REDUNDANT DISK STORAGE DEVICE

摘要

PROBLEM TO BE SOLVED: To effectively use a spare disk drive without exchanging or scrapping by restoring data without regard to the capacity of a disk drive constituting RAID and that of the spare disk drive in a disk storage device having a RAID function and restoring data by the spare disk drive when a fault occurs in the disk drive. SOLUTION: By referring to a whole disk drive resource information table and a spare disk drive resource information table, when a fault occurs in the disk drive constituting RAID, data is divided and restored by a plurality of spare disk drives of a capacity smaller than that of the disk drive where the fault occurs. When the fault of RAID occurs in data in the plurality of disk drives, the data is restored by a single spare disk drive.