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