78 lines
5.7 KiB
HTML
78 lines
5.7 KiB
HTML
<?xml version="1.0" encoding="UTF-8"?>
|
|
<!DOCTYPE html
|
|
PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
|
|
<html lang="en-us" xml:lang="en-us">
|
|
<head>
|
|
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
|
|
<meta name="security" content="public" />
|
|
<meta name="Robots" content="index,follow" />
|
|
<meta http-equiv="PICS-Label" content='(PICS-1.1 "http://www.icra.org/ratingsv02.html" l gen true r (cz 1 lz 1 nz 1 oz 1 vz 1) "http://www.rsac.org/ratingsv01.html" l gen true r (n 0 s 0 v 0 l 0) "http://www.classify.org/safesurf/" l gen true r (SS~~000 1))' />
|
|
<meta name="DC.Type" content="concept" />
|
|
<meta name="DC.Title" content="Heartbeat monitoring" />
|
|
<meta name="abstract" content="Heartbeat monitoring is a cluster resource services function that ensures that each node is active by sending a signal from every node in the cluster to every other node in the cluster to convey that they are still active." />
|
|
<meta name="description" content="Heartbeat monitoring is a cluster resource services function that ensures that each node is active by sending a signal from every node in the cluster to every other node in the cluster to convey that they are still active." />
|
|
<meta name="DC.Relation" scheme="URI" content="rzaigconceptsevents.htm" />
|
|
<meta name="DC.Relation" scheme="URI" content="rzaigmanage.htm" />
|
|
<meta name="DC.Relation" scheme="URI" content="rzaigmanagemonitor.htm" />
|
|
<meta name="DC.Relation" scheme="URI" content="rzaigmanageclusterperformance.htm" />
|
|
<meta name="copyright" content="(C) Copyright IBM Corporation 1998, 2006" />
|
|
<meta name="DC.Rights.Owner" content="(C) Copyright IBM Corporation 1998, 2006" />
|
|
<meta name="DC.Format" content="XHTML" />
|
|
<meta name="DC.Identifier" content="rzaigconceptsheartbeatmonitor" />
|
|
<meta name="DC.Language" content="en-us" />
|
|
<!-- All rights reserved. Licensed Materials Property of IBM -->
|
|
<!-- US Government Users Restricted Rights -->
|
|
<!-- Use, duplication or disclosure restricted by -->
|
|
<!-- GSA ADP Schedule Contract with IBM Corp. -->
|
|
<link rel="stylesheet" type="text/css" href="./ibmdita.css" />
|
|
<link rel="stylesheet" type="text/css" href="./ic.css" />
|
|
<title>Heartbeat monitoring</title>
|
|
</head>
|
|
<body id="rzaigconceptsheartbeatmonitor"><a name="rzaigconceptsheartbeatmonitor"><!-- --></a>
|
|
<!-- Java sync-link --><script language="Javascript" src="../rzahg/synch.js" type="text/javascript"></script>
|
|
<h1 class="topictitle1">Heartbeat monitoring</h1>
|
|
<div><p><dfn class="term">Heartbeat monitoring</dfn> is a cluster resource services
|
|
function that ensures that each node is active by sending a signal from every
|
|
node in the cluster to every other node in the cluster to convey that they
|
|
are still active.</p>
|
|
<p><img src="./delta.gif" alt="Start of change" />When the heartbeat for a node fails, cluster resource services
|
|
takes the appropriate action.<img src="./deltaend.gif" alt="End of change" /></p>
|
|
<p>Consider the following examples to understand how heartbeat monitoring
|
|
works:</p>
|
|
<div class="section"><h4 class="sectiontitle">Example 1</h4><br /><img src="rv4c102.gif" alt="Heartbeat monitor example." /><br /><p>With the default (or normal) settings, a heartbeat
|
|
message is sent every 3 seconds from every node in the cluster to its upstream
|
|
neighbor. For example, if you configure Node A, Node B, and Node C on Network
|
|
1, Node A sends a message to Node B, Node B sends a message to Node C, and
|
|
Node C sends a message to Node A. Node A expects an acknowledgment to the
|
|
heartbeat from Node B as well as an incoming heartbeat from the downstream
|
|
Node C. In effect, the heartbeating ring goes both ways. If Node A did not
|
|
receive a heartbeat from Node C, Node A and Node B continues to send a heartbeat
|
|
every 3 seconds. If Node C missed four consecutive heartbeats, a heartbeat
|
|
failure is signaled.</p>
|
|
</div>
|
|
<div class="section"><h4 class="sectiontitle">Example 2</h4><img src="rv4c101.gif" alt="Heartbeat monitor with routers example." /><p>Let's add another network to this example to
|
|
show how routers and relay nodes are used. You configure Node D, Node E, and
|
|
Node F on Network 2. Network 2 is connected to Network 1 using a router. A
|
|
router can be another iSeries™ server or a router box that directs communications
|
|
to another router somewhere else. Every local network is assigned a relay
|
|
node. This relay node is assigned to the node that has the lowest node ID
|
|
in the network. Node A is assigned as the relay node on Network 1, and Node
|
|
D is assigned as the relay node on Network 2. A logical network containing
|
|
Node A and Node D is then created. By using routers and relay nodes, the nodes
|
|
on these two networks can monitor each other and signal any node failures.</p>
|
|
</div>
|
|
</div>
|
|
<div>
|
|
<div class="familylinks">
|
|
<div class="parentlink"><strong>Parent topic:</strong> <img src="./delta.gif" alt="Start of change" /><a href="rzaigconceptsevents.htm" title="Within a cluster several types events, actions, and services can occur.">Cluster events</a><img src="./deltaend.gif" alt="End of change" /></div>
|
|
</div>
|
|
<div class="relconcepts"><strong>Related concepts</strong><br />
|
|
<div><a href="rzaigmanage.htm" title="This topic contains information that covers some of the tasks that involve managing your clusters.">Manage clusters</a></div>
|
|
<div><a href="rzaigmanageclusterperformance.htm" title="When changes are made to a cluster, the overhead necessary to manage the cluster can be affected.">Cluster performance</a></div>
|
|
</div>
|
|
<div class="reltasks"><strong>Related tasks</strong><br />
|
|
<div><a href="rzaigmanagemonitor.htm" title="Taking appropriate actions when necessary, the cluster resource services performs basic monitoring of a cluster and its components using the reliable message function and heartbeat monitoring.">Monitor cluster status</a></div>
|
|
</div>
|
|
</div>
|
|
</body>
|
|
</html> |