Patent ID: 9256372
Filing Date: 2016-02-09
CPC Classification: G06F

Claim Text:
1. A storage device comprising: a storage unit that stores a primary volume storing data accessed by a first external device and a secondary volume storing data accessed by a second external device; and a controller that controls access to the primary volume and the secondary volume, wherein the controller copies the data stored in the primary volume, stores the copied data in the secondary volume, then creates a memory region storing first mount information necessary for the second external device to mount the second volume, associates a snapshot thereof with an identifier of the snapshot, and saves the snapshot and the identifier, when a request designating the identifier of the snapshot for access to the secondary volume is received from the second external device, the controller generates a virtual volume which can be mounted by the second external device, by using the snapshot corresponding to the designated identifier of the snapshot and using the data stored in the secondary volume, and the controller presents the generated virtual volume to the second external device as a reply to the request.