INTRODUCTION
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speed data throughput. RAID 0 breaks up data into smaller blocks
and then writes a block to each drive in the array. Disk strip-
ing enhances performance because multiple drives are accessed
simultaneously; the reliability of RAID Level 0 is less because the
entire array will fail if any one disk drive fails, due to a lack of
redundancy.
1.7.2 RAID 1
RAID 1 is also known as “disk mirroring”; data written to one disk
drive is simultaneously written to another disk drive. Read per-
formance may be enhanced if the array controller can, in parallel,
accesses both members of a mirrored pair. During writes, there
will be a minor performance penalty when compared to writing
to a single disk. If one drive fails, all data (and software applica-
tions) are preserved on the other drive. RAID 1 offers extremely
high data reliability, but at the cost of doubling the required data
storage capacity.
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