Patent ID: 8171248
Filing Date: 2012-05-01
Classification: G06F

Abstract:
1. A method of controlling a storage system having a first switch device, a second switch device and at least one storage device connected to the first and second switch devices, the storage device having first and second storage areas, each of the first switch device and the second switch device being capable of controlling access to the first storage area and the second storage area of the storage device, the first switch device and the second switch device have updatability information including updatability of status information, and the second switch device changes the updatability information to a state describing that an update of the status information is uppermitted after the access is executed, the method comprising: receiving a request for copying data stored in the first storage area to the second storage area from a host; transmitting notification of initiation of copying for copying data stored in the first storage area to the second storage area from the first switch device to the second switch device; executing the copying by the first switch device; controlling the second switch to refer to status information indicative of progress of the copying upon receiving a request for access to the first or second storage area by the host before completion of the copying; determining whether to permit access to the first or second storage area by the second switch device on the basis of the status information; determining whether the access requires the update of the status information by the second switch device; transmitting the request for accessing from the second switch device to the first switch device when the access requires the update of the status information; transmitting a request for obtaining the updatability information from the second switch device to the first switch device upon accessing; executing the copying by the first switch device intermittently; changing the updatability information to the state describing that the status information is not updatable by the first switch device; and transmitting information permitting the update of the status information from the first switch device to the second switch device.