from the end of the journal. Thus, + <constant>1</constant> means the first boot found in the journal in chronological order, + <constant>2</constant> the second and so on; while <constant>-0</constant> is the last boot, + <constant>-1</constant> the boot before last, and so on. An empty <replaceable>offset</replaceable> + is equivalent to specifying <constant>-0</constant>, except when the current boot is not the last + boot (e.g. because <option>--directory</option> was specified to look at logs from a different + machine).</para> + + <para>If the 32-character <replaceable>ID</replaceable> is specified, it may optionally be followed + by <replaceable>offset</replaceable> which identifies the boot relative to the one given by boot + <replaceable>ID</replaceable>. Negative values mean earlier boots and positive values mean later + boots. If <replaceable>offset</replaceable> is not specified, a value of zero is assumed, and the + logs for the boot given by <replaceable>ID</replaceable> are shown.</para> + + <para>The special argument <constant>all</constant> can be used to negate the effect of an earlier + use of <option>-b</option>.</para> + + <xi:include href="version-info.xml" xpointer="v186"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>-u</option></term> + <term><option>--unit=<replaceable>UNIT</replaceable>|<replaceable>PATTERN</replaceable></option></term> + + <listitem><para>Show messages for the specified systemd unit <replaceable>UNIT</replaceable> (such as + a service unit), or for any of the units matched by <replaceable>PATTERN</replaceable>. If a pattern + is specified, a list of unit names found in the journal is compared with the specified pattern and + all that match are used. For each unit name, a match is added for messages from the unit + (<literal>_SYSTEMD_UNIT=<replaceable>UNIT</replaceable></literal>), along with additional matches for + messages from systemd and messages about coredumps for the specified unit. A match is also added for + <literal>_SYSTEMD_SLICE=<replaceable>UNIT</replaceable></literal>, such that if the provided + <replaceable>UNIT</replaceable> is a + <citerefentry><refentrytitle>systemd.slice</refentrytitle><manvolnum>5</manvolnum></citerefentry> + unit, all logs of children of the slice will be shown.</para> + + <para>With <option>--user</option>, all <option>--unit=</option> arguments will be converted to match + user messages as if specified with <option>--user-unit=</option>.</para> + + <para>This parameter can be specified multiple times.</para> + + <xi:include href="version-info.xml" xpointer="v195"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>--user-unit=</option></term> + + <listitem><para>Show messages for the specified user session unit. This will add a match for messages + from the unit (<literal>_SYSTEMD_USER_UNIT=</literal> and <literal>_UID=</literal>) and additional + matches for messages from session systemd and messages about coredumps for the specified unit. A + match is also added for <literal>_SYSTEMD_USER_SLICE=<replaceable>UNIT</replaceable></literal>, such + that if the provided <replaceable>UNIT</replaceable> is a + <citerefentry><refentrytitle>systemd.slice</refentrytitle><manvolnum>5</manvolnum></citerefentry> + unit, all logs of children of the unit will be shown.</para> + + <para>This parameter can be specified multiple times.</para> + + <xi:include href="version-info.xml" xpointer="v198"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>-t</option></term> + <term><option>--identifier=<replaceable>SYSLOG_IDENTIFIER</replaceable></option></term> + + <listitem><para>Show messages for the specified syslog identifier + <replaceable>SYSLOG_IDENTIFIER</replaceable>.</para> + + <para>This parameter can be specified multiple times.</para> + + <xi:include href="version-info.xml" xpointer="v217"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>-p</option></term> + <term><option>--priority=</option></term> + + <listitem><para>Filter output by message priorities or priority ranges. Takes either a single numeric + or textual log level (i.e. between 0/<literal>emerg</literal> and 7/<literal>debug</literal>), or a + range of numeric/text log levels in the form FROM..TO. The log levels are the usual syslog log levels + as documented in <citerefentry + project='man-pages'><refentrytitle>syslog</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + i.e. <literal>emerg</literal> (0), <literal>alert</literal> (1), <literal>crit</literal> (2), + <literal>err</literal> (3), <literal>warning</literal> (4), <literal>notice</literal> (5), + <literal>info</literal> (6), <literal>debug</literal> (7). If a single log level is specified, all + messages with this log level or a lower (hence more important) log level are shown. If a range is + specified, all messages within the range are shown, including both the start and the end value of the + range. This will add <literal>PRIORITY=</literal> matches for the specified + priorities.</para> + + <xi:include href="version-info.xml" xpointer="v188"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>--facility=</option></term> + + <listitem><para>Filter output by syslog facility. Takes a comma-separated list of numbers or + facility names. The names are the usual syslog facilities as documented in <citerefentry + project='man-pages'><refentrytitle>syslog</refentrytitle><manvolnum>3</manvolnum></citerefentry>. + <option>--facility=help</option> may be used to display a list of known facility names and exit. + </para> + + <xi:include href="version-info.xml" xpointer="v245"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>-g</option></term> + <term><option>--grep=</option></term> + + <listitem><para>Filter output to entries where the <varname>MESSAGE=</varname> field matches the + specified regular expression. PERL-compatible regular expressions are used, see <citerefentry + project='url'><refentrytitle + url='http://pcre.org/current/doc/html/pcre2pattern.html'>pcre2pattern</refentrytitle><manvolnum>3</manvolnum></citerefentry> + for a detailed description of the syntax.</para> + + <para>If the pattern is all lowercase, matching is case insensitive. Otherwise, matching is case + sensitive. This can be overridden with the <option>--case-sensitive</option> option, see + below.</para> + + <para>When used with <option>--lines=</option> (not prefixed with <literal>+</literal>), + <option>--reverse</option> is implied.</para> + + <xi:include href="version-info.xml" xpointer="v237"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>--case-sensitive<optional>=BOOLEAN</optional></option></term> + + <listitem><para>Make pattern matching case sensitive or case insensitive.</para> + + <xi:include href="version-info.xml" xpointer="v237"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>-k</option></term> + <term><option>--dmesg</option></term> + + <listitem><para>Show only kernel messages. This implies <option>-b</option> and adds the match + <literal>_TRANSPORT=kernel</literal>.</para> + + <xi:include href="version-info.xml" xpointer="v205"/></listitem> + </varlistentry> + </variablelist> + </refsect1> + + <refsect1> + <title>Output Options</title> + + <para>The following options control how journal records are printed:</para> + + <variablelist> + <varlistentry> + <term><option>-o</option></term> + <term><option>--output=</option></term> + + <listitem><para>Controls the formatting of the journal entries that are shown. Takes one of the + following options:</para> + + <variablelist> + <varlistentry> + <term><option>short</option></term> + <listitem><para>is the default and generates an output that is mostly identical to the + formatting of classic syslog files, showing one line per journal entry.</para> + + <xi:include href="version-info.xml" xpointer="v206"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>short-full</option></term> + <listitem><para>is very similar, but shows timestamps in the format the + <option>--since=</option> and <option>--until=</option> options accept. Unlike the timestamp + information shown in <option>short</option> output mode this mode includes weekday, year and + timezone information in the output, and is locale-independent.</para> + + <xi:include href="version-info.xml" xpointer="v232"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>short-iso</option></term> + <listitem><para>is very similar, but shows timestamps in the + <ulink url="https://tools.ietf.org/html/rfc3339">RFC 3339</ulink> profile of ISO 8601.</para> + + <xi:include href="version-info.xml" xpointer="v206"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>short-iso-precise</option></term> + <listitem><para>as for <option>short-iso</option> but includes full microsecond + precision.</para> + + <xi:include href="version-info.xml" xpointer="v234"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>short-precise</option></term> + <listitem><para>is very similar, but shows classic syslog timestamps with full microsecond + precision.</para> + + <xi:include href="version-info.xml" xpointer="v207"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>short-monotonic</option></term> + <listitem><para>is very similar, but shows monotonic timestamps instead of wallclock + timestamps.</para> + + <xi:include href="version-info.xml" xpointer="v206"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>short-delta</option></term> + <listitem><para>as for <option>short-monotonic</option> but includes the time difference + to the previous entry. + Maybe unreliable time differences are marked by a <literal>*</literal>.</para> + + <xi:include href="version-info.xml" xpointer="v252"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>short-unix</option></term> + <listitem><para>is very similar, but shows seconds passed since January 1st 1970 UTC instead of + wallclock timestamps ("UNIX time"). The time is shown with microsecond accuracy.</para> + + <xi:include href="version-info.xml" xpointer="v230"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>verbose</option></term> + <listitem><para>shows the full-structured entry items with all fields.</para> + + <xi:include href="version-info.xml" xpointer="v206"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>export</option></term> + <listitem><para>serializes the journal into a binary (but mostly text-based) stream suitable + for backups and network transfer (see <ulink + url="https://systemd.io/JOURNAL_EXPORT_FORMATS#journal-export-format">Journal Export + Format</ulink> for more information). To import the binary stream back into native journald + format use + <citerefentry><refentrytitle>systemd-journal-remote</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para> + + <xi:include href="version-info.xml" xpointer="v206"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>json</option></term> + <listitem><para>formats entries as JSON objects, separated by newline characters (see <ulink + url="https://systemd.io/JOURNAL_EXPORT_FORMATS#journal-json-format">Journal JSON Format</ulink> + for more information). Field values are generally encoded as JSON strings, with three exceptions: + <orderedlist> + <listitem><para>Fields larger than 4096 bytes are encoded as <constant>null</constant> + values. (This may be turned off by passing <option>--all</option>, but be aware that this may + allocate overly long JSON objects.)</para></listitem> + + <listitem><para>Journal entries permit non-unique fields within the same log entry. JSON does + not allow non-unique fields within objects. Due to this, if a non-unique field is encountered a + JSON array is used as field value, listing all field values as elements.</para></listitem> + + <listitem><para>Fields containing non-printable or non-UTF8 bytes are encoded as arrays + containing the raw bytes individually formatted as unsigned numbers.</para></listitem> + </orderedlist> + + Note that this encoding is reversible (with the exception of the size limit).</para> + + <xi:include href="version-info.xml" xpointer="v206"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>json-pretty</option></term> + <listitem><para>formats entries as JSON data structures, but formats them in multiple lines in + order to make them more readable by humans.</para> + + <xi:include href="version-info.xml" xpointer="v206"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>json-sse</option></term> + <listitem><para>formats entries as JSON data structures, but wraps them in a format suitable for + <ulink + url="https://developer.mozilla.org/en-US/docs/Server-sent_events/Using_server-sent_events">Server-Sent + Events</ulink>.</para> + + <xi:include href="version-info.xml" xpointer="v206"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>json-seq</option></term> + <listitem><para>formats entries as JSON data structures, but prefixes them with an ASCII Record + Separator character (0x1E) and suffixes them with an ASCII Line Feed character (0x0A), in + accordance with <ulink url="https://tools.ietf.org/html/rfc7464">JavaScript Object Notation + (JSON) Text Sequences </ulink> (<literal>application/json-seq</literal>).</para> + + <xi:include href="version-info.xml" xpointer="v240"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>cat</option></term> + <listitem><para>generates a very terse output, only showing the actual message of each journal + entry with no metadata, not even a timestamp. If combined with the + <option>--output-fields=</option> option will output the listed fields for each log record, + instead of the message.</para> + + <xi:include href="version-info.xml" xpointer="v206"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>with-unit</option></term> + <listitem><para>similar to <option>short-full</option>, but prefixes the unit and user unit names + instead of the traditional syslog identifier. Useful when using templated instances, as it will + include the arguments in the unit names.</para> + + <xi:include href="version-info.xml" xpointer="v239"/></listitem> + </varlistentry> + </variablelist></listitem> + </varlistentry> + + <varlistentry> + <term><option>--truncate-newline</option></term> + + <listitem><para>Truncate each log message at the first newline character on output, so that only the + first line of each message is displayed.</para> + + <xi:include href="version-info.xml" xpointer="v254"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>--output-fields=</option></term> + + <listitem><para>A comma separated list of the fields which should be included in the output. This + has an effect only for the output modes which would normally show all fields + (<option>verbose</option>, <option>export</option>, <option>json</option>, + <option>json-pretty</option>, <option>json-sse</option> and <option>json-seq</option>), as well as + on <option>cat</option>. For the former, the <literal>__CURSOR</literal>, + <literal>__REALTIME_TIMESTAMP</literal>, <literal>__MONOTONIC_TIMESTAMP</literal>, and + <literal>_BOOT_ID</literal> fields are always printed.</para> + + <xi:include href="version-info.xml" xpointer="v236"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>-n</option></term> + <term><option>--lines=</option></term> + + <listitem><para>Show the most recent journal events and limit the number of events shown. The argument + is a positive integer or <literal>all</literal> to disable the limit. Additionally, if the number is + prefixed with <literal>+</literal>, the oldest journal events are used instead. The default value is + 10 if no argument is given.</para> + + <para>If <option>--follow</option> is used, this option is implied. When not prefixed with <literal>+</literal> + and used with <option>--grep=</option>, <option>--reverse</option> is implied.</para></listitem> + </varlistentry> + + <varlistentry> + <term><option>-r</option></term> + <term><option>--reverse</option></term> + + <listitem><para>Reverse output so that the newest entries are displayed first.</para> + + <xi:include href="version-info.xml" xpointer="v198"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>--show-cursor</option></term> + + <listitem><para>The cursor is shown after the last entry after two dashes:</para> + <programlisting>-- cursor: s=0639…</programlisting> + <para>The format of the cursor is private and subject to change.</para> + + <xi:include href="version-info.xml" xpointer="v209"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>--utc</option></term> + + <listitem><para>Express time in Coordinated Universal Time (UTC).</para> + + <xi:include href="version-info.xml" xpointer="v217"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>-x</option></term> + <term><option>--catalog</option></term> + + <listitem><para>Augment log lines with explanation texts from the message catalog. This will add + explanatory help texts to log messages in the output where this is available. These short help texts + will explain the context of an error or log event, possible solutions, as well as pointers to support + forums, developer documentation, and any other relevant manuals. Note that help texts are not + available for all messages, but only for selected ones. For more information on the message catalog, + please refer to the <ulink url="https://www.freedesktop.org/wiki/Software/systemd/catalog">Message + Catalog Developer Documentation</ulink>.</para> + + <para>Note: when attaching <command>journalctl</command> output to bug reports, please do + <emphasis>not</emphasis> use <option>-x</option>.</para> + + <xi:include href="version-info.xml" xpointer="v196"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>--no-hostname</option></term> + + <listitem><para>Don't show the hostname field of log messages originating from the local host. This + switch has an effect only on the <option>short</option> family of output modes (see above).</para> + + <para>Note: this option does not remove occurrences of the hostname from log entries themselves, so + it does not prevent the hostname from being visible in the logs.</para> + + <xi:include href="version-info.xml" xpointer="v230"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>--no-full</option></term> + <term><option>--full</option></term> + <term><option>-l</option></term> + + <listitem><para>Ellipsize fields when they do not fit in available columns. The default is to show + full fields, allowing them to wrap or be truncated by the pager, if one is used.</para> + + <para>The old options <option>-l</option>/<option>--full</option> are not useful anymore, except to + undo <option>--no-full</option>.</para> + + <xi:include href="version-info.xml" xpointer="v196"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>-a</option></term> + <term><option>--all</option></term> + + <listitem><para>Show all fields in full, even if they include unprintable characters or are very + long. By default, fields with unprintable characters are abbreviated as "blob data". (Note that the + pager may escape unprintable characters again.)</para></listitem> + </varlistentry> + + <varlistentry> + <term><option>-f</option></term> + <term><option>--follow</option></term> + + <listitem><para>Show only the most recent journal entries, and continuously print new entries as + they are appended to the journal.</para></listitem> + </varlistentry> + + <varlistentry> + <term><option>--no-tail</option></term> + + <listitem><para>Show all stored output lines, even in follow mode. Undoes the effect of + <option>--lines=</option>.</para></listitem> + </varlistentry> + + <varlistentry> + <term><option>-q</option></term> + <term><option>--quiet</option></term> + + <listitem><para>Suppresses all informational messages (i.e. "-- Journal begins at …", "-- Reboot + --"), any warning messages regarding inaccessible system journals when run as a normal + user.</para></listitem> + </varlistentry> + </variablelist> + </refsect1> + + <refsect1> + <title>Pager Control Options</title> + + <para>The following options control page support:</para> + + <variablelist> + + <xi:include href="standard-options.xml" xpointer="no-pager" /> + + <varlistentry> + <term><option>-e</option></term> + <term><option>--pager-end</option></term> + + <listitem><para>Immediately jump to the end of the journal inside the implied pager tool. This + implies <option>-n1000</option> to guarantee that the pager will not buffer logs of unbounded + size. This may be overridden with an explicit <option>-n</option> with some other numeric value, + while <option>-nall</option> will disable this cap. Note that this option is only supported for + the <citerefentry + project='man-pages'><refentrytitle>less</refentrytitle><manvolnum>1</manvolnum></citerefentry> + pager.</para> + + <xi:include href="version-info.xml" xpointer="v198"/></listitem> + </varlistentry> + </variablelist> + </refsect1> + + <refsect1> + <title>Forward Secure Sealing (FSS) Options</title> + + <para>The following options may be used together with the <option>--setup-keys</option> command described + below:</para> + + <variablelist> + <varlistentry> + <term><option>--interval=</option></term> + + <listitem><para>Specifies the change interval for the sealing key when generating an FSS key pair + with <option>--setup-keys</option>. Shorter intervals increase CPU consumption but shorten the time + range of undetectable journal alterations. Defaults to 15min.</para> + + <xi:include href="version-info.xml" xpointer="v189"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>--verify-key=</option></term> + + <listitem><para>Specifies the FSS verification key to use for the <option>--verify</option> + operation.</para> + + <xi:include href="version-info.xml" xpointer="v189"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>--force</option></term> + + <listitem><para>When <option>--setup-keys</option> is passed and Forward Secure Sealing (FSS) has + already been configured, recreate FSS keys.</para> + + <xi:include href="version-info.xml" xpointer="v206"/></listitem> + </varlistentry> + </variablelist> + </refsect1> + + <refsect1> + <title>Commands</title> + + <para>The following commands are understood. If none is specified the default is to display journal records.</para> + + <variablelist> + <varlistentry> + <term><option>-N</option></term> + <term><option>--fields</option></term> + + <listitem><para>Print all field names currently used in all entries of the journal.</para> + + <xi:include href="version-info.xml" xpointer="v229"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>-F</option></term> + <term><option>--field=</option></term> + + <listitem><para>Print all possible data values the specified field can take in all entries of the + journal.</para> + + <xi:include href="version-info.xml" xpointer="v195"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>--list-boots</option></term> + + <listitem><para>Show a tabular list of boot numbers (relative to the current boot), their IDs, and + the timestamps of the first and last message pertaining to the boot.</para> + + <xi:include href="version-info.xml" xpointer="v209"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>--disk-usage</option></term> + + <listitem><para>Shows the current disk usage of all journal files. This shows the sum of the disk + usage of all archived and active journal files.</para> + + <xi:include href="version-info.xml" xpointer="v190"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>--vacuum-size=</option></term> + <term><option>--vacuum-time=</option></term> + <term><option>--vacuum-files=</option></term> + + <listitem><para><option>--vacuum-size=</option> removes the oldest archived journal files until the + disk space they use falls below the specified size. Accepts the usual <literal>K</literal>, + <literal>M</literal>, <literal>G</literal> and <literal>T</literal> suffixes (to the base of + 1024).</para> + + <para><option>--vacuum-time=</option> removes archived journal files older than the specified + timespan. Accepts the usual <literal>s</literal> (default), <literal>m</literal>, + <literal>h</literal>, <literal>days</literal>, <literal>weeks</literal>, <literal>months</literal>, + and <literal>years</literal> suffixes, see + <citerefentry><refentrytitle>systemd.time</refentrytitle><manvolnum>7</manvolnum></citerefentry> for + details.</para> + + <para><option>--vacuum-files=</option> leaves only the specified number of separate journal + files.</para> + + <para>Note that running <option>--vacuum-size=</option> has only an indirect effect on the output + shown by <option>--disk-usage</option>, as the latter includes active journal files, while the + vacuuming operation only operates on archived journal files. Similarly, + <option>--vacuum-files=</option> might not actually reduce the number of journal files to below the + specified number, as it will not remove active journal files.</para> + + <para><option>--vacuum-size=</option>, <option>--vacuum-time=</option> and + <option>--vacuum-files=</option> may be combined in a single invocation to enforce any combination of + a size, a time and a number of files limit on the archived journal files. Specifying any of these + three parameters as zero is equivalent to not enforcing the specific limit, and is thus + redundant.</para> + + <para>These three switches may also be combined with <option>--rotate</option> into one command. If + so, all active files are rotated first, and the requested vacuuming operation is executed right + after. The rotation has the effect that all currently active files are archived (and potentially new, + empty journal files opened as replacement), and hence the vacuuming operation has the greatest effect + as it can take all log data written so far into account.</para> + + <xi:include href="version-info.xml" xpointer="v218"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>--verify</option></term> + + <listitem><para>Check the journal file for internal consistency. If the file has been generated + with FSS enabled and the FSS verification key has been specified with + <option>--verify-key=</option>, authenticity of the journal file is verified.</para> + + <xi:include href="version-info.xml" xpointer="v189"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>--sync</option></term> + + <listitem><para>Asks the journal daemon to write all yet unwritten journal data to the backing file + system and synchronize all journals. This call does not return until the synchronization operation + is complete. This command guarantees that any log messages written before its invocation are safely + stored on disk at the time it returns.</para> + + <xi:include href="version-info.xml" xpointer="v228"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>--relinquish-var</option></term> + + <listitem><para>Asks the journal daemon for the reverse operation to <option>--flush</option>: if + requested the daemon will write further log data to <filename>/run/log/journal/</filename> and + stops writing to <filename>/var/log/journal/</filename>. A subsequent call to + <option>--flush</option> causes the log output to switch back to + <filename>/var/log/journal/</filename>, see above.</para> + + <xi:include href="version-info.xml" xpointer="v243"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>--smart-relinquish-var</option></term> + + <listitem><para>Similar to <option>--relinquish-var</option>, but executes no operation if the root + file system and <filename>/var/log/journal/</filename> reside on the same mount point. This operation + is used during system shutdown in order to make the journal daemon stop writing data to + <filename>/var/log/journal/</filename> in case that directory is located on a mount point that needs + to be unmounted.</para> + + <xi:include href="version-info.xml" xpointer="v243"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>--flush</option></term> + + <listitem><para>Asks the journal daemon to flush any log data stored in + <filename>/run/log/journal/</filename> into <filename>/var/log/journal/</filename>, if persistent + storage is enabled. This call does not return until the operation is complete. Note that this call is + idempotent: the data is only flushed from <filename>/run/log/journal/</filename> into + <filename>/var/log/journal/</filename> once during system runtime (but see + <option>--relinquish-var</option> below), and this command exits cleanly without executing any + operation if this has already happened. This command effectively guarantees that all data is flushed + to <filename>/var/log/journal/</filename> at the time it returns.</para> + + <xi:include href="version-info.xml" xpointer="v217"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>--rotate</option></term> + + <listitem><para>Asks the journal daemon to rotate journal files. This call does not return until + the rotation operation is complete. Journal file rotation has the effect that all currently active + journal files are marked as archived and renamed, so that they are never written to in future. New + (empty) journal files are then created in their place. This operation may be combined with + <option>--vacuum-size=</option>, <option>--vacuum-time=</option> and + <option>--vacuum-file=</option> into a single command, see above.</para> + + <xi:include href="version-info.xml" xpointer="v227"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>--header</option></term> + + <listitem><para>Instead of showing journal contents, show internal header information of the + journal fields accessed.</para> + + <para>This option is particularly useful when trying to identify out-of-order journal entries, as + happens for example when the machine is booted with the wrong system time.</para> + + <xi:include href="version-info.xml" xpointer="v187"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>--list-catalog <optional><replaceable>128-bit-ID…</replaceable></optional></option></term> + + <listitem><para>List the contents of the message catalog as a table of message IDs, plus their + short description strings.</para> + + <para>If any <replaceable>128-bit-ID</replaceable>s are specified, only those entries are + shown.</para> + + <xi:include href="version-info.xml" xpointer="v196"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>--dump-catalog <optional><replaceable>128-bit-ID…</replaceable></optional></option></term> + + <listitem><para>Show the contents of the message catalog, with entries separated by a line + consisting of two dashes and the ID (the format is the same as <filename>.catalog</filename> + files).</para> + + <para>If any <replaceable>128-bit-ID</replaceable>s are specified, only those entries are + shown.</para> + + <xi:include href="version-info.xml" xpointer="v199"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>--update-catalog</option></term> + + <listitem><para>Update the message catalog index. This command needs to be executed each time new + catalog files are installed, removed, or updated to rebuild the binary catalog + index.</para> + + <xi:include href="version-info.xml" xpointer="v196"/></listitem> + </varlistentry> + + <varlistentry> + <term><option>--setup-keys</option></term> + + <listitem><para>Instead of showing journal contents, generate a new key pair for Forward Secure + Sealing (FSS). This will generate a sealing key and a verification key. The sealing key is stored in + the journal data directory and shall remain on the host. The verification key should be stored + externally. Refer to the <option>Seal=</option> option in + <citerefentry><refentrytitle>journald.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry> for + information on Forward Secure Sealing and for a link to a refereed scholarly paper detailing the + cryptographic theory it is based on.</para> + + <xi:include href="version-info.xml" xpointer="v189"/></listitem> + </varlistentry> + + <xi:include href="standard-options.xml" xpointer="help" /> + <xi:include href="standard-options.xml" xpointer="version" /> + </variablelist> + </refsect1> + + <refsect1> + <title>Exit status</title> + + <para>On success, 0 is returned; otherwise, a non-zero failure code is returned.</para> + </refsect1> + + <xi:include href="common-variables.xml" /> + + <refsect1> + <title>Examples</title> + + <para>Without arguments, all collected logs are shown unfiltered:</para> + + <programlisting>journalctl</programlisting> + + <para>With one match specified, all entries with a field matching the expression are shown:</para> + + <programlisting>journalctl _SYSTEMD_UNIT=avahi-daemon.service +journalctl _SYSTEMD_CGROUP=/user.slice/user-42.slice/session-c1.scope</programlisting> + + <para>If two different fields are matched, only entries matching both expressions at the same time are + shown:</para> + + <programlisting>journalctl _SYSTEMD_UNIT=avahi-daemon.service _PID=28097</programlisting> + + <para>If two matches refer to the same field, all entries matching either expression are shown:</para> + + <programlisting>journalctl _SYSTEMD_UNIT=avahi-daemon.service _SYSTEMD_UNIT=dbus.service</programlisting> + + <para>If the separator <literal>+</literal> is used, two expressions may be combined in a logical OR. The + following will show all messages from the Avahi service process with the PID 28097 plus all messages from + the D-Bus service (from any of its processes):</para> + + <programlisting>journalctl _SYSTEMD_UNIT=avahi-daemon.service _PID=28097 + _SYSTEMD_UNIT=dbus.service</programlisting> + + <para>To show all fields emitted <emphasis>by</emphasis> a unit and <emphasis>about</emphasis> the unit, + option <option>-u</option>/<option>--unit=</option> should be used. <command>journalctl -u + <replaceable>name</replaceable></command> expands to a complex filter similar to + + <programlisting>_SYSTEMD_UNIT=<replaceable>name</replaceable>.service + + UNIT=<replaceable>name</replaceable>.service _PID=1 + + OBJECT_SYSTEMD_UNIT=<replaceable>name</replaceable>.service _UID=0 + + COREDUMP_UNIT=<replaceable>name</replaceable>.service _UID=0 MESSAGE_ID=fc2e22bc6ee647b6b90729ab34a250b1</programlisting> + + (see + <citerefentry><refentrytitle>systemd.journal-fields</refentrytitle><manvolnum>7</manvolnum></citerefentry> + for an explanation of those patterns).</para> + + <para>Show all logs generated by the D-Bus executable:</para> + + <programlisting>journalctl /usr/bin/dbus-daemon</programlisting> + + <para>Show all kernel logs from previous boot:</para> + + <programlisting>journalctl -k -b -1</programlisting> + + <para>Show a live log display from a system service <filename>apache.service</filename>:</para> + + <programlisting>journalctl -f -u apache</programlisting> + </refsect1> + + <refsect1> + <title>See Also</title> + <para> + <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>, + <citerefentry><refentrytitle>systemd-cat</refentrytitle><manvolnum>1</manvolnum></citerefentry>, + <citerefentry><refentrytitle>systemd-journald.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>, + <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>, + <citerefentry><refentrytitle>coredumpctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>, + <citerefentry><refentrytitle>systemd.journal-fields</refentrytitle><manvolnum>7</manvolnum></citerefentry>, + <citerefentry><refentrytitle>journald.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>, + <citerefentry><refentrytitle>systemd.time</refentrytitle><manvolnum>7</manvolnum></citerefentry>, + <citerefentry><refentrytitle>systemd-journal-remote.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>, + <citerefentry><refentrytitle>systemd-journal-upload.service</refentrytitle><manvolnum>8</manvolnum></citerefentry> + </para> + </refsect1> +</refentry> |