Patent ID: 7120673
Filing Date: 2006-10-10
Classification: G06F

Abstract:
1. A storage server for providing a virtualized storage subsystem accessible by a plurality of hosts, the storage server comprising: a first communication interface coupled with a first network switch to receive at least one data access request requesting an access to the virtualized storage subsystem from one of the hosts that is coupled with the network switch; a second communication interface coupled with a second network switch to communicate with a first and a second storage subsystem including first and second storage areas, respectively, to store data associated with the access requesting host, the first and second storage subsystems being provided at remote locations from the storage server; and a virtual device driver component that is operable to present a virtual storage area of the virtualized storage subsystem to the access requesting host, the virtual storage area being mapped to the first storage area of the first storage subsystem prior to migration of data from the first storage subsystem to the second storage subsystem, wherein the storage server is configured to receive, from the access requesting host, a first data access request requesting reading of data stored in the virtualized storage subsystem, the first data access request including a storage address identifying a first location in the virtual storage area of the virtualized storage subsystem, to generate a second data access request directed to the first storage subsystem, the second data access request including a storage address identifying a second location in the first storage area that is mapped to the first location in the virtual storage area of the virtualized storage subsystem, to copy the data received from the first storage subsystem to a third location in the second storage area of the second storage subsystem, and to send the received data to the access requesting host, and wherein the storage server is configured to change mapping of the first location in the virtual storage area of the virtualized storage subsystem from the second location in the first storage area to the third location in the second storage area so that the access requesting host accesses the first storage subsystem and the second storage subsystem through the storage server.