Device parity protection with hot spare disk units concepts

 

Device parity protection hot spare disk units are spare disk units stored on a system to replace failed disks in case a disk failure occurs.

A hot spare disk unit is stored on the system as a non-configured disk. When a disk failure occurs, the system exchanges the hot spare disk unit with the failed disk unit. Both of the disk units must be the same capacity for a Small Computer System Interface (SCSI) IOA, or the same or larger capacity for a Serial Attached SCSI (SAS) IOA, and under the same IOA in order for the exchange to occur. After the exchange occurs, the system rebuilds the data on the new disk unit.

There are two ways to include the hot spare disk units in your system:

  1. You can configure the hot spare disk unit when you initially start device parity protection. Starting device parity protection with hot spare protection explains how to include hot spare disk units when starting device parity protection. When selecting this option, the system automatically determines if one or two hot spares should be created and which available disk units are selected based on the total number and capacity of disk units attached to the IOA.

    When you start device parity protection with hot spare disk units, the new hot spare disk units are not committed to any particular parity set. The hot spare disk unit protects the first failed disk unit that has parity protection, is the appropriate capacity for the hot spare, and is under the same IOA as the hot spare.

  2. You can create a hot spare disk unit from non-configured disk units on your system. Starting hot spare protection explains how to include hot spare disk units to your system. When selecting this option, you should determine if one or two hot spares are desired and which available units will become hot spares based on the total number of disk units attached to the IOA and their capacity.

 

Parent topic:

Using hot spare device parity protection