IBM SSA 32H3816 User Manual

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C.2 RAID Functions

Redundant Array of Independent Disks (RAID) technology gives you:

Larger disk capacit

Immediate availability and, depending on the RAID level, recovery of dat
Redundancy of data at a level that you can choose

RAID technology stores data across groups of disk drives that are known as disk arrays. Subject to the level of RAID that you are

using, this method of data storage provides the data redundancy that is needed for a secure system, and can allow faster retrieval
of data through multiple channel access. Also, if a disk drive fails, you can normally exchange that disk drive without interruption of
normal system operation.

The disk arrays can provide data redundancy that ensures that no data is lost if one disk drive in the array fails. The method that is

used to write data to an array is related to the level of RAID that you are using. Disk arrays are contained in array subsystems. You
can configure your subsystem with one or more arrays.

The SSA RAID Adapter provides RAID-0, RAID-1, and RAID-5 facilities and access to individual SSA disk drives that are not

configured as members of an array.

Subtopics

C.2.1 RAID-0

C.2.2 RAID-1

C.2.3 RAID-5

C.2.4 Hot Spares

C.2.5 Disk Array States

SSA RAID Adapter Installation and User's Guide.

RAID Functions

C.2 - 1