INTRODUCTION
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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