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<title>logresolve - Resolve IP-addresses to hostnames in Apache
   log files - Apache HTTP Server Version 2.4</title>
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   log files</h1>
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     <p><code>logresolve</code> is a post-processing program to
     resolve IP-addresses in Apache's access logfiles.  To minimize
     impact on your nameserver, logresolve has its very own internal
     hash-table cache.  This means that each IP number will only be
     looked up the first time it is found in the log file.</p>

     <p>Takes an Apache log file on standard input.  The IP addresses
     must be the first thing on each line and must be separated from
     the remainder of the line by a space.</p>
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<li><img alt="" src="../images/down.gif" /> <a href="#options">Options</a></li>
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<h2><a name="synopsis" id="synopsis">Synopsis</a></h2>

     <p><code><strong>logresolve</strong> [ -<strong>s</strong>
     <var>filename</var> ] [ -<strong>c</strong> ] &lt;
     <var>access_log</var> &gt; <var>access_log.new</var></code></p>
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<h2><a name="options" id="options">Options</a></h2>

<dl>

<dt><code>-s <var>filename</var></code></dt>

<dd>Specifies a filename to record statistics.</dd>

<dt><code>-c</code></dt>

<dd>This causes <code>logresolve</code> to apply some DNS checks:
after finding the hostname from the IP address, it looks up the IP
addresses for the hostname and checks that one of these matches the
original address.</dd>

</dl>
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