5 creating raid arrays, Creating raid arrays, Section 8.5, “creating raid arrays – Avago Technologies LSI SAS 3041E-R User Manual

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Creating RAID Arrays

8-13

Version 1.3

Copyright © 2001, 2002, 2007 by LSI Logic Corporation. All rights reserved.

8.5

Creating RAID Arrays

This section explains how to use the Setup utility to create RAID arrays.
The first subsection explains how to create mirrored (IM and RAID 1E)
arrays. The second subsection explains how to create striped (IS) arrays.
Here are brief descriptions of the different types of arrays:

Integrated Mirroring (IM) arrays are simple sector-to-sector physical
mirrors of one drive to another drive. Two disk drives are used for IM
arrays. An optional hot spare disk can also be added.

RAID 1E arrays use a striped layout in which each stripe unit has a
secondary copy stored on a different disk. Three to six disk drives
are used for this type of array. (The maximum is five disk drives if a
hot spare disk is also defined.)

Integrated Striping (IS) arrays write data across multiple disks
instead of onto one disk. This is accomplished by partitioning each
disk’s storage space into stripes. The stripes are interleaved round-
robin across all disks in the array, so that the combined storage
space is composed alternately of stripes from each disk. As a result,
data can be retrieved faster.

The version of the BIOS determines which kind of arrays you can create
on the host adapter: some BIOS versions support only mirrored arrays,
while others support only striped arrays.

Incompatbl

Device is not compatible for use as part of a RAID Array

Too Small

Disk is too small to mirror existing data

Max # Dsks

Maximum # of disks allowed for this type of array has been
reached

Not Valid

Disk does not support SMART and cannot be used in a RAID
array

Qtag/Dis

Device has Qtags or Disconnects Disabled

Table 8.6

Status Field Definitions (Cont.)

Status

Definition

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