Patent ID: 7716434

Claim:
A storage system comprising: a first network storage device including a primary volume and a first interface (I/F); a second network storage device including a secondary volume that forms a mirror pair with said primary volume, said second network storage device including a second I/F; and a virtualization apparatus that is connected to be able to communicate with said first network storage device via said first interface and said second network storage device via said second interface, and that allows a client connected via a network to access the first and second network storage devices as one virtual network storage system; wherein a computer is connectable to access the secondary volume which forms the mirror pair with the primary volume in the second network storage device, separately from said virtualization apparatus via a third I/F included in the second network storage device; and wherein access control of said secondary volume is configured by: creating the mirror pair between said primary volume and said secondary volume at a certain point in time by taking a complete initial copy of said primary volume and storing said complete initial copy in said secondary volume, receiving in said second storage device a suspend request, placing the mirror pair into a suspend status to permit setting of the access control according to user selection, if the user chooses a read only mode, setting said secondary volume to the read only mode for input/output (I/O) requests from said computer and re-synchronizing the mirror pair, and if the user chooses a read/write mode, setting said secondary volume to the read/write mode for I/O requests from said computer and re-synchronizing the mirror pair.