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<modulesynopsis metafile="mod_status.xml.meta">

<name>mod_status</name>

<description>Provides information on server activity and

performance</description>

<status>Base</status>

<sourcefile>mod_status.c</sourcefile>

<identifier>status_module</identifier>

<summary>

<p>The Status module allows a server administrator to find out

how well their server is performing. A HTML page is presented

that gives the current server statistics in an easily readable

form. If required this page can be made to automatically

refresh (given a compatible browser). Another page gives a

simple machine-readable list of the current server state.</p>

<p>The details given are:</p>

<ul>

<li>The number of worker serving requests</li>

<li>The number of idle worker</li>

<li>The status of each worker, the number of requests that

worker has performed and the total number of bytes served by

the worker (*)</li>

<li>A total number of accesses and byte count served (*)</li>

<li>The time the server was started/restarted and the time it

has been running for</li>

<li>Averages giving the number of requests per second, the

number of bytes served per second and the average number of

bytes per request (*)</li>

<li>The current percentage CPU used by each worker and in

total by all workers combined (*)</li>

<li>The current hosts and requests being processed (*)</li>

</ul>

<p>The lines marked "(*)" are only available if

<directive module="core">ExtendedStatus</directive>

is <code>On</code>. In version 2.3.6, loading mod_status will

toggle <directive module="core">ExtendedStatus</directive> On

by default.</p>

</summary>

<section id="enable">

<title>Enabling Status Support</title>

<p>To enable status reports only for browsers from the example.com

domain add this code to your <code>httpd.conf</code>

configuration file</p>

<highlight language="config">

&lt;Location "/server-status"&gt;

SetHandler server-status

Require host example.com

&lt;/Location&gt;

</highlight>

<p>You can now access server statistics by using a Web browser

to access the page

<code>http://your.server.name/server-status</code></p>

</section>

<section id="autoupdate">

<title>Automatic Updates</title>

<p>You can get the status page to update itself automatically if

you have a browser that supports "refresh". Access the page

<code>http://your.server.name/server-status?refresh=N</code> to

refresh the page every N seconds.</p>

</section>

<section id="machinereadable">

<title>Machine Readable Status File</title>

<p>A machine-readable version of the status file is available by

accessing the page

<code>http://your.server.name/server-status?auto</code>. This

is useful when automatically run, see the Perl program

<code>log_server_status</code>, which you will find in the

<code>/support</code> directory of your Apache HTTP Server installation.</p>

<note>

<strong>It should be noted that if <module>mod_status</module> is

loaded into the server, its handler capability is available

in <em>all</em> configuration files, including

<em>per</em>-directory files (<em>e.g.</em>,

<code>.htaccess</code>). This may have security-related

ramifications for your site.</strong>

</note>

</section>

<section id="troubleshoot">

<title>Using server-status to troubleshoot</title>

<p>The <code>server-status</code> page may be used as a starting

place for troubleshooting a situation where your server is consuming

all available resources (CPU or memory), and you wish to identify

which requests or clients are causing the problem.</p>

<p>First, ensure that you have <directive

module="core">ExtendedStatus</directive> set on, so that you can see

the full request and client information for each child or

thread.</p>

<p>Now look in your process list (using <code>top</code>, or similar

process viewing utility) to identify the specific processes that are

the main culprits. Order the output of <code>top</code> by CPU

usage, or memory usage, depending on what problem you're trying to

address.</p>

<p>Reload the <code>server-status</code> page, and look for those process

ids, and you'll be able to see what request is being served by that

process, for what client. Requests are transient, so you may need to

try several times before you catch it in the act, so to speak.</p>

<p>This process <em>should</em> give you some idea what client, or

what type of requests, are primarily responsible for your load

problems. Often you will identify a particular web application that

is misbehaving, or a particular client that is attacking your

site.</p>

</section>

</modulesynopsis>