Managing Spares; Managing Dynamic Spares - HP 2000fc Reference Manual

Managing Spares

Controllers in your system automatically reconstruct redundant (fault-tolerant)
virtual disks (RAID 1, 3, 5, 6, 10, and 50) if a virtual disk becomes critical and a
properly sized spare disk is available. A virtual disk becomes critical when one or
more of its disks fails.
There are three types of spares:
A vdisk spare is an available drive that is assigned to a specific virtual disk.
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A global spare is an available drive that can act as a spare for any failed drive in
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any redundant virtual disk. Global spares are available to any redundant virtual
disk in the system. If a drive in a virtual disk fails, the controller can use a global
spare to reconstruct the critical virtual disk.
A dynamic spare is a properly sized available drive that is automatically assigned
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by the system.
When a disk fails, the system looks for a vdisk spare first. If it does not find a
properly sized vdisk spare, it looks for a global spare. If it does not find a properly
sized global spare and the dynamic spares option is enabled, it takes any properly
sized available drive. If no properly sized spares are available, reconstruction must
be started manually.
For more information, see "Managing Dynamic Spares" on page 80, "Managing
Vdisk Spares" on page 81, "Managing Global Spares" on page 83, or the topic about
reconstructing a virtual disk in "Troubleshooting Using SMU" on page 195.

Managing Dynamic Spares

The dynamic spares feature lets you use all of your disk drives in redundant virtual
disks without designating one as a spare. With dynamic spares enabled, if a drive
fails and you replace it with a properly sized drive, the storage system rescans the
bus, finds the new drive, automatically designates it a spare, and starts
reconstructing the virtual disk. A properly sized drive is one whose capacity is equal
to or greater than the smallest drive in the virtual disk.
If a vdisk spare, global spare, or properly sized available drive is already present,
the dynamic spares feature uses that drive to start the reconstruction and the
replacement drive can be used for another purpose.
80 HP StorageWorks 2000 Family Modular Smart Array reference guide • August 2008