Patent ID: 6915389

Claim:
A storage system comprising, a plurality of disk control clusters, each of said plurality of disk control clusters having one or a plurality of channel interface units having interfaces with host computers, one or a plurality of disk interface units having interfaces with disk drives, and a local shared memory unit for storing data to be read/written from/to said disk drives, control information about transfer of said data and management information about said disk drives, said channel interface units executing data transfer between the interfaces with said host computers and said local shared memory units in response to a read/write request from said host computers, said disk interface units executing data transfer between said disk drives and said local shared memory units to read/write the data; a global information control unit for storing the data to be read/written from/to said disk drives and the management information about said disk control clusters; an interconnection connected between said plurality of disk control clusters; and a switch for connecting the channel interface units in said plurality of disk control clusters, wherein said switch has a memory to which the management information stored in said global information control unit is copied.