5
66
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.
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
