The Introduction of RAID
A-3
User’s Manual
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RAID Level 1
Mirroring and Duplexing
RAID 1 provides 100% redundancy by
mirroring one drive to another one. In the
event of a disk drive failure, the array
controller will automatically switch the
read/write activity to another drive.
Each individual drive can execute
simultaneous read operations. Mirroring
thus doubles the read performance of a
single drive and leaves the write
performance unchanged.
RAID 1 is a good entry-level redundant
system, since only two drives are required.
However, the cost of RAID 1 is higher
because one drive has to be used to store
duplicate data.
RAID Level 0+1
Performance and Security
RAID 0+1, which uses Hamming error
correction codes, is intended for use with
drives which do not have built-in error
detection. Because the check method of
Hamming code is very complicated, and
more than one drive is required to store ECC
information, RAID 2 offers no significant
advantages over RAID 3.
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Summary of Contents for Hot Rod 100 Pro
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