summaryrefslogtreecommitdiffstats
path: root/docs/manual/mod/mod_heartbeat.html.en
blob: 5552abc15f70e78bccf6d11069afde189e2a61fa (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
<?xml version="1.0" encoding="ISO-8859-1"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en"><head>
<meta content="text/html; charset=ISO-8859-1" http-equiv="Content-Type" />
<!--
        XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
              This file is generated from xml source: DO NOT EDIT
        XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
      -->
<title>mod_heartbeat - Apache HTTP Server Version 2.4</title>
<link href="../style/css/manual.css" rel="stylesheet" media="all" type="text/css" title="Main stylesheet" />
<link href="../style/css/manual-loose-100pc.css" rel="alternate stylesheet" media="all" type="text/css" title="No Sidebar - Default font size" />
<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" />
<script src="../style/scripts/prettify.min.js" type="text/javascript">
</script>

<link href="../images/favicon.ico" rel="shortcut icon" /></head>
<body>
<div id="page-header">
<p class="menu"><a href="../mod/">Modules</a> | <a href="../mod/directives.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>
<p class="apache">Apache HTTP Server Version 2.4</p>
<img alt="" src="../images/feather.png" /></div>
<div class="up"><a href="./"><img title="&lt;-" alt="&lt;-" src="../images/left.gif" /></a></div>
<div id="path">
<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 2.4</a> &gt; <a href="./">Modules</a></div>
<div id="page-content">
<div id="preamble"><h1>Apache Module mod_heartbeat</h1>
<div class="toplang">
<p><span>Available Languages: </span><a href="../en/mod/mod_heartbeat.html" title="English">&nbsp;en&nbsp;</a> |
<a href="../fr/mod/mod_heartbeat.html" hreflang="fr" rel="alternate" title="Fran�ais">&nbsp;fr&nbsp;</a></p>
</div>
<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>
<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>heartbeat_module</td></tr>
<tr><th><a href="module-dict.html#SourceFile">Source�File:</a></th><td>mod_heartbeat</td></tr>
<tr><th><a href="module-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 2.3 and later</td></tr></table>
<h3>Summary</h3>

<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 
that advertises the servers current connection count.  Usually, <code class="module"><a href="../mod/mod_heartmonitor.html">mod_heartmonitor</a></code>
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
<code class="directive"><a href="../mod/mod_proxy.html#proxypass">ProxyPass</a></code> to use the "heartbeat" <em>lbmethod</em> inside
of <code class="directive"><a href="../mod/mod_proxy.html#proxypass">ProxyPass</a></code>.</p>
<p>
    <code class="module"><a href="../mod/mod_heartbeat.html">mod_heartbeat</a></code> itself is loaded on the origin server(s) that serve requests 
    through the proxy server(s).  
</p>

    <div class="warning">
        To use <code class="module"><a href="../mod/mod_heartbeat.html">mod_heartbeat</a></code>,
        <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>
        must be either a static modules or, if a dynamic module, must
        be loaded before <code class="module"><a href="../mod/mod_heartbeat.html">mod_heartbeat</a></code>.
    </div>

</div>
<div id="quickview"><a href="https://www.apache.org/foundation/contributing.html" class="badge"><img src="https://www.apache.org/images/SupportApache-small.png" alt="Support Apache!" /></a><h3>Topics</h3>
<ul id="topics">
<li><img alt="" src="../images/down.gif" /> <a href="#consuming">Consuming mod_heartbeat Output</a></li>
</ul><h3 class="directives">Directives</h3>
<ul id="toc">
<li><img alt="" src="../images/down.gif" /> <a href="#heartbeataddress">HeartbeatAddress</a></li>
</ul>
<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_heartbeat">Known issues</a></li><li><a href="https://bz.apache.org/bugzilla/enter_bug.cgi?product=Apache%20httpd-2&amp;component=mod_heartbeat">Report a bug</a></li></ul><h3>See also</h3>
<ul class="seealso">
<li><a href="#comments_section">Comments</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="consuming" id="consuming">Consuming mod_heartbeat Output</a></h2>
    
  <p>
      Every 1 second, this module generates a single multicast UDP
      packet, containing the number of busy and idle workers.  The
      packet is a simple ASCII format, similar to GET query parameters
      in HTTP.
  </p>
  
<div class="example"><h3>An Example Packet</h3><p><code>
v=1&amp;ready=75&amp;busy=0
</code></p></div>

  <p>
    Consumers should handle new variables besides busy and ready,
    separated by '&amp;', being added in the future.
  </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="HeartbeatAddress" id="HeartbeatAddress">HeartbeatAddress</a> <a name="heartbeataddress" id="heartbeataddress">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Multicast address for heartbeat packets</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>HeartbeatAddress <var>addr:port</var></code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>disabled</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_heartbeat</td></tr>
</table>
<p>The <code class="directive">HeartbeatAddress</code> directive specifies the
multicast address to which <code class="module"><a href="../mod/mod_heartbeat.html">mod_heartbeat</a></code> will send
status information. This address will usually correspond to a configured
 <code class="directive"><a href="../mod/mod_heartmonitor.html#heartbeatlisten">HeartbeatListen</a></code> on a
frontend proxy system.</p>
<pre class="prettyprint lang-config">HeartbeatAddress 239.0.0.1:27999</pre>
    

</div>
</div>
<div class="bottomlang">
<p><span>Available Languages: </span><a href="../en/mod/mod_heartbeat.html" title="English">&nbsp;en&nbsp;</a> |
<a href="../fr/mod/mod_heartbeat.html" hreflang="fr" rel="alternate" title="Fran�ais">&nbsp;fr&nbsp;</a></p>
</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>
<script type="text/javascript"><!--//--><![CDATA[//><!--
var comments_shortname = 'httpd';
var comments_identifier = 'http://httpd.apache.org/docs/2.4/mod/mod_heartbeat.html';
(function(w, d) {
    if (w.location.hostname.toLowerCase() == "httpd.apache.org") {
        d.write('<div id="comments_thread"><\/div>');
        var s = d.createElement('script');
        s.type = 'text/javascript';
        s.async = true;
        s.src = 'https://comments.apache.org/show_comments.lua?site=' + comments_shortname + '&page=' + comments_identifier;
        (d.getElementsByTagName('head')[0] || d.getElementsByTagName('body')[0]).appendChild(s);
    }
    else { 
        d.write('<div id="comments_thread">Comments are disabled for this page at the moment.<\/div>');
    }
})(window, document);
//--><!]]></script></div><div id="footer">
<p class="apache">Copyright 2019 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>
<p class="menu"><a href="../mod/">Modules</a> | <a href="../mod/directives.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[//><!--
if (typeof(prettyPrint) !== 'undefined') {
    prettyPrint();
}
//--><!]]></script>
</body></html>