fd-limits.html.en revision 4aa603e6448b99f9371397d439795c91a93637ea
55c79512242fd281202cd57ca18defac696440f5kess<?xml version="1.0" encoding="ISO-8859-1"?>
d8a47f7a3f857a43664484552cf83bf170e4629dnd<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
85cbddd6c5822962e3e30a5fa6f45ee4857bc467nd<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en"><head><!--
ec1d455940a366b63e1cce2f442a445347394a90nd XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
55c79512242fd281202cd57ca18defac696440f5kess This file is generated from xml source: DO NOT EDIT
d5d794fc2f4cc9ca6d6da17cfa2cdcd8d244bacdnd XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
031b91a62d25106ae69d4693475c79618dd5e884fielding -->
031b91a62d25106ae69d4693475c79618dd5e884fielding<title>File Descriptor Limits - Apache HTTP Server</title>
031b91a62d25106ae69d4693475c79618dd5e884fielding<link href="/style/css/manual.css" rel="stylesheet" media="all" type="text/css" title="Main stylesheet" />
031b91a62d25106ae69d4693475c79618dd5e884fielding<link href="/style/css/manual-loose-100pc.css" rel="alternate stylesheet" media="all" type="text/css" title="No Sidebar - Default font size" />
031b91a62d25106ae69d4693475c79618dd5e884fielding<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" />
031b91a62d25106ae69d4693475c79618dd5e884fielding<script src="/style/scripts/prettify.min.js" type="text/javascript">
d5d794fc2f4cc9ca6d6da17cfa2cdcd8d244bacdnd</script>
d5d794fc2f4cc9ca6d6da17cfa2cdcd8d244bacdnd
d5d794fc2f4cc9ca6d6da17cfa2cdcd8d244bacdnd<link href="/images/favicon.ico" rel="shortcut icon" /></head>
d5d794fc2f4cc9ca6d6da17cfa2cdcd8d244bacdnd<body id="manual-page" class="no-sidebar"><div id="page-header">
d5d794fc2f4cc9ca6d6da17cfa2cdcd8d244bacdnd<p class="menu"><a href="/mod/">Modules</a> | <a href="/mod/quickreference.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>
d5d794fc2f4cc9ca6d6da17cfa2cdcd8d244bacdnd<p class="apache">Apache HTTP Server Version 2.5</p>
d5d794fc2f4cc9ca6d6da17cfa2cdcd8d244bacdnd<img alt="" src="/images/feather.gif" /></div>
d5d794fc2f4cc9ca6d6da17cfa2cdcd8d244bacdnd<div class="up"><a href="./"><img title="&lt;-" alt="&lt;-" src="/images/left.gif" /></a></div>
d5d794fc2f4cc9ca6d6da17cfa2cdcd8d244bacdnd<div id="path">
d5d794fc2f4cc9ca6d6da17cfa2cdcd8d244bacdnd<a href="http://www.apache.org/">Apache</a> &gt; <a href="http://httpd.apache.org/">HTTP Server</a> &gt; <a href="http://httpd.apache.org/docs/">Documentation</a> &gt; <a href="../">Version 2.5</a> &gt; <a href="./">Virtual Hosts</a></div><div id="page-content"><div id="preamble"><h1>File Descriptor Limits</h1>
7db9f691a00ead175b03335457ca296a33ddf31bnd<div class="toplang">
55c79512242fd281202cd57ca18defac696440f5kess<p><span>Available Languages: </span><a href="/en/vhosts/fd-limits.html" title="English">&nbsp;en&nbsp;</a> |
55c79512242fd281202cd57ca18defac696440f5kess<a href="/fr/vhosts/fd-limits.html" hreflang="fr" rel="alternate" title="Fran�ais">&nbsp;fr&nbsp;</a> |
55c79512242fd281202cd57ca18defac696440f5kess<a href="/ja/vhosts/fd-limits.html" hreflang="ja" rel="alternate" title="Japanese">&nbsp;ja&nbsp;</a> |
ec1d455940a366b63e1cce2f442a445347394a90nd<a href="/ko/vhosts/fd-limits.html" hreflang="ko" rel="alternate" title="Korean">&nbsp;ko&nbsp;</a> |
ec1d455940a366b63e1cce2f442a445347394a90nd<a href="/tr/vhosts/fd-limits.html" hreflang="tr" rel="alternate" title="T�rk�e">&nbsp;tr&nbsp;</a></p>
ec1d455940a366b63e1cce2f442a445347394a90nd</div>
ec1d455940a366b63e1cce2f442a445347394a90nd
ec1d455940a366b63e1cce2f442a445347394a90nd
55c79512242fd281202cd57ca18defac696440f5kess <p>When using a large number of Virtual Hosts, Apache may run
55c79512242fd281202cd57ca18defac696440f5kess out of available file descriptors (sometimes called <cite>file
8f057347a12e831fdf567da83de2fa581580298dnd handles</cite>) if each Virtual Host specifies different log
8f057347a12e831fdf567da83de2fa581580298dnd files. The total number of file descriptors used by Apache is
8f057347a12e831fdf567da83de2fa581580298dnd one for each distinct error log file, one for every other log
8f057347a12e831fdf567da83de2fa581580298dnd file directive, plus 10-20 for internal use. Unix operating
7db9f691a00ead175b03335457ca296a33ddf31bnd systems limit the number of file descriptors that may be used
by a process; the limit is typically 64, and may usually be
increased up to a large hard-limit.</p>
<p>Although Apache attempts to increase the limit as required,
this may not work if:</p>
<ol>
<li>Your system does not provide the <code>setrlimit()</code>
system call.</li>
<li>The <code>setrlimit(RLIMIT_NOFILE)</code> call does not
function on your system (such as Solaris 2.3)</li>
<li>The number of file descriptors required exceeds the hard
limit.</li>
<li>Your system imposes other limits on file descriptors,
such as a limit on stdio streams only using file descriptors
below 256. (Solaris 2)</li>
</ol>
<p>In the event of problems you can:</p>
<ul>
<li>Reduce the number of log files; don't specify log files
in the <code class="directive"><a href="/mod/core.html#virtualhost">&lt;VirtualHost&gt;</a></code>
sections, but only log to the main log files. (See <a href="#splitlogs">Splitting up your log files</a>, below, for more
information on doing this.)</li>
<li>
If you system falls into 1 or 2 (above), then increase the
file descriptor limit before starting Apache, using a
script like
<div class="example"><p><code>
<code>#!/bin/sh<br />
ulimit -S -n 100<br />
exec httpd</code>
</code></p></div>
</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="splitlogs" id="splitlogs">Splitting up your log files</a></h2>
<p>If you want to log multiple virtual hosts to the same log file, you
may want to split up the log files afterwards in order to run
statistical analysis of the various virtual hosts. This can be
accomplished in the following manner.</p>
<p>First, you will need to add the virtual host information to the log
entries. This can be done using the <code class="directive"><a href="/mod/mod_log_config.html#logformat">
LogFormat</a></code>
directive, and the <code>%v</code> variable. Add this to the beginning
of your log format string:</p>
<pre class="prettyprint lang-config">LogFormat "%v %h %l %u %t \"%r\" %&gt;s %b" vhost
CustomLog logs/multiple_vhost_log vhost</pre>
<p>This will create a log file in the common log format, but with the
canonical virtual host (whatever appears in the
<code class="directive"><a href="/mod/core.html#servername">ServerName</a></code> directive) prepended to
each line. (See <code class="module"><a href="/mod/mod_log_config.html">mod_log_config</a></code> for
more about customizing your log files.)</p>
<p>When you wish to split your log file into its component parts (one
file per virtual host) you can use the program <code><a href="/programs/other.html">split-logfile</a></code> to accomplish
this. You'll find this program in the <code>support</code> directory
of the Apache distribution.</p>
<p>Run this program with the command:</p>
<div class="example"><p><code>
split-logfile &lt; /logs/multiple_vhost_log
</code></p></div>
<p>This program, when run with the name of your vhost log file, will
generate one file for each virtual host that appears in your log file.
Each file will be called <code>hostname.log</code>.</p>
</div></div>
<div class="bottomlang">
<p><span>Available Languages: </span><a href="/en/vhosts/fd-limits.html" title="English">&nbsp;en&nbsp;</a> |
<a href="/fr/vhosts/fd-limits.html" hreflang="fr" rel="alternate" title="Fran�ais">&nbsp;fr&nbsp;</a> |
<a href="/ja/vhosts/fd-limits.html" hreflang="ja" rel="alternate" title="Japanese">&nbsp;ja&nbsp;</a> |
<a href="/ko/vhosts/fd-limits.html" hreflang="ko" rel="alternate" title="Korean">&nbsp;ko&nbsp;</a> |
<a href="/tr/vhosts/fd-limits.html" hreflang="tr" rel="alternate" title="T�rk�e">&nbsp;tr&nbsp;</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&amp;A section. Comments placed here should be pointed towards suggestions on improving the documentation or server, and may be removed again 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 Freenode, or sent to our <a href="http://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/trunk/vhosts/fd-limits.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 2014 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/quickreference.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>