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

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Hardware Maintenance Manual: Netfinity 7600 – Type 8665 Models 1RY, 2RY
Note: The ServeRAID Manager program Express configuration does not default to
RAID level-5E. If you have four physical drives, Express configuration
defaults to RAID level-5 with a hot-spare drive.
Understanding RAID level-x0: RAID level-x0 refers to RAID levels-00, 10, 1E0, and
50. RAID level-x0 includes more physical drives in an array. The benefits of doing so
are larger logical drives, increased performance, and increased reliability. RAID
levels-0, 1, 1E, 5, and 5E cannot use more than 16 physical drives in an array.
However, RAID levels-00, 10, 1E0, and 50 include more physical drives by managing
an array of arrays, or a spanned array. The operating system uses the spanned array
logical drive the same as a regular array logical drive.
The data is striped across the drives, creating blocks in the logical drive.
The storage of the data parity (denoted by
★
) is striped, and it shifts from drive to
drive as it does in RAID level-5.
Notice that the spare drive is not striped.
If a physical drive fails in the array, the data from the failed drive is compressed
into the distributed spare drive. The logical drive remains RAID level-5E.
When you replace the failed drive, the data for the logical drive decompresses and
returns to the original striping scheme.
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