Patent ID: 7206900

Claim:
A disk array comprising: a plurality of data reproduction groups each including a plurality of disk units; a group of spare disks, each spare disk serving as a spare for at least one disk unit of said data reproduction groups; a first control unit, to be coupled to a host unit, for controlling input and output between said host unit and a cache memory; and a second control unit, coupled to said disk units and said spare disks, for controlling input and output between said cache memory, said disk units and said spare disks, wherein said second control unit includes a plurality of loop control portions each being connected to a fiber channel loop connecting one of the disk units of one of said data reproduction groups, wherein data of a disk unit of one data reproduction group, connected to one fibre channel loop, can be recovered using data of another disk unit of said one data reproduction group, wherein said another disk unit is connected to another fiber channel loop, wherein a status of each fiber channel loop is monitored by said second control unit, wherein said one data reproduction group includes disk units connected to different fibre channel loops, and wherein said loop control portion performs copying of data from a disk unit of a data reproduction group into a spare disk, and performs processing of read/write operation.