User's Manual

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.

Related Links

Dedicated Hot Spare Considerations

Dedicated 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.

Hot spare implementation varies for each controller controller. For more information on hot spares, see:

• Considerations For Hot Spares On PERC S100 And PERC S300 Controllers

• Global Hot Spare Considerations On A SAS 6/iR

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.