Users Guide

l Data is replicated on the two disks.
l When a disk fails, the virtual disk still works. The data will be read from the failed disk's mirror.
l Better read performance, but slightly slower write performance.
l Redundancy for protection of data.
l RAID 1 is more expensive in terms of disk space since twice the number of disks are used than required to store the data without redundancy.
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Related Information:
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See the following:
l "Organizing Data Storage for Availability and Performance"
l "Comparing RAID Level and Concatenation Performance"
l "Controller-supported RAID Levels"
l "Number of Physical Disks per Virtual Disk"
l "Maximum Number of Virtual Disks per Controller"
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RAID Level 5 (Striping with distributed parity)
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RAID 5 provides data redundancy by using data striping in combination with parity information. Rather than dedicating a physical disk to parity, however, the
parity information is striped across all physical disks in the disk group.
Figure 3-4. Striping Disks with Distributed Parity
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RAID 5 Characteristics:
l Groups n disks as one large virtual disk with a capacity of (n-1) disks.
l Redundant information (parity) is alternately stored on all disks.
l When a disk fails, the virtual disk still works, but it is operating in a degraded state. The data is reconstructed from the surviving disks.
l Better read performance, but slower write performance.
l Redundancy for protection of data.

Related Information:

See the following:
l "Organizing Data Storage for Availability and Performance"
l "Comparing RAID Level and Concatenation Performance"
l "Controller-supported RAID Levels"