Patent ID: 7249220

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