Raid 1 - Areca ARC-1880 Series User Manual

APPENDIX

RAID 1

RAID 1 is also known as "disk mirroring"; data written on one
disk drive is simultaneously written to another disk drive. Read
performance will be enhanced if the array controller can, in
parallel, access 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
applications) 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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