Patent ID: 8433949

Claim:
A disk array apparatus, comprising: a plurality of physical disks; at least one spare disk; a managing unit for managing a usage condition of a plurality of block areas formed by dividing respective storage areas of the physical disks and the spare disk; a unit for determining, when a fault occurs in a physical disk of the plurality of physical disks and having a plurality of block areas, whether the block areas of the physical disk are used areas or unused areas on the basis of the usage condition; a unit for recovering data in relation to the block areas determined to be the used areas and writing the recovered data to a plurality of the block areas of the spare disk corresponding to the used areas; a unit for setting that the physical disk is usable when data recovery is completed in relation to all of the block areas determined to be the used areas; and a unit for writing zero data to the block areas of the spare disk corresponding to the block areas determined to be the unused areas after setting an indication that the physical disk can be used.