Patent ID: 7120739

Claim:
A storage system, comprising: plural protocol transformation units that each comprise an interface to one of an external equipment and a hard drive unit, and convert, into a protocol within the storage system, a protocol for read and write for data exchanged with the one of the external equipment and the hard drive unit; plural data caching control units each comprising a cache memory that stores data read from/written to the hard drive unit and a microprocessor that controls the cache memory; and a management information memory unit that stores management information on the storage system, wherein the plural protocol transformation units and the plural data caching control units are connected to each other through an interconnection; wherein the plural data caching control units are divided into plural control clusters each comprising at least two or more data caching control units; control of the cache memory is conducted independently for each of the plural control clusters; and one of the plural data caching control units having at least one processor and manages, as a single system, the plural protocol transformation units and the plural control clusters, by the processor in the one of the plural data caching control units, reading the management information stored in the management information memory unit.