Nvidia nForce2 Ultra 400, User Manual

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S-ATA RAID Configuration
Page 5-2
RAID 0 (Striping)
RAID 0 reads and writes sectors of data interleaved between 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 64KB. RAID 0 does not support fault tolerance.
RAID 1 (Mirroring)
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.
JBOD (Spanning)
A spanning disk array is equal to the sum of the all drives when the drives used are
having different capacities. Spanning stores data onto a drive until it is full, then
proceeds to store files onto the next drive in the array. When any disk member
fails, the failure affects the entire array. JBOD is not really a RAID and does not
support fault tolerance.
Others
Other RAID derivatives are RAID 10 and RAID 5. These RAID levels require more
than 2 drives to operate, combining the benefits of RAID 0 and RAID 1.