granicus.if.org Git - apache/blob - docs/manual/mod/mod_heartbeat.html.en

   1 <?xml version="1.0" encoding="ISO-8859-1"?>
   2 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
   3 <html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en"><head><!--
   4         XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
   5               This file is generated from xml source: DO NOT EDIT
   6         XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
   7       -->
   8 <title>mod_heartbeat - Apache HTTP Server</title>
   9 <link href="../style/css/manual.css" rel="stylesheet" media="all" type="text/css" title="Main stylesheet" />
  10 <link href="../style/css/manual-loose-100pc.css" rel="alternate stylesheet" media="all" type="text/css" title="No Sidebar - Default font size" />
  11 <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" />
  12 <script src="../style/scripts/prettify.js" type="text/javascript">
  13 </script>
  14
  15 <link href="../images/favicon.ico" rel="shortcut icon" /></head>
  16 <body>
  17 <div id="page-header">
  18 <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>
  19 <p class="apache">Apache HTTP Server Version 2.5</p>
  20 <img alt="" src="../images/feather.gif" /></div>
  21 <div class="up"><a href="./"><img title="&lt;-" alt="&lt;-" src="../images/left.gif" /></a></div>
  22 <div id="path">
  23 <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="./">Modules</a></div>
  24 <div id="page-content">
  25 <div id="preamble"><h1>Apache Module mod_heartbeat</h1>
  26 <div class="toplang">
  27 <p><span>Available Languages: </span><a href="../en/mod/mod_heartbeat.html" title="English">&nbsp;en&nbsp;</a></p>
  28 </div>
  29 <table class="module"><tr><th><a href="module-dict.html#Description">Description:</a></th><td>Sends messages with server status to frontend proxy</td></tr>
  30 <tr><th><a href="module-dict.html#Status">Status:</a></th><td>Experimental</td></tr>
  31 <tr><th><a href="module-dict.html#ModuleIdentifier">Module Identifier:</a></th><td>heartbeat_module</td></tr>
  32 <tr><th><a href="module-dict.html#SourceFile">Source File:</a></th><td>mod_heartbeat</td></tr>
  33 <tr><th><a href="module-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 2.3 and later</td></tr></table>
  34 <h3>Summary</h3>
  35
  36 <p> <code class="module"><a href="../mod/mod_heartbeat.html">mod_heartbeat</a></code> sends multicast messages to a <code class="module"><a href="../mod/mod_heartmonitor.html">mod_heartmonitor</a></code> listener
  37 that advertises the servers current connection count.  Usually, <code class="module"><a href="../mod/mod_heartmonitor.html">mod_heartmonitor</a></code>
  38 will be running on a proxy server with <code class="module"><a href="../mod/mod_lbmethod_heartbeat.html">mod_lbmethod_heartbeat</a></code> loaded, which allows
  39 <code class="directive"><a href="../mod/mod_proxy.html#proxypass">ProxyPass</a></code> to use the "heartbeat" <em>lbmethod</em> inside
  40 of <code class="directive"><a href="../mod/mod_proxy.html#proxypass">ProxyPass</a></code>.</p>
  41 <p>
  42     <code class="module"><a href="../mod/mod_heartbeat.html">mod_heartbeat</a></code> itself is loaded on the origin server(s) that serve requests
  43     through the proxy server(s).
  44 </p>
  45
  46     <div class="warning">
  47         To use <code class="module"><a href="../mod/mod_heartbeat.html">mod_heartbeat</a></code>,
  48         <code class="module"><a href="../mod/mod_status.html">mod_status</a></code> and <code class="module"><a href="../mod/mod_watchdog.html">mod_watchdog</a></code>
  49         must be either a static modules or, if a dynamic module, must
  50         be loaded before <code class="module"><a href="../mod/mod_heartbeat.html">mod_heartbeat</a></code>.
  51     </div>
  52
  53 </div>
  54 <div id="quickview"><h3 class="directives">Directives</h3>
  55 <ul id="toc">
  56 <li><img alt="" src="../images/down.gif" /> <a href="#heartbeataddress">HeartbeatAddress</a></li>
  57 </ul>
  58 <h3>Topics</h3>
  59 <ul id="topics">
  60 <li><img alt="" src="../images/down.gif" /> <a href="#consuming">Consuming mod_heartbeat Output</a></li>
  61 </ul><ul class="seealso"><li><a href="#comments_section">Comments</a></li></ul></div>
  62 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
  63 <div class="section">
  64 <h2><a name="consuming" id="consuming">Consuming mod_heartbeat Output</a></h2>
  65
  66   <p>
  67       Every 1 second, this module generates a single multicast UDP
  68       packet, containing the number of busy and idle workers.  The
  69       packet is a simple ASCII format, similar to GET query parameters
  70       in HTTP.
  71   </p>
  72
  73 <div class="example"><h3>An Example Packet</h3><p><code>
  74 v=1&amp;ready=75&amp;busy=0
  75 </code></p></div>
  76
  77   <p>
  78     Consumers should handle new variables besides busy and ready,
  79     separated by '&amp;', being added in the future.
  80   </p>
  81
  82 </div>
  83 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
  84 <div class="directive-section"><h2><a name="HeartbeatAddress" id="HeartbeatAddress">HeartbeatAddress</a> <a name="heartbeataddress" id="heartbeataddress">Directive</a></h2>
  85 <table class="directive">
  86 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Multicast address for heartbeat packets</td></tr>
  87 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>HeartbeatAddress <var>addr:port</var></code></td></tr>
  88 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>disabled</code></td></tr>
  89 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
  90 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr>
  91 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_heartbeat</td></tr>
  92 </table>
  93 <p>The <code class="directive">HeartbeatAddress</code> directive specifies the
  94 multicast address to which <code class="module"><a href="../mod/mod_heartbeat.html">mod_heartbeat</a></code> will send
  95 status information. This address will usually correspond to a configured
  96  <code class="directive"><a href="../mod/mod_heartmonitor.html#heartbeatlisten">HeartbeatListen</a></code> on a
  97 frontend proxy system.</p>
  98 <pre class="prettyprint lang-config">
  99 HeartbeatAddress 239.0.0.1:27999
 100 </pre>
 101
 102
 103 </div>
 104 </div>
 105 <div class="bottomlang">
 106 <p><span>Available Languages: </span><a href="../en/mod/mod_heartbeat.html" title="English">&nbsp;en&nbsp;</a></p>
 107 </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>
 108 <script type="text/javascript"><!--//--><![CDATA[//><!--
 109 var comments_shortname = 'httpd';
 110 var comments_identifier = 'http://httpd.apache.org/docs/trunk/mod/mod_heartbeat.html';
 111 (function(w, d) {
 112     if (w.location.hostname.toLowerCase() == "httpd.apache.org") {
 113         d.write('<div id="comments_thread"><\/div>');
 114         var s = d.createElement('script');
 115         s.type = 'text/javascript';
 116         s.async = true;
 117         s.src = 'https://comments.apache.org/show_comments.lua?site=' + comments_shortname + '&page=' + comments_identifier;
 118         (d.getElementsByTagName('head')[0] || d.getElementsByTagName('body')[0]).appendChild(s);
 119     }
 120     else {
 121         d.write('<div id="comments_thread">Comments are disabled for this page at the moment.<\/div>');
 122     }
 123 })(window, document);
 124 //--><!]]></script></div><div id="footer">
 125 <p class="apache">Copyright 2013 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>
 126 <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[//><!--
 127 if (typeof(prettyPrint) !== 'undefined') {
 128     prettyPrint();
 129 }
 130 //--><!]]></script>
 131 </body></html>