IBM 86655RY - Netfinity 7600 - 8665, Руководство по техническому обслуживанию аппаратной части

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Installing and configuring ServeRAID controllers
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With RAID level-1E, if one of the physical drives fails, the ServeRAID controller
switches read and write requests to the remaining functional drives in the RAID level-
1E array.
Understanding RAID level-5: RAID level-5 requires a minimum of three physical
drives. This RAID level stripes data and parity across all drives in the array. When
you assign RAID level-5 to an array, the capacity of the array is reduced by the
capacity of one drive (for data-parity storage).
RAID level-5 offers both data protection and increased throughput. RAID level-5
gives you higher capacity than RAID level-1, but RAID level-1 offers better
performance.
RAID level-5 requires a minimum of 3 drives and supports a maximum of 16 drives.
The following illustration is an example of a RAID level-5 logical drive.
Then, create a logical drive within that array.
The data is striped across the drives, creating blocks.
Notice that the stripe labeled
★
is the data stripe and the stripe labeled
★★
is
the copy of the preceding data stripe. Also notice that each block on the mirror
stripe is shifted one drive.
Start with four physical drives.
1 2 3
3 1 2
4 5 6
6 4 5
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