Raid 0 (Striping); Raid 1 (Mirrored); Raid 5 (Parity); Raid 6 (Dual Parity) - Silicon Graphics InfiniteStorage Server 3500 User Manual

RAID 0 (Striping)

RAID 1 (Mirrored)

RAID 5 (Parity)

RAID 6 (Dual Parity)

RAID 10 (Mirrored Stripes)

RAID 50 (Striping with Parity)

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Disk striping allows the writing of data across multiple physical disks instead of just one physical
disk. It involves partitioning each disk drive storage space into stripes that can vary in size from
8KB to 128KB.
Disk mirroring has two disks; data is written simultaneously to both disks. If one disk fails, the
contents of the disk can be used to run the system and reconstruct the failed disk.
RAID 5 stripes both data and parity information across three or more drives. Fault tolerance is
maintained by ensuring that the parity information for any given block of data is placed on a drive
separate from those used to store the data itself. The performance of a RAID 5 array can be
"adjusted" by trying different stripe sizes until one is found that is well-matched to the application
being used.
Striped set with dual distributed parity. Provides fault tolerance from two drive failures; the array
continues to operate with up to two failed drives. With dual parity, it gives time to rebuild the array
without the data being volatile while the failed drive is being recovered.
RAID 10 is a combination of RAID 1 and RAID 0. RAID 10 is a stripe across a number of
mirrored sets. It combines the best features of striping and mirroring to yield large arrays with high
performance in most uses and superior fault tolerance.
RAID 50 employs RAID 0 striping across lower-level RAID 5 arrays. One disk in each sub-array
can fail without a loss of data.
Disk RAID Support
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