DISK SUBSYSTEM, INSPECTION DIAGNOSING METHOD FOR DISK SUBSYSTEM AND DATA RESTORING METHOD FOR DISK SUBSYSTEM

摘要

PROBLEM TO BE SOLVED: To obtain a highly reliable disk subsystem by preventing the system down of a disk subsystem constituting a RAID(redundant array of inexpensive disks). SOLUTION: This subsystem composing a RAID of a preliminary magnetic disk drive and plural magnetic disk drives 119 to 122 is provided with an inspection diagnosing means which performs inspection diagnosis of the preliminarily magnetic disk drive at preset timing. It is also provided with an alternate processing means which performs alternate processing of the recording place of data where a fault is detected when the fault is detected in the drives 119 to 122 by the inspection diagnosing means.