Patent ID: 7392336

Claim:
A switch device comprising: a host network interface to be coupled to host computers via a network; a storage network interface to be coupled to a first storage system which controls based on a first protocol and which has a first data volume storing data from a host computer and a second storage system which controls based on a second protocol and which has a second data volume storing data from a host computer, said first storage system and said second storage system have different functions; a processor coupled to the host network interface and the storage network interface; and a memory coupled to the processor; and a plurality of first virtual volumes corresponding to at least one of the first data volumes and the second virtual volumes are corresponding to at least one of the second data volumes, the first virtual volume and the second virtual volume to be provided for at least one of the host computers, wherein when a virtual volume specified by the a virtual volume identifier in the instruction is the first virtual volume corresponding to the first data volume, the processor sends to the first storage system, through the storage network interface, a first control information related to the first data volume according to the first protocol for the first storage system for controlling a function of the first storage system, and wherein when a virtual volume specified by the virtual volume identifier in the instruction is the second virtual volume corresponding to the second data volume, the processor sends to the second storage system, through the storage network interface, second control information related to the second data volume according to the second protocol for the second storage system for controlling a function of the second storage system, wherein the control information is sent by an Application Program Interface (API), and wherein the memory holds information indicating a relationship between device type of said first and second storage systems and an API for control of a function which is able to be executed by either the first storage system or the second storage system.