Patent ID: 8117411

Claim:
A storage system comprising: a first storage device, configured to be installed in a first site, including a first adapter and a first cache memory and providing a primary logical volume in which data received from a host computer via the first adapter and the first cache memory is written; a second storage device, configured to be installed in a second site, including a second adapter and a second cache memory and providing a virtual logical volume, which has no structure for storing data received from the first storage system via the second adapter and the second cache memory; and a third storage device, configured to be installed in a third site, including a third adapter and a third cache memory and providing a secondary logical volume in which data received from the second storage system via the third adapter and the third cache memory is written, wherein data written in the primary logical volume of the first storage device are remote-copied to the secondary logical volume of the third storage device via the virtual logical volume of the second storage device, wherein, when the storage system stops the remote-copy between the second storage device and the third storage device, the first storage device does not transmit data to be remote-copied to the virtual logical volume of the second storage device, and each of the first storage device, the second storage device and the third storage device manages an address location of each of one or more data, each of the one or more data being held by the respective storage device as data to be remote-copied/written to the secondary logical volume of the third storage device, and wherein, when the storage system resumes the remote-copy from the primary logical volume of the first storage device to the secondary logical volume of the third storage device via the virtual logical volume of the second storage device, a plurality of the address locations managed by the first storage device, the second storage device, and the third storage device are aggregated, and data corresponding to each of the aggregated address locations is transmitted from the primary logical volume of the first storage device to the secondary logical volume of the third storage device via the virtual logical volume of the second storage device.