Adaptec DuraStor 7220SS User Manual page 142

Stripe set (RAID 0)—An arr ay made up of two or more drives. The
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stripe set distributes, or stripes, data evenly across the partitions in
equal-sized sections called chunks.
Mirror set (RAID 1)—An array made up of two drives. A mirror
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set stores and maintains the same, or redundant, data in each of
its two partitions.
RAID 3 set—An array made up of three or more disk drives. It
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uses parallel access, meaning that normally all member disk
drives participate concurrently in every I/O operation directed at
the array. Each virtual disk I/O operation is subdivided and
striped or distributed across all data disks; therefore, it uses small
stripe depth compared to I/O size. Parity data is stored on a
separate parity disk drive.
RAID 4 set—An array made up of three or more disk drives. Data
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blocks are distributed as with a stripe set (RAID 0). It differs from
RAID 3 in two ways: (1) it uses independent access (rather than
parallel access), meaning the arrays' disk drives may operate
independently of each other allowing multiple simultaneous
operations, and (2) stripe depth is large compared to I/O size.
Parity data is stored on a separate parity disk drive.
RAID 5 set—An array that is similar to a stripe set, except that it
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uses parity to provide redundancy. A RAID 5 set must be made
up of at least three equal-sized partitions. One chunk is used for
parity data for each set of chunks striped across the partitions.
The parity chunks are distributed across all drives containing
partitions of the RAID 5 set.
Stripe set of mirror sets (RAID 0/1)—An array made up of two or
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more equal-sized mirror sets that also st ripes the data across all
drives.
Stripe set of RAID 5 sets (RAID 0/5)—An array made up of two
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or more equal-sized RAID 5 sets that also stripes the data across
all drives.
For more detailed descriptions of each array type, see Appendix A,
General Storage Concepts.
Choosing Your Array Type
B-3