Raid 6 – Block And Double Parity Stripe - Promise Technology VTRAK E610f Product Manual

VTrak E-Class Product Manual
RAID 6 – Block and Double Parity Stripe
RAID level 6 stores dual parity data is rotated across the physical drives along
with the block data. A RAID 6 disk array can continue to accept I/O requests
when any two physical drives fail.
Data
Blocks
The total capacity of a RAID 6 disk array is the smallest physical drive times the
number of physical drives, minus two.
Hence, a RAID 6 disk array with six 100 GB hard drives will have a capacity of
400 GB. A disk logical drive with four100 GB hard drives will have a capacity of
200 GB.
RAID 6 becomes more capacity efficient in terms of physical drives as the
number of physical drives increases.
RAID 6 offers double fault tolerance. Your logical drive remains available when
up to two physical drives fail.
RAID 6 is generally considered to be the safest RAID level, except for RAID 60.
RAID 6 requires a minimum of four physical drives and a maximum of 16.
Recommended applications: Accounting, financial, and database servers; any
application requiring very high availability.
Double Distributed (Wide-space Q+Q) Parity
physical drives
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