66 lines
4.0 KiB
HTML
66 lines
4.0 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="topic" />
|
||
|
|
<meta name="DC.Title" content="Concurrent maintenance" />
|
||
|
|
<meta name="DC.Relation" scheme="URI" content="rzalymirrorwork.htm" />
|
||
|
|
<meta name="copyright" content="(C) Copyright IBM Corporation 2002, 2006" />
|
||
|
|
<meta name="DC.Rights.Owner" content="(C) Copyright IBM Corporation 2002, 2006" />
|
||
|
|
<meta name="DC.Format" content="XHTML" />
|
||
|
|
<meta name="DC.Identifier" content="hdrcmaintdef" />
|
||
|
|
<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>Concurrent maintenance</title>
|
||
|
|
</head>
|
||
|
|
<body id="hdrcmaintdef"><a name="hdrcmaintdef"><!-- --></a>
|
||
|
|
<!-- Java sync-link --><script language="Javascript" src="../rzahg/synch.js" type="text/javascript"></script>
|
||
|
|
<h1 class="topictitle1">Concurrent maintenance</h1>
|
||
|
|
<div><p>Concurrent maintenance is the process of repairing or replacing a failed
|
||
|
|
disk-related hardware component while the system is being used for normal
|
||
|
|
operations.</p>
|
||
|
|
<p>On systems without mirrored protection or device parity protection, the
|
||
|
|
system is not available when a disk-related hardware failure occurs and remains
|
||
|
|
unavailable until the failed hardware is repaired or replaced. However, with
|
||
|
|
mirrored protection the failing hardware can often be repaired or replaced
|
||
|
|
while the system is being used.</p>
|
||
|
|
<p>Concurrent maintenance support is a function of system unit hardware packaging.
|
||
|
|
Mirrored protection only provides concurrent maintenance when the hardware
|
||
|
|
and packaging of the system support it. The best hardware configuration for
|
||
|
|
mirrored protection also provides for the maximum amount of concurrent maintenance.</p>
|
||
|
|
<p>It is possible for the system to operate successfully through many failures
|
||
|
|
and repair actions. For example, a failure of a disk head assembly does not
|
||
|
|
prevent the system from operating. A replacement of the head assembly and
|
||
|
|
synchronization of the mirrored unit can occur while the system continues
|
||
|
|
to run. The greater your level of protection, the more often concurrent maintenance
|
||
|
|
can be performed.</p>
|
||
|
|
<p>On some models, the system restricts the level of protection for unit 1
|
||
|
|
and its mirrored unit to only IOA-level protection. See "Mirrored Protection
|
||
|
|
- Configuration Rules" in <a href="../books/sc415304.pdf" target="_blank">Backup
|
||
|
|
and Recovery</a> <img src="wbpdf.gif" alt="Link to PDF" /> for more information.</p>
|
||
|
|
<p>Under some conditions, diagnosis and repair can require active mirrored
|
||
|
|
units to be suspended. You may prefer to turn off the system to minimize
|
||
|
|
the exposure of operating with less mirrored protection. Some repair actions
|
||
|
|
require that the system be powered down. Deferred maintenance is the process
|
||
|
|
of waiting to repair or replace a failed disk-related hardware component until
|
||
|
|
the system can be powered down. The system is available, although mirrored
|
||
|
|
protection is reduced by whatever hardware components have failed. Deferred
|
||
|
|
maintenance is only possible with mirrored protection or device parity protection.</p>
|
||
|
|
</div>
|
||
|
|
<div>
|
||
|
|
<div class="familylinks">
|
||
|
|
<div class="parentlink"><strong>Parent topic:</strong> <a href="rzalymirrorwork.htm">How mirrored protection works</a></div>
|
||
|
|
</div>
|
||
|
|
</div>
|
||
|
|
</body>
|
||
|
|
</html>
|