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<div id="preamble"><h1>Apache Module mod_ratelimit</h1>
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<table class="module"><tr><th><a href="module-dict.html#Description">Description:</a></th><td>Bandwidth Rate Limiting for Clients</td></tr>
<tr><th><a href="module-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="module-dict.html#ModuleIdentifier">Module&nbsp;Identifier:</a></th><td>ratelimit_module</td></tr>
<tr><th><a href="module-dict.html#SourceFile">Source&nbsp;File:</a></th><td>mod_ratelimit.c</td></tr>
<tr><th><a href="module-dict.html#Compatibility">Compatibility:</a></th><td>
    <code>rate-initial-burst</code> available in httpd 2.4.24 and later.
    Rate limiting proxied content does not work correctly up to httpd 2.4.33.
</td></tr></table>
<h3>Summary</h3>


<p>Provides a filter named <code>RATE_LIMIT</code> to limit client bandwidth.
The throttling is applied to each HTTP response while it is transferred to the client,
and not aggregated at IP/client level.
The connection speed to be simulated is specified, in KiB/s, using the environment
variable <code>rate-limit</code>.</p>

<p>Optionally, an initial amount of burst data, in KiB, may be
configured to be passed at full speed before throttling to the
specified rate limit.  This value is optional, and is set using
the environment variable <code>rate-initial-burst</code>.</p>

<div class="example"><h3>Example Configuration</h3><pre class="prettyprint lang-config">&lt;Location "/downloads"&gt;
    SetOutputFilter RATE_LIMIT
    SetEnv rate-limit 400 
    SetEnv rate-initial-burst 512
&lt;/Location&gt;</pre>
<div class="warning">
If the value specified for <code>rate-limit</code> causes integer overflow, the rate-limited will be disabled.
If the value specified for <code>rate-limit-burst</code> causes integer overflow, the burst will be disabled.
</div></div>

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<div id="quickview"><h3 class="directives">Directives</h3>
<p>This module provides no
            directives.</p>
<h3>Bugfix checklist</h3><ul class="seealso"><li><a href="https://www.apache.org/dist/httpd/CHANGES_2.4">httpd changelog</a></li><li><a href="https://bz.apache.org/bugzilla/buglist.cgi?bug_status=__open__&amp;list_id=144532&amp;product=Apache%20httpd-2&amp;query_format=specific&amp;order=changeddate%20DESC%2Cpriority%2Cbug_severity&amp;component=mod_ratelimit">Known issues</a></li><li><a href="https://bz.apache.org/bugzilla/enter_bug.cgi?product=Apache%20httpd-2&amp;component=mod_ratelimit">Report a bug</a></li></ul></div>

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