59 lines
3.5 KiB
HTML
59 lines
3.5 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="Decide which disk pools to protect" />
|
||
|
|
<meta name="DC.Relation" scheme="URI" content="rzalymirrorplan.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="hdrmirror1" />
|
||
|
|
<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>Decide which disk pools to protect</title>
|
||
|
|
</head>
|
||
|
|
<body id="hdrmirror1"><a name="hdrmirror1"><!-- --></a>
|
||
|
|
<!-- Java sync-link --><script language="Javascript" src="../rzahg/synch.js" type="text/javascript"></script>
|
||
|
|
<h1 class="topictitle1">Decide which disk pools to protect</h1>
|
||
|
|
<div><p>Mirrored protection is configured by disk pool because it is the user's
|
||
|
|
level of control over single-level storage. Mirrored protection can be used
|
||
|
|
to protect one, some, or all disk pools on a system. However, multiple disk
|
||
|
|
pools are not required to use mirrored protection. Mirrored protection works
|
||
|
|
well if all disk units on a system are configured into a single disk pool
|
||
|
|
(the default on the iSeries™ server). In fact, mirroring reduces the need
|
||
|
|
to partition auxiliary storage into disk pools for data protection and recovery.
|
||
|
|
However, disk pools might still be desirable for performance and other reasons.</p>
|
||
|
|
<p>To provide the best protection and availability for the entire system,
|
||
|
|
all disk pools in the system should have mirrored protection: </p>
|
||
|
|
<ul><li>If the system has a mixture of some disk pools with and some disk pools
|
||
|
|
without mirrored protection, a disk unit failure in a disk pool without mirrored
|
||
|
|
protection severely limits the operation of the entire system. Data can be
|
||
|
|
lost in the disk pool in which the failure occurred. A long recovery might
|
||
|
|
be required.</li>
|
||
|
|
<li>If a disk fails in a mirrored disk pool, and the system also contains
|
||
|
|
disk pools that are not mirrored, data is not lost. However, in some cases, <a href="rzalycmaintdef.htm">Concurrent maintenance</a> might not be possible.</li>
|
||
|
|
</ul>
|
||
|
|
<p>The disk units that are used in disk pools should be selected carefully.
|
||
|
|
For best protection and performance, a disk pool should contain disk units
|
||
|
|
that are attached to several different I/O processors. The number of disk
|
||
|
|
units in the disk pool that are attached to each I/O processor should be the
|
||
|
|
same (that is, balanced).</p>
|
||
|
|
</div>
|
||
|
|
<div>
|
||
|
|
<div class="familylinks">
|
||
|
|
<div class="parentlink"><strong>Parent topic:</strong> <a href="rzalymirrorplan.htm">Plan for mirrored protection</a></div>
|
||
|
|
</div>
|
||
|
|
</div>
|
||
|
|
</body>
|
||
|
|
</html>
|