IBM ServeRAID, User Reference

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Understanding RAID level-x0
Note: RAID level-x0 is available only on the ServeRAID-4 and ServeRAID-5i
controllers.
RAID level-x0 refers to RAID level-00, level-10, level-1E0, and level-50. RAID
level-x0 uses an array of arrays, or a
spanned array . The operating system uses
the spanned array logical drive in the same way as a regular array logical drive.
RAID level-x0 allows more physical drives in an array. The benefits of doing so are
larger logical drives, increased performance, and increased reliability. RAID level-0,
level-1E, level-5, and level-5E cannot use more than 16 physical drives in an array;
however, RAID level-1E0 and level-50 support 60 drives.
RAID level-x0 requires a minimum of two drives and supports a maximum of 60
drives.
The following illustration is an example of a RAID level-10 logical drive.
Start with six physical drives.
Create three arrays (labeled
A, B, and C), each array
using two physical drives.
A A
B C
A
Then create a spanned array
(labeled as *) that spans the
three arrays.
A A B C A
*
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IBM ServeRAID: User’s Reference, Version 5.10