User's Manual

Protecting Your Virtual Disk with a Hot Spare 247
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Protecting Your Virtual Disk with a
Hot Spare
When you create a redundant virtual disk using a RAID controller, you have
the opportunity to maintain system operations even when a disk fails. To do
so, you would assign a hot spare to the virtual disk. When a disk fails, the
redundant data is rebuilt onto the hot spare without interrupting system
operations.
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 is different for different controllers. For more
information.
• Considerations for Hot Spares on S100, and S300 Controllers
• Global Hot Spare Considerations on a SAS 6/iR
The following sections describe procedures for assigning a hot spare:
• Assign and Unassign Global Hot Spare
• Assign and Unassign Dedicated Hot Spare
Setting Hot Spare Protection Policy
The Hot Spare Protection Policy is supported only on Serial Attached SCSI
(SAS) controllers.