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<title>Example: Logical device configurations</title>

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<h1>Example: Logical device configurations</h1>
<h2>Example 1 </h2>
<p>The pool consists of three 1 <a href="ggb.htm">GB</a> drives. You assign <a href="craid0.htm">RAID
  level-0</a>, which uses all the physical drives in the pool with no redundant
  or parity storage; then, you type 1000. The logical device will actually only
  use 999 <a href="gmb.htm">MB</a> because it is the number closest to and lower
  than 1000 that is divisible by 3. </p>
<h2>Example 2 </h2>
<p>The pool consists of three 1 GB drives. You assign <a href="craid1e.htm">RAID
  level-1E</a>, which provides disk mirroring and stripes data across all physical
  drives in the pool. Because the data is mirrored, the capacity of the logical
  drive is 50% of the physical capacity of the physical drives grouped in the
  pool. If you type 1000, the physical capacity used is 2000 MB, twice that of
  the logical device size. The number that is closest to and lower than 2000 that
  is divisible by 3 is 1998, which will be the actual space used. The logical
  drive size is 999 MB, which is 50% of the physical capacity. </p>
<h2>Example 3</h2>
<p>The pool consists of three 1 GB drives and you assign <a href="craid5.htm">RAID
  level-5</a> . Data is striped across all three physical drives in the pool,
  but the space equivalent to that of one physical drive is used for redundant
  storage. Therefore, if you type 1000, the number 1000 remains in the Size (MB)
  field because it is divisible by 2 (drives), which is the space available for
  data. The physical capacity used is 1500 MB.</p>
<h2>More information</h2>
<ul>
  <li><a href="ccreld.htm">Understanding creating logical devices</a></li>
  <li><a href="cldsize.htm">Selecting the logical device size</a></li>
  <li><a href="craidlvl.htm">Selecting the RAID level by pool capacity</a></li>
  <li><a href="ccfgstep.htm">Configuring RAID and creating pools (action)</a></li>
  <li><a href="wwizpacc.htm">Creating logical devices in the wizard</a></li>
  <li><a href="cusable.htm">Example: Usable and unusable capacity</a></li>
</ul>

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