HP ProLiant DL580 G2, Руководство пользователя

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• Analyze current corporate and departmental structure.
• Analyze the current fi le server structure and environment.
• Plan properly to ensure the best con fi guration and use of storage.
• Determine the desired priority of fault tolerance, performance,
and storage capacity.
• Use the determined priority of system characteristics to
determine the optimal striping policy and RAID level.
• Include the appropriate number of physical drives in the arrays to
create logical storage elements of desired sizes.
Arrays
With an array controller installed in the system, the capacity of several
physical drives can be logically combined into one or more logical
units called arrays. When this is done, the read/write heads of all the
constituent physical drives are active simultaneously, dramatically reducing
the overall time required for data transfer.
NOTE:
Depending on the storage server model, array con fi guration may not
be possible or necessary.
L1
P1 P2 P3
Figure 4 Con fi guring the physical drives into an array
dramatically improves read/write ef fi ciency
Because the read/write heads are active simultaneously, the same amount
of data is written to each drive during any given time interval. Each unit of
data is termed a block. The blocks form a set of data stripes over all the
hard drives in an array, as shown in Figure 5 .
HP ProLiant Storage Server user guide 33