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 <p class="apache">Apache HTTP Server Version 2.0</p>
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 <div id="page-content">
 <div id="preamble"><h1>Apache Module mod_ldap</h1>
 <table class="module"><tr><th><a href="module-dict.html#Description">Description:</a></th><td>LDAP connection pooling and result caching services for use
 by other LDAP modules</td></tr>
 <tr><th><a href="module-dict.html#Status">Status:</a></th><td>Experimental</td></tr>
 <tr><th><a href="module-dict.html#ModuleIdentifier">Module Identifier:</a></th><td>ldap_module</td></tr>
 <tr><th><a href="module-dict.html#SourceFile">Source File:</a></th><td>util_ldap.c</td></tr>
 <tr><th><a href="module-dict.html#Compatibility">Compatibility:</a></th><td>Available in version 2.0.41 and later</td></tr></table>
 <h3>Summary</h3>

     <p>This module was created to improve the performance of
     websites relying on backend connections to LDAP servers. In
     addition to the functions provided by the standard LDAP
     libraries, this module adds an LDAP connection pool and an LDAP
     shared memory cache.</p>

     <p>To enable this module, LDAP support must be compiled into
     apr-util. This is achieved by adding the <code>--with-ldap</code>
     flag to the <code>./configure</code> script when building
     Apache.</p>
 </div>
 <div id="quickview"><h3 class="directives">Directives</h3>
 <ul id="toc">
 <li><img alt="" src="../images/down.gif" /> <a href="#ldapcacheentries">LDAPCacheEntries</a></li>
 <li><img alt="" src="../images/down.gif" /> <a href="#ldapcachettl">LDAPCacheTTL</a></li>
 <li><img alt="" src="../images/down.gif" /> <a href="#ldapcertdbpath">LDAPCertDBPath</a></li>
 <li><img alt="" src="../images/down.gif" /> <a href="#ldapopcacheentries">LDAPOpCacheEntries</a></li>
 <li><img alt="" src="../images/down.gif" /> <a href="#ldapopcachettl">LDAPOpCacheTTL</a></li>
 <li><img alt="" src="../images/down.gif" /> <a href="#ldapsharedcachesize">LDAPSharedCacheSize</a></li>
 </ul>
 <h3>Topics</h3>
 <ul id="topics">
 <li><img alt="" src="../images/down.gif" /> <a href="#exampleconfig">Example Configuration</a></li>
 <li><img alt="" src="../images/down.gif" /> <a href="#pool">LDAP Connection Pool</a></li>
 <li><img alt="" src="../images/down.gif" /> <a href="#cache">LDAP Cache</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="exampleconfig" id="exampleconfig">Example Configuration</a></h2>
     <p>The following is an example configuration that uses
     <code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> to increase the performance of HTTP Basic
     authentication provided by <code class="module"><a href="../mod/mod_auth_ldap.html">mod_auth_ldap</a></code>.</p>

     <div class="example"><p><code>
       # Enable the LDAP connection pool and shared<br />
       # memory cache. Enable the LDAP cache status<br />
       # handler. Requires that mod_ldap and mod_auth_ldap<br />
       # be loaded. Change the "yourdomain.example.com" to<br />
       # match your domain.<br />
       <br />
       LDAPSharedCacheSize 200000<br />
       LDAPCacheEntries 1024<br />
       LDAPCacheTTL 600<br />
       LDAPOpCacheEntries 1024<br />
       LDAPOpCacheTTL 600<br />
       <br />
       &lt;Location /ldap-status&gt;<br />
       <span class="indent">
         SetHandler ldap-status<br />
         Order deny,allow<br />
         Deny from all<br />
         Allow from yourdomain.example.com<br />
         AuthLDAPEnabled on<br />
         AuthLDAPURL ldap://127.0.0.1/dc=example,dc=com?uid?one<br />
         AuthLDAPAuthoritative on<br />
         require valid-user<br />
       </span>
       &lt;/Location&gt;
     </code></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="pool" id="pool">LDAP Connection Pool</a></h2>

     <p>LDAP connections are pooled from request to request. This
     allows the LDAP server to remain connected and bound ready for
     the next request, without the need to unbind/connect/rebind.
     The performance advantages are similar to the effect of HTTP
     keepalives.</p>

     <p>On a busy server it is possible that many requests will try
     and access the same LDAP server connection simultaneously.
     Where an LDAP connection is in use, Apache will create a new
     connection alongside the original one. This ensures that the
     connection pool does not become a bottleneck.</p>

     <p>There is no need to manually enable connection pooling in
     the Apache configuration. Any module using this module for
     access to LDAP services will share the connection pool.</p>
 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
 <div class="section">
 <h2><a name="cache" id="cache">LDAP Cache</a></h2>

     <p>For improved performance, <code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> uses an aggressive
     caching strategy to minimize the number of times that the LDAP
     server must be contacted. Caching can easily double or triple
     the throughput of Apache when it is serving pages protected
     with mod_auth_ldap. In addition, the load on the LDAP server
     will be significantly decreased.</p>

     <p><code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> supports two types of LDAP caching during
     the search/bind phase with a <em>search/bind cache</em> and
     during the compare phase with two <em>operation
     caches</em>. Each LDAP URL that is used by the server has
     its own set of these three caches.</p>

     <h3><a name="search-bind" id="search-bind">The Search/Bind Cache</a></h3>
       <p>The process of doing a search and then a bind is the
       most time-consuming aspect of LDAP operation, especially if
       the directory is large. The search/bind cache is used to
       cache all searches that resulted in successful binds.
       Negative results (<em>i.e.</em>, unsuccessful searches, or searches
       that did not result in a successful bind) are not cached.
       The rationale behind this decision is that connections with
       invalid credentials are only a tiny percentage of the total
       number of connections, so by not caching invalid
       credentials, the size of the cache is reduced.</p>

       <p><code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> stores the username, the DN
       retrieved, the password used to bind, and the time of the bind
       in the cache. Whenever a new connection is initiated with the
       same username, <code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> compares the password
       of the new connection with the password in the cache. If the
       passwords match, and if the cached entry is not too old,
       <code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> bypasses the search/bind phase.</p>

       <p>The search and bind cache is controlled with the <code class="directive"><a href="#ldapcacheentries">LDAPCacheEntries</a></code> and <code class="directive"><a href="#ldapcachettl">LDAPCacheTTL</a></code> directives.</p>


     <h3><a name="opcaches" id="opcaches">Operation Caches</a></h3>
       <p>During attribute and distinguished name comparison
       functions, <code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> uses two operation caches
       to cache the compare operations. The first compare cache is
       used to cache the results of compares done to test for LDAP
       group membership. The second compare cache is used to cache
       the results of comparisons done between distinguished
       names.</p>

       <p>The behavior of both of these caches is controlled with
       the <code class="directive"><a href="#ldapopcacheentries">LDAPOpCacheEntries</a></code>
       and <code class="directive"><a href="#ldapopcachettl">LDAPOpCacheTTL</a></code>
       directives.</p>


     <h3><a name="monitoring" id="monitoring">Monitoring the Cache</a></h3>
       <p><code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> has a content handler that allows
       administrators to monitor the cache performance. The name of
       the content handler is <code>ldap-status</code>, so the
       following directives could be used to access the
       <code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> cache information:</p>

       <div class="example"><p><code>
         &lt;Location /server/cache-info&gt;<br />
         <span class="indent">
           SetHandler ldap-status<br />
         </span>
         &lt;/Location&gt;
       </code></p></div>

       <p>By fetching the URL <code>http://servername/cache-info</code>,
       the administrator can get a status report of every cache that is used
       by <code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> cache. Note that if Apache does not
       support shared memory, then each <code>httpd</code> instance has its
       own cache, so reloading the URL will result in different
       information each time, depending on which <code>httpd</code>
       instance processes the request.</p>

 </div>
 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
 <div class="directive-section"><h2><a name="LDAPCacheEntries" id="LDAPCacheEntries">LDAPCacheEntries</a> <a name="ldapcacheentries" id="ldapcacheentries">Directive</a></h2>
 <table class="directive">
 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Maximum number of entires in the primary LDAP cache</td></tr>
 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LDAPCacheEntries <var>number</var></code></td></tr>
 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LDAPCacheEntries 1024</code></td></tr>
 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr>
 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ldap</td></tr>
 </table>
     <p>Specifies the maximum size of the primary LDAP cache. This
     cache contains successful search/binds. Set it to 0 to turn off
     search/bind caching. The default size is 1024 cached
     searches.</p>

 </div>
 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
 <div class="directive-section"><h2><a name="LDAPCacheTTL" id="LDAPCacheTTL">LDAPCacheTTL</a> <a name="ldapcachettl" id="ldapcachettl">Directive</a></h2>
 <table class="directive">
 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Time that cached items remain valid</td></tr>
 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LDAPCacheTTL <var>seconds</var></code></td></tr>
 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LDAPCacheTTL 600</code></td></tr>
 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr>
 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ldap</td></tr>
 </table>
     <p>Specifies the time (in seconds) that an item in the
     search/bind cache remains valid. The default is 600 seconds (10
     minutes).</p>

 </div>
 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
 <div class="directive-section"><h2><a name="LDAPCertDBPath" id="LDAPCertDBPath">LDAPCertDBPath</a> <a name="ldapcertdbpath" id="ldapcertdbpath">Directive</a></h2>
 <table class="directive">
 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Directory containing certificates for SSL support</td></tr>
 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LDAPCertDBPath <var>directory-path</var></code></td></tr>
 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr>
 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ldap</td></tr>
 </table>
     <p>This directive is only valid if Apache has been linked
     against the Netscape/iPlanet Directory SDK.</p>

     <p>It specifies in which directory <code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code>
     should look for the certificate authorities database for SSL
     support. There should be a file named <code>cert7.db</code> in that
     directory.</p>

 </div>
 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
 <div class="directive-section"><h2><a name="LDAPOpCacheEntries" id="LDAPOpCacheEntries">LDAPOpCacheEntries</a> <a name="ldapopcacheentries" id="ldapopcacheentries">Directive</a></h2>
 <table class="directive">
 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Number of entries used to cache LDAP compare
 operations</td></tr>
 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LDAPOpCacheEntries <var>number</var></code></td></tr>
 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LDAPOpCacheEntries 1024</code></td></tr>
 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr>
 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ldap</td></tr>
 </table>
     <p>This specifies the number of entries <code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code>
     will use to cache LDAP compare operations. The default is 1024
     entries.  Setting it to 0 disables operation caching.</p>

 </div>
 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
 <div class="directive-section"><h2><a name="LDAPOpCacheTTL" id="LDAPOpCacheTTL">LDAPOpCacheTTL</a> <a name="ldapopcachettl" id="ldapopcachettl">Directive</a></h2>
 <table class="directive">
 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Time that entries in the operation cache remain
 valid</td></tr>
 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LDAPOpCacheTTL <var>seconds</var></code></td></tr>
 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LDAPOpCacheTTL 600</code></td></tr>
 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr>
 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ldap</td></tr>
 </table>
     <p>Specifies the time (in seconds) that entries in the
     operation cache remain valid. The default is 600 seconds.</p>

 </div>
 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
 <div class="directive-section"><h2><a name="LDAPSharedCacheSize" id="LDAPSharedCacheSize">LDAPSharedCacheSize</a> <a name="ldapsharedcachesize" id="ldapsharedcachesize">Directive</a></h2>
 <table class="directive">
 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Size in bytes of the shared-memory cache</td></tr>
 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LDAPSharedCacheSize <var>bytes</var></code></td></tr>
 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LDAPSharedCacheSize 102400</code></td></tr>
 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr>
 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ldap</td></tr>
 </table>
     <p>Specifies the number of bytes to specify for the shared
     memory cache. The default is 100kb.</p>

 </div>
 </div>
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	<title>mod_ldap - Apache HTTP Server</title>
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	<img alt="" src="../images/feather.gif" /></div>
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	<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-project/">Documentation</a> > <a href="../">Version 2.0</a> > <a href="./">Modules</a></div>
	<div id="page-content">
	<div id="preamble"><h1>Apache Module mod_ldap</h1>
	<table class="module"><tr><th><a href="module-dict.html#Description">Description:</a></th><td>LDAP connection pooling and result caching services for use
	by other LDAP modules</td></tr>
	<tr><th><a href="module-dict.html#Status">Status:</a></th><td>Experimental</td></tr>
	<tr><th><a href="module-dict.html#ModuleIdentifier">Module Identifier:</a></th><td>ldap_module</td></tr>
	<tr><th><a href="module-dict.html#SourceFile">Source File:</a></th><td>util_ldap.c</td></tr>
	<tr><th><a href="module-dict.html#Compatibility">Compatibility:</a></th><td>Available in version 2.0.41 and later</td></tr></table>
	<h3>Summary</h3>

	<p>This module was created to improve the performance of
	websites relying on backend connections to LDAP servers. In
	addition to the functions provided by the standard LDAP
	libraries, this module adds an LDAP connection pool and an LDAP
	shared memory cache.</p>

	<p>To enable this module, LDAP support must be compiled into
	apr-util. This is achieved by adding the <code>--with-ldap</code>
	flag to the <code>./configure</code> script when building
	Apache.</p>
	</div>
	<div id="quickview"><h3 class="directives">Directives</h3>
	<ul id="toc">
	<li><img alt="" src="../images/down.gif" /> <a href="#ldapcacheentries">LDAPCacheEntries</a></li>
	<li><img alt="" src="../images/down.gif" /> <a href="#ldapcachettl">LDAPCacheTTL</a></li>
	<li><img alt="" src="../images/down.gif" /> <a href="#ldapcertdbpath">LDAPCertDBPath</a></li>
	<li><img alt="" src="../images/down.gif" /> <a href="#ldapopcacheentries">LDAPOpCacheEntries</a></li>
	<li><img alt="" src="../images/down.gif" /> <a href="#ldapopcachettl">LDAPOpCacheTTL</a></li>
	<li><img alt="" src="../images/down.gif" /> <a href="#ldapsharedcachesize">LDAPSharedCacheSize</a></li>
	</ul>
	<h3>Topics</h3>
	<ul id="topics">
	<li><img alt="" src="../images/down.gif" /> <a href="#exampleconfig">Example Configuration</a></li>
	<li><img alt="" src="../images/down.gif" /> <a href="#pool">LDAP Connection Pool</a></li>
	<li><img alt="" src="../images/down.gif" /> <a href="#cache">LDAP Cache</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="exampleconfig" id="exampleconfig">Example Configuration</a></h2>
	<p>The following is an example configuration that uses
	<code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> to increase the performance of HTTP Basic
	authentication provided by <code class="module"><a href="../mod/mod_auth_ldap.html">mod_auth_ldap</a></code>.</p>

	<div class="example"><p><code>
	# Enable the LDAP connection pool and shared<br />
	# memory cache. Enable the LDAP cache status<br />
	# handler. Requires that mod_ldap and mod_auth_ldap<br />
	# be loaded. Change the "yourdomain.example.com" to<br />
	# match your domain.<br />
	<br />
	LDAPSharedCacheSize 200000<br />
	LDAPCacheEntries 1024<br />
	LDAPCacheTTL 600<br />
	LDAPOpCacheEntries 1024<br />
	LDAPOpCacheTTL 600<br />
	<br />
	<Location /ldap-status><br />
	<span class="indent">
	SetHandler ldap-status<br />
	Order deny,allow<br />
	Deny from all<br />
	Allow from yourdomain.example.com<br />
	AuthLDAPEnabled on<br />
	AuthLDAPURL ldap://127.0.0.1/dc=example,dc=com?uid?one<br />
	AuthLDAPAuthoritative on<br />
	require valid-user<br />
	</span>
	</Location>
	</code></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="pool" id="pool">LDAP Connection Pool</a></h2>

	<p>LDAP connections are pooled from request to request. This
	allows the LDAP server to remain connected and bound ready for
	the next request, without the need to unbind/connect/rebind.
	The performance advantages are similar to the effect of HTTP
	keepalives.</p>

	<p>On a busy server it is possible that many requests will try
	and access the same LDAP server connection simultaneously.
	Where an LDAP connection is in use, Apache will create a new
	connection alongside the original one. This ensures that the
	connection pool does not become a bottleneck.</p>

	<p>There is no need to manually enable connection pooling in
	the Apache configuration. Any module using this module for
	access to LDAP services will share the connection pool.</p>
	</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
	<div class="section">
	<h2><a name="cache" id="cache">LDAP Cache</a></h2>

	<p>For improved performance, <code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> uses an aggressive
	caching strategy to minimize the number of times that the LDAP
	server must be contacted. Caching can easily double or triple
	the throughput of Apache when it is serving pages protected
	with mod_auth_ldap. In addition, the load on the LDAP server
	will be significantly decreased.</p>

	<p><code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> supports two types of LDAP caching during
	the search/bind phase with a <em>search/bind cache</em> and
	during the compare phase with two <em>operation
	caches</em>. Each LDAP URL that is used by the server has
	its own set of these three caches.</p>

	<h3><a name="search-bind" id="search-bind">The Search/Bind Cache</a></h3>
	<p>The process of doing a search and then a bind is the
	most time-consuming aspect of LDAP operation, especially if
	the directory is large. The search/bind cache is used to
	cache all searches that resulted in successful binds.
	Negative results (<em>i.e.</em>, unsuccessful searches, or searches
	that did not result in a successful bind) are not cached.
	The rationale behind this decision is that connections with
	invalid credentials are only a tiny percentage of the total
	number of connections, so by not caching invalid
	credentials, the size of the cache is reduced.</p>

	<p><code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> stores the username, the DN
	retrieved, the password used to bind, and the time of the bind
	in the cache. Whenever a new connection is initiated with the
	same username, <code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> compares the password
	of the new connection with the password in the cache. If the
	passwords match, and if the cached entry is not too old,
	<code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> bypasses the search/bind phase.</p>

	<p>The search and bind cache is controlled with the <code class="directive"><a href="#ldapcacheentries">LDAPCacheEntries</a></code> and <code class="directive"><a href="#ldapcachettl">LDAPCacheTTL</a></code> directives.</p>


	<h3><a name="opcaches" id="opcaches">Operation Caches</a></h3>
	<p>During attribute and distinguished name comparison
	functions, <code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> uses two operation caches
	to cache the compare operations. The first compare cache is
	used to cache the results of compares done to test for LDAP
	group membership. The second compare cache is used to cache
	the results of comparisons done between distinguished
	names.</p>

	<p>The behavior of both of these caches is controlled with
	the <code class="directive"><a href="#ldapopcacheentries">LDAPOpCacheEntries</a></code>
	and <code class="directive"><a href="#ldapopcachettl">LDAPOpCacheTTL</a></code>
	directives.</p>


	<h3><a name="monitoring" id="monitoring">Monitoring the Cache</a></h3>
	<p><code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> has a content handler that allows
	administrators to monitor the cache performance. The name of
	the content handler is <code>ldap-status</code>, so the
	following directives could be used to access the
	<code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> cache information:</p>

	<div class="example"><p><code>
	<Location /server/cache-info><br />
	<span class="indent">
	SetHandler ldap-status<br />
	</span>
	</Location>
	</code></p></div>

	<p>By fetching the URL <code>http://servername/cache-info</code>,
	the administrator can get a status report of every cache that is used
	by <code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> cache. Note that if Apache does not
	support shared memory, then each <code>httpd</code> instance has its
	own cache, so reloading the URL will result in different
	information each time, depending on which <code>httpd</code>
	instance processes the request.</p>

	</div>
	<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
	<div class="directive-section"><h2><a name="LDAPCacheEntries" id="LDAPCacheEntries">LDAPCacheEntries</a> <a name="ldapcacheentries" id="ldapcacheentries">Directive</a></h2>
	<table class="directive">
	<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Maximum number of entires in the primary LDAP cache</td></tr>
	<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LDAPCacheEntries <var>number</var></code></td></tr>
	<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LDAPCacheEntries 1024</code></td></tr>
	<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
	<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr>
	<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ldap</td></tr>
	</table>
	<p>Specifies the maximum size of the primary LDAP cache. This
	cache contains successful search/binds. Set it to 0 to turn off
	search/bind caching. The default size is 1024 cached
	searches.</p>

	</div>
	<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
	<div class="directive-section"><h2><a name="LDAPCacheTTL" id="LDAPCacheTTL">LDAPCacheTTL</a> <a name="ldapcachettl" id="ldapcachettl">Directive</a></h2>
	<table class="directive">
	<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Time that cached items remain valid</td></tr>
	<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LDAPCacheTTL <var>seconds</var></code></td></tr>
	<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LDAPCacheTTL 600</code></td></tr>
	<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
	<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr>
	<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ldap</td></tr>
	</table>
	<p>Specifies the time (in seconds) that an item in the
	search/bind cache remains valid. The default is 600 seconds (10
	minutes).</p>

	</div>
	<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
	<div class="directive-section"><h2><a name="LDAPCertDBPath" id="LDAPCertDBPath">LDAPCertDBPath</a> <a name="ldapcertdbpath" id="ldapcertdbpath">Directive</a></h2>
	<table class="directive">
	<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Directory containing certificates for SSL support</td></tr>
	<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LDAPCertDBPath <var>directory-path</var></code></td></tr>
	<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
	<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr>
	<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ldap</td></tr>
	</table>
	<p>This directive is only valid if Apache has been linked
	against the Netscape/iPlanet Directory SDK.</p>

	<p>It specifies in which directory <code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code>
	should look for the certificate authorities database for SSL
	support. There should be a file named <code>cert7.db</code> in that
	directory.</p>

	</div>
	<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
	<div class="directive-section"><h2><a name="LDAPOpCacheEntries" id="LDAPOpCacheEntries">LDAPOpCacheEntries</a> <a name="ldapopcacheentries" id="ldapopcacheentries">Directive</a></h2>
	<table class="directive">
	<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Number of entries used to cache LDAP compare
	operations</td></tr>
	<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LDAPOpCacheEntries <var>number</var></code></td></tr>
	<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LDAPOpCacheEntries 1024</code></td></tr>
	<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
	<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr>
	<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ldap</td></tr>
	</table>
	<p>This specifies the number of entries <code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code>
	will use to cache LDAP compare operations. The default is 1024
	entries. Setting it to 0 disables operation caching.</p>

	</div>
	<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
	<div class="directive-section"><h2><a name="LDAPOpCacheTTL" id="LDAPOpCacheTTL">LDAPOpCacheTTL</a> <a name="ldapopcachettl" id="ldapopcachettl">Directive</a></h2>
	<table class="directive">
	<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Time that entries in the operation cache remain
	valid</td></tr>
	<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LDAPOpCacheTTL <var>seconds</var></code></td></tr>
	<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LDAPOpCacheTTL 600</code></td></tr>
	<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
	<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr>
	<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ldap</td></tr>
	</table>
	<p>Specifies the time (in seconds) that entries in the
	operation cache remain valid. The default is 600 seconds.</p>

	</div>
	<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
	<div class="directive-section"><h2><a name="LDAPSharedCacheSize" id="LDAPSharedCacheSize">LDAPSharedCacheSize</a> <a name="ldapsharedcachesize" id="ldapsharedcachesize">Directive</a></h2>
	<table class="directive">
	<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Size in bytes of the shared-memory cache</td></tr>
	<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LDAPSharedCacheSize <var>bytes</var></code></td></tr>
	<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LDAPSharedCacheSize 102400</code></td></tr>
	<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
	<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr>
	<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ldap</td></tr>
	</table>
	<p>Specifies the number of bytes to specify for the shared
	memory cache. The default is 100kb.</p>

	</div>
	</div>
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