RAID CONFIGURATION
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RAID 0 (Stripe)
RAID 0 reads and writes sectors of data interleaved among multiple drives. If any disk member
fails, it affects the entire array. The disk array data capacity is equal to the number of drive
members times the capacity of the smallest member. The striping block size can be set from
4KB to 128KB. RAID 0 does not support fault tolerance.
RAID 1 (Mirror)
RAID 1 writes duplicate data onto a pair of drives and reads both sets of data in parallel. If one
of the mirrored drives suffers a mechanical failure or does not respond, the remaining drive will
continue to function. Due to redundancy, the drive capacity of the array is the capacity of the
smallest drive. Under a RAID 1 setup, an extra drive called the “spare drive” can be attached.
Such a drive will be activated to replace a failed drive that is part of a mirrored array. Due to the
fault tolerance, if any RAID 1 drive fails, data access will not be affected as long as there are
other working drives in the array.
RAID 5 (Parity)
RAID 5 provides data striping at the byte level and also stripes error correction information. This
results in excellent performance and good fault tolerance. Level 5 is one of the most popular
implementations of RAID.
RAID 10 (0+1)
RAID 10 is a combination of striping and mirroring. This configuration provides optimal speed
and reliability, but you need four SATA hard disks.
Recovery
This level copies data between a master and a recovery disk, so the capacity of the array is
equal to the capacity of the smaller drive. It’s no need to set the strip size for Recovery, but you
must select a sync mode to update the volume.
Comparison Table :
Solution
Hard Disks No.
Capacity
Performance
Reliability
Application
RAID0
>=2
All
Highest
Dangerous
Look for speed
RAID1
2
50%
Read faster
Excellent
100% Data backup
RAID5
>=3
N-1
Read faster
Write slower
Good
Limited budget
RAID10
>=4
(Even number)
Smallest
*2
High
Excellent
Unlimited budget
Recovery
2
Smaller
Read faster
Excellent
100% Data backup
