HP ProLiant DL580 G2, Руководство пользователя

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S1
S2
S3
S4
B1
B4
B7
B2
B5
B8
B11 B10 B12
B6
B3
B9
Figure 5 RAID 0 (data striping) (S1-S4) of data blocks (B1-B12)
For data in the array to be readable, the data block sequence within
each stripe must be the same. This sequencing process is performed by
the array controller, which sends the data blocks to the drive write heads
in the correct order.
A natural consequence of the striping process is that each hard drive in a
given array contains the same number of data blocks.
NOTE:
If one hard drive has a larger capacity than other hard drives in the same
array, the extra capacity is wasted because it cannot be used by the array.
Fault tolerance
Drive failure, although rare, is potentially catastrophic. For example, in
Figure 5 using simple striping, failure of any hard drive leads to failure of
all logical drives in the same array, and hence to data loss.
To protect against data loss from hard drive failure, storage servers should
be con fi gured with fault tolerance. HP recommends adhering to RAID 5
con fi gurations.
The table below summarizes the important features of the different kinds
of RAID supported by the Smart Array controllers. The decision chart in
34 Storage Management Overview