Users Guide
Protecting Your Virtual Disk With A Hot Spare
When you create a virtual disk using a RAID controller, it enables the system to continue functioning even during a disk failure. This feature
can be enabled by assigning a hot spare to the virtual disk. When a disk fails, the redundant data is rebuilt onto the hot spare without
interrupting system operations.
Topics:
• Understanding Hot Spares
• Setting Hot Spare Protection Policy
Understanding Hot Spares
A hot spare is an unused backup physical disk that can be used to rebuild data from a redundant virtual disk. Hot spares remain in standby
mode. When a physical disk that is used in a redundant virtual disk fails, the assigned hot spare is activated to replace the failed physical
disk without interrupting the system or requiring your intervention. If a virtual disk using the failed physical disk is not redundant, then the
data is permanently lost without any method (unless you have a backup) to restore the data.
The following sections describe procedures for assigning a hot spare:
• Assigning And Unassigning Global Hot Spare
• Assigning And Unassigning Dedicated Hot Spare
Setting Hot Spare Protection Policy
The Hot Spare Protection Policy is supported only on Serial Attached SCSI (SAS) controllers.
The Hot Spare Protection Policy provides you with a higher protection level for the virtual disks by enabling you to specify the number of
dedicated/global hot spares to be assigned to the virtual disks/controller. You can also specify the severity levels for the protection policy.
Storage Management sends alerts when the hot spare protection policy is violated.
Storage Management does not provide a default policy; however, you can determine the hot spare protection policy best suited for your
environment.
Dedicated Hot Spare Protection Policy
Table 28. Hot Spare Properties
Property Denition
RAID Level Indicates the RAID level(s) for which you want to congure the hot
spare protection policy.
Minimum Number of Disks Indicates the minimum number of physical disks to be assigned as
dedicated hot spares for the selected RAID level(s).
Severity Level Displays the severity level you want to assign to the generated
alert, if this policy is violated.
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