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| author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 15:01:30 +0000 |
|---|---|---|
| committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 15:01:30 +0000 |
| commit | 6beeb1b708550be0d4a53b272283e17e5e35fe17 (patch) | |
| tree | 1ce8673d4aaa948e5554000101f46536a1e4cc29 /docs/manual/vhosts/mass.html.en | |
| parent | Initial commit. (diff) | |
| download | apache2-6beeb1b708550be0d4a53b272283e17e5e35fe17.tar.xz apache2-6beeb1b708550be0d4a53b272283e17e5e35fe17.zip | |
Adding upstream version 2.4.57.upstream/2.4.57upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'docs/manual/vhosts/mass.html.en')
| -rw-r--r-- | docs/manual/vhosts/mass.html.en | 348 |
1 files changed, 348 insertions, 0 deletions
diff --git a/docs/manual/vhosts/mass.html.en b/docs/manual/vhosts/mass.html.en new file mode 100644 index 0000000..f5af1e1 --- /dev/null +++ b/docs/manual/vhosts/mass.html.en @@ -0,0 +1,348 @@ +<?xml version="1.0" encoding="UTF-8"?> +<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> +<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en"><head> +<meta content="text/html; charset=UTF-8" http-equiv="Content-Type" /> +<!-- + XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX + This file is generated from xml source: DO NOT EDIT + XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX + --> +<title>Dynamically Configured Mass Virtual Hosting - Apache HTTP Server Version 2.4</title> +<link href="../style/css/manual.css" rel="stylesheet" media="all" type="text/css" title="Main stylesheet" /> +<link href="../style/css/manual-loose-100pc.css" rel="alternate stylesheet" media="all" type="text/css" title="No Sidebar - Default font size" /> +<link href="../style/css/manual-print.css" rel="stylesheet" media="print" type="text/css" /><link rel="stylesheet" type="text/css" href="../style/css/prettify.css" /> +<script src="../style/scripts/prettify.min.js" type="text/javascript"> +</script> + +<link href="../images/favicon.ico" rel="shortcut icon" /></head> +<body id="manual-page"><div id="page-header"> +<p class="menu"><a href="../mod/">Modules</a> | <a href="../mod/directives.html">Directives</a> | <a href="http://wiki.apache.org/httpd/FAQ">FAQ</a> | <a href="../glossary.html">Glossary</a> | <a href="../sitemap.html">Sitemap</a></p> +<p class="apache">Apache HTTP Server Version 2.4</p> +<img alt="" src="../images/feather.png" /></div> +<div class="up"><a href="./"><img title="<-" alt="<-" src="../images/left.gif" /></a></div> +<div id="path"> +<a href="http://www.apache.org/">Apache</a> > <a href="http://httpd.apache.org/">HTTP Server</a> > <a href="http://httpd.apache.org/docs/">Documentation</a> > <a href="../">Version 2.4</a> > <a href="./">Virtual Hosts</a></div><div id="page-content"><div id="preamble"><h1>Dynamically Configured Mass Virtual Hosting</h1> +<div class="toplang"> +<p><span>Available Languages: </span><a href="../en/vhosts/mass.html" title="English"> en </a> | +<a href="../fr/vhosts/mass.html" hreflang="fr" rel="alternate" title="Français"> fr </a> | +<a href="../ko/vhosts/mass.html" hreflang="ko" rel="alternate" title="Korean"> ko </a> | +<a href="../tr/vhosts/mass.html" hreflang="tr" rel="alternate" title="Türkçe"> tr </a></p> +</div> + + + <p>This document describes how to efficiently serve an + arbitrary number of virtual hosts with the Apache HTTP Server. A + <a href="../rewrite/vhosts.html">separate document</a> discusses using + <code class="module"><a href="../mod/mod_rewrite.html">mod_rewrite</a></code> to create dynamic mass virtual hosts. + </p> + +</div> +<div id="quickview"><a href="https://www.apache.org/foundation/contributing.html" class="badge"><img src="https://www.apache.org/images/SupportApache-small.png" alt="Support Apache!" /></a><ul id="toc"><li><img alt="" src="../images/down.gif" /> <a href="#motivation">Motivation</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#overview">Overview</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#simple">Dynamic Virtual Hosts with +mod_vhost_alias</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#homepages">Simplified Dynamic Virtual Hosts</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#combinations">Using Multiple Virtual + Hosting Systems on the Same Server</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#ipbased">More Efficient IP-Based Virtual Hosting</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#rewrite">Mass virtual hosts with +mod_rewrite</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#macro">Mass virtual hosts with mod_macro</a></li> +</ul><h3>See also</h3><ul class="seealso"><li><a href="#comments_section">Comments</a></li></ul></div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="section"> +<h2><a name="motivation" id="motivation">Motivation</a></h2> + + <p>The techniques described here are of interest if your + <code>httpd.conf</code> contains many + <code><VirtualHost></code> sections that are + substantially the same, for example:</p> + +<pre class="prettyprint lang-config"><VirtualHost 111.22.33.44> + ServerName customer-1.example.com + DocumentRoot "/www/hosts/customer-1.example.com/docs" + ScriptAlias "/cgi-bin/" "/www/hosts/customer-1.example.com/cgi-bin" +</VirtualHost> + +<VirtualHost 111.22.33.44> + ServerName customer-2.example.com + DocumentRoot "/www/hosts/customer-2.example.com/docs" + ScriptAlias "/cgi-bin/" "/www/hosts/customer-2.example.com/cgi-bin" +</VirtualHost> + +<VirtualHost 111.22.33.44> + ServerName customer-N.example.com + DocumentRoot "/www/hosts/customer-N.example.com/docs" + ScriptAlias "/cgi-bin/" "/www/hosts/customer-N.example.com/cgi-bin" +</VirtualHost></pre> + + + <p>We wish to replace these multiple + <code><VirtualHost></code> blocks with a mechanism + that works them out dynamically. This has a number of + advantages:</p> + + <ol> + <li>Your configuration file is smaller, so Apache starts + more quickly and uses less memory. Perhaps more importantly, the + smaller configuration is easier to maintain, and leaves less room + for errors.</li> + + <li>Adding virtual hosts is simply a matter of creating the + appropriate directories in the filesystem and entries in the + DNS - you don't need to reconfigure or restart Apache.</li> + </ol> + + <p>The main disadvantage is that you cannot have a different log file for + each virtual host; however, if you have many virtual hosts, doing + this can be a bad idea anyway, because of the <a href="fd-limits.html">number of file descriptors needed</a>. + It is better to <a href="../logs.html#piped">log to a pipe or a fifo</a>, + and arrange for the process at the other end to split up the log + files into one per virtual host. One example of such a process can + be found in the <a href="../programs/split-logfile.html">split-logfile</a> + utility.</p> + +</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="section"> +<h2><a name="overview" id="overview">Overview</a></h2> + + <p>A virtual host is defined by two pieces of information: its + IP address, and the contents of the <code>Host:</code> header + in the HTTP request. The dynamic mass virtual hosting technique + used here is based on automatically inserting this information into the + pathname of the file that is used to satisfy the request. This + can be most easily done by using <code class="module"><a href="../mod/mod_vhost_alias.html">mod_vhost_alias</a></code> + with Apache httpd. Alternatively, + <a href="../rewrite/vhosts.html">mod_rewrite can + be used</a>.</p> + <p>Both of these modules are disabled by default; you must enable + one of them when configuring and building Apache httpd if you want to + use this technique.</p> + + <p>A couple of things need to be determined from the request in + order to make the dynamic + virtual host look like a normal one. The most important is the + server name, which is used by the server to generate + self-referential URLs etc. It is configured with the + <code>ServerName</code> directive, and it is available to CGIs + via the <code>SERVER_NAME</code> environment variable. The + actual value used at run time is controlled by the <code class="directive"><a href="../mod/core.html#usecanonicalname">UseCanonicalName</a></code> + setting. With <code>UseCanonicalName Off</code>, the server name + is taken from the contents of the <code>Host:</code> header in the + request. With <code>UseCanonicalName DNS</code>, it is taken from a + reverse DNS lookup of the virtual host's IP address. The former + setting is used for name-based dynamic virtual hosting, and the + latter is used for IP-based hosting. If httpd cannot work out + the server name because there is no <code>Host:</code> header, + or the DNS lookup fails, then the value configured with + <code>ServerName</code> is used instead.</p> + + <p>The other thing to determine is the document root (configured + with <code>DocumentRoot</code> and available to CGI scripts via the + <code>DOCUMENT_ROOT</code> environment variable). In a normal + configuration, this is used by the core module when + mapping URIs to filenames, but when the server is configured to + do dynamic virtual hosting, that job must be taken over by another + module (either <code class="module"><a href="../mod/mod_vhost_alias.html">mod_vhost_alias</a></code> or + <code class="module"><a href="../mod/mod_rewrite.html">mod_rewrite</a></code>), which has a different way of doing + the mapping. Neither of these modules is responsible for + setting the <code>DOCUMENT_ROOT</code> environment variable so + if any CGIs or SSI documents make use of it, they will get a + misleading value.</p> + +</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="section"> +<h2><a name="simple" id="simple">Dynamic Virtual Hosts with +mod_vhost_alias</a></h2> + + <p>This extract from <code>httpd.conf</code> implements the + virtual host arrangement outlined in the <a href="#motivation">Motivation</a> section above + using <code class="module"><a href="../mod/mod_vhost_alias.html">mod_vhost_alias</a></code>.</p> + +<pre class="prettyprint lang-config"># get the server name from the Host: header +UseCanonicalName Off + +# this log format can be split per-virtual-host based on the first field +# using the split-logfile utility. +LogFormat "%V %h %l %u %t \"%r\" %s %b" vcommon +CustomLog "logs/access_log" vcommon + +# include the server name in the filenames used to satisfy requests +VirtualDocumentRoot "/www/hosts/%0/docs" +VirtualScriptAlias "/www/hosts/%0/cgi-bin"</pre> + + + <p>This configuration can be changed into an IP-based virtual + hosting solution by just turning <code>UseCanonicalName + Off</code> into <code>UseCanonicalName DNS</code>. The server + name that is inserted into the filename is then derived from + the IP address of the virtual host. The variable <code>%0</code> + references the requested servername, as indicated in the + <code>Host:</code> header.</p> + +<p>See the <code class="module"><a href="../mod/mod_vhost_alias.html">mod_vhost_alias</a></code> documentation for more usage +examples.</p> + +</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="section"> +<h2><a name="homepages" id="homepages">Simplified Dynamic Virtual Hosts</a></h2> + + <p>This is an adjustment of the above system, tailored for an + ISP's web hosting server. Using <code>%2</code>, + we can select substrings of the server name to + use in the filename so that, for example, the documents for + <code>www.user.example.com</code> are found in + <code>/home/user/www</code>. It uses a single <code>cgi-bin</code> + directory instead of one per virtual host.</p> + +<pre class="prettyprint lang-config">UseCanonicalName Off + +LogFormat "%V %h %l %u %t \"%r\" %s %b" vcommon +CustomLog "logs/access_log" vcommon + +# include part of the server name in the filenames +VirtualDocumentRoot "/home/%2/www" + +# single cgi-bin directory +ScriptAlias "/cgi-bin/" "/www/std-cgi/"</pre> + + + <p>There are examples of more complicated + <code>VirtualDocumentRoot</code> settings in the + <code class="module"><a href="../mod/mod_vhost_alias.html">mod_vhost_alias</a></code> documentation.</p> + +</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="section"> +<h2><a name="combinations" id="combinations">Using Multiple Virtual + Hosting Systems on the Same Server</a></h2> + + <p>With more complicated setups, you can use httpd's normal + <code><VirtualHost></code> directives to control the + scope of the various virtual hosting configurations. For + example, you could have one IP address for general customers' homepages, + and another for commercial customers, with the following setup. + This can be combined with conventional + <code><VirtualHost></code> configuration sections, as shown + below.</p> + +<pre class="prettyprint lang-config">UseCanonicalName Off + +LogFormat "%V %h %l %u %t \"%r\" %s %b" vcommon + +<Directory "/www/commercial"> + Options FollowSymLinks + AllowOverride All +</Directory> + +<Directory "/www/homepages"> + Options FollowSymLinks + AllowOverride None +</Directory> + +<VirtualHost 111.22.33.44> + ServerName www.commercial.example.com + + CustomLog "logs/access_log.commercial" vcommon + + VirtualDocumentRoot "/www/commercial/%0/docs" + VirtualScriptAlias "/www/commercial/%0/cgi-bin" +</VirtualHost> + +<VirtualHost 111.22.33.45> + ServerName www.homepages.example.com + + CustomLog "logs/access_log.homepages" vcommon + + VirtualDocumentRoot "/www/homepages/%0/docs" + ScriptAlias "/cgi-bin/" "/www/std-cgi/" +</VirtualHost></pre> + + +<div class="note"> + <h3>Note</h3> + <p>If the first VirtualHost block does <em>not</em> include a + <code class="directive"><a href="../mod/core.html#servername">ServerName</a></code> directive, the reverse + DNS of the relevant IP will be used instead. + If this is not the server name you + wish to use, a bogus entry (eg. <code>ServerName + none.example.com</code>) can be added to get around this + behaviour.</p> +</div> + +</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="section"> +<h2><a name="ipbased" id="ipbased">More Efficient IP-Based Virtual Hosting</a></h2> + + <p>The configuration changes suggested to turn <a href="#simple">the first + example</a> into an IP-based virtual hosting setup result in + a rather inefficient setup. A new DNS lookup is required for every + request. To avoid this overhead, the filesystem can be arranged to + correspond to the IP addresses, instead of to the host names, thereby + negating the need for a DNS lookup. Logging will also have to be adjusted + to fit this system.</p> + +<pre class="prettyprint lang-config"># get the server name from the reverse DNS of the IP address +UseCanonicalName DNS + +# include the IP address in the logs so they may be split +LogFormat "%A %h %l %u %t \"%r\" %s %b" vcommon +CustomLog "logs/access_log" vcommon + +# include the IP address in the filenames +VirtualDocumentRootIP "/www/hosts/%0/docs" +VirtualScriptAliasIP "/www/hosts/%0/cgi-bin"</pre> + + +</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="section"> +<h2><a name="rewrite" id="rewrite">Mass virtual hosts with +mod_rewrite</a></h2> + +<p> +Mass virtual hosting may also be accomplished using +<code class="module"><a href="../mod/mod_rewrite.html">mod_rewrite</a></code>, either using simple <code class="directive"><a href="../mod/mod_rewrite.html#rewriterule">RewriteRule</a></code> directives, or using more +complicated techniques such as storing the vhost definitions externally +and accessing them via <code class="directive"><a href="../mod/mod_rewrite.html#rewritemap">RewriteMap</a></code>. These techniques are +discussed in the <a href="../rewrite/vhosts.html">rewrite +documentation</a>.</p> +</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="section"> +<h2><a name="macro" id="macro">Mass virtual hosts with mod_macro</a></h2> + +<p>Another option for dynamically generated virtual hosts is +<code class="module"><a href="../mod/mod_macro.html">mod_macro</a></code>, with which you can create a virtualhost +template, and invoke it for multiple hostnames. An example of this is +provided in the <strong>Usage</strong> section of the module +documentation. +</p> +</div></div> +<div class="bottomlang"> +<p><span>Available Languages: </span><a href="../en/vhosts/mass.html" title="English"> en </a> | +<a href="../fr/vhosts/mass.html" hreflang="fr" rel="alternate" title="Français"> fr </a> | +<a href="../ko/vhosts/mass.html" hreflang="ko" rel="alternate" title="Korean"> ko </a> | +<a href="../tr/vhosts/mass.html" hreflang="tr" rel="alternate" title="Türkçe"> tr </a></p> +</div><div class="top"><a href="#page-header"><img src="../images/up.gif" alt="top" /></a></div><div class="section"><h2><a id="comments_section" name="comments_section">Comments</a></h2><div class="warning"><strong>Notice:</strong><br />This is not a Q&A section. Comments placed here should be pointed towards suggestions on improving the documentation or server, and may be removed by our moderators if they are either implemented or considered invalid/off-topic. Questions on how to manage the Apache HTTP Server should be directed at either our IRC channel, #httpd, on Libera.chat, or sent to our <a href="https://httpd.apache.org/lists.html">mailing lists</a>.</div> +<script type="text/javascript"><!--//--><![CDATA[//><!-- +var comments_shortname = 'httpd'; +var comments_identifier = 'http://httpd.apache.org/docs/2.4/vhosts/mass.html'; +(function(w, d) { + if (w.location.hostname.toLowerCase() == "httpd.apache.org") { + d.write('<div id="comments_thread"><\/div>'); + var s = d.createElement('script'); + s.type = 'text/javascript'; + s.async = true; + s.src = 'https://comments.apache.org/show_comments.lua?site=' + comments_shortname + '&page=' + comments_identifier; + (d.getElementsByTagName('head')[0] || d.getElementsByTagName('body')[0]).appendChild(s); + } + else { + d.write('<div id="comments_thread">Comments are disabled for this page at the moment.<\/div>'); + } +})(window, document); +//--><!]]></script></div><div id="footer"> +<p class="apache">Copyright 2023 The Apache Software Foundation.<br />Licensed under the <a href="http://www.apache.org/licenses/LICENSE-2.0">Apache License, Version 2.0</a>.</p> +<p class="menu"><a href="../mod/">Modules</a> | <a href="../mod/directives.html">Directives</a> | <a href="http://wiki.apache.org/httpd/FAQ">FAQ</a> | <a href="../glossary.html">Glossary</a> | <a href="../sitemap.html">Sitemap</a></p></div><script type="text/javascript"><!--//--><![CDATA[//><!-- +if (typeof(prettyPrint) !== 'undefined') { + prettyPrint(); +} +//--><!]]></script> +</body></html>
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