What is a hot spare drive?

Hot spares act as standby drives in RAID 1, RAID 5, or RAID 6 volume groups. They are fully functional drives that contain no data. If a drive fails in the volume group, the controller automatically reconstructs data from the failed drive to a hot spare.

If a drive fails in the storage array, the hot spare drive is automatically substituted for the failed drive without requiring a physical swap. If the hot spare drive is available when a drive fails, the controller uses redundancy data to reconstruct the data from the failed drive to the hot spare drive.

A hot spare drive is not dedicated to a specific volume group. Instead, you can use a hot spare drive for any failed drive in the storage array with the same capacity or smaller capacity. A hot spare drive must be of the same media type (HDD or SSD) as the drives that it is protecting.

Note: Hot spare drives are not supported with pools. Instead of hot spare drives, pools use the preservation capacity within each drive that comprises the pool.