Mirrored protection

Mirrored protection is beneficial if you have a multibus system or a system with a large single bus. A greater number of disk units provides more opportunity for failure and increased recovery time.

Mirrored protection is local to a single system and is distinct from cross-site mirroring. Mirrored protection works to prevent outage on the system by keeping a second copy of the data on a mirrored disk unit. If one disk unit fails, the system relies on the mirrored disk unit.

Hot spare protection can be used with mirrored protection. When an appropriate hot spare disk unit exists in the system and a mirrored disk unit is suspended because of a disk failure, the hot spare disk unit replaces the failed subunit.