Patent ID: 8090923

Claim:
A storage system in which first and second storage control devices are connected to each other for communications, the system comprising: a first volume that is provided virtually to the first storage control device; a second volume that is provided virtually to the second storage control device with correspondence in terms of a storage space with the first volume, and is accessed in response to an access request to the first volume; a pool section that keeps a plurality of physical storage areas for allocation to the second volume in response to a write access request to the second volume; a first control section that is provided to the first storage control device, issues a command to the second volume in response to the access request to the first volume, and performs data reading/writing from/to the second volume; and a second control section that is provided to the second storage control device, performs data input/output to/from the second volume in response to the command from the first control section, and allocates, to the second volume, in response to a write access request from the first control section, any of the plurality of physical storage areas in the pool section not yet in use, wherein when receiving a first predetermined command about the first volume, the first control section converts, for transmission to the second control section, the first predetermined command into a second predetermined command to relatively reduce a write access frequency to the second volume.