Users Guide

Table Of Contents
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
Dedicated Hot Spare Considerations
Considerations For Hot Spares On PERC S100, PERC S300, PERC S130 and later controllers
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:
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 PERC 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 44. Hot Spare Properties
Property Definition
RAID Level Indicates the RAID level(s) for which you want to configure
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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