Patent ID: 8843713

Claim:
A storage system, comprising: a master storage device and a secondary storage device in a first group; and a storage device in a second group; each of the master storage device and the secondary storage device in the first group including: a first storage unit capable of reservation of a storage area; and a first control unit to control the first storage unit, the first control unit in the master storage device being configured to operate as: a primary-side reserving unit to reserve a primary-side storage area in the first storage unit; a request unit to request the storage device in the second group to reserve a secondary-side storage area serving as copy destination area of the primary-side storage area; a checking unit to receive identifying information of the secondary-side storage area reserved by the storage device in the second group; a management storage unit to store the identifying information of the secondary-side storage area in the way of being associated with the primary-side storage area; and a transfer unit to transfer data stored in the primary-side storage area to the secondary-side storage area; the storage device in the second group including: a second storage unit capable of reservation of a storage area; and a second control unit to control the second storage unit, the second control unit being configured to operate as: a request accepting unit to accept a request for reserving the secondary-side storage area serving as the copy destination area of the primary-side storage area from the master storage device in the first group; a secondary-side reserving unit to reserve the secondary-side storage area in the second storage unit in response to the request; and a report unit to report identifying information of the reserved secondary-side storage area to the master storage device in the first group, wherein the first control unit of the master storage device in the first group manages information related to free area of the first storage unit in the master storage device and information related to free area of the first storage unit in the secondary storage device, and the first control unit of the master storage device in the first group operates as a distribution unit to distribute, to the secondary storage device in the first group and to the storage device in the second group, the information related to the free area of the first storage unit in the master storage device and the information related to the free area of the first storage unit in the secondary storage device.