Patent ID: 7600047
Filing Date: 2009-10-06
Classification: G06F

Abstract:
1. A storage controller which accesses a plurality of Internet Small Computer System Interface (iSCSI) devices via a network, the storage controller comprising: a processor; a memory; a storage device; and an iSCSI interface to each of the iSCSI devices, wherein the processor accesses each of the iSCSI devices via a router on the network, obtains security information which indicates safety of routes from the iSCSI devices to the storage controller as determined based on a number of incidences on the network for each of the iSCSI devices, or obtains transfer speeds which indicate data transfer speeds to transfer data from the iSCSI devices, said transfer speeds each being a data transfer speed which is expected when accessing one of the iSCSI devices, on the network at the time of test accessing to each iSCSI device or at a time of test accessing to the router, said security information and/or said transfer speeds being obtained when the processor is connected to each iSCSI device, wherein the processor updates ranking information in a device list based on the obtained security information and/or said transfer speeds, selects an optimum iSCSI device on the network based on the ranking information, and establishes connection to the selected iSCSI device via the network, wherein the processor reassigns, if the ranks are updated after selecting the optimum iSCSI device, new ranks to the iSCSI devices according to update information to generate re-ranking information, selects the optimum iSCSI device based on the re-ranking information, and accesses the selected optimum iSCSI device, wherein if an update is not necessary, then a check is performed to determine whether or not device list update information received from an external location exists, wherein if an update is necessary, then the ranks are re-assigned to the devices in accordance with the update information, and wherein if an update depending on the update information is not necessary, then a check is performed to determine whether or not a device request for any one of a device addition, a backup or a remote copy is issued, if a device request is issued, then a connection is established to the iSCSI device with the highest rank and that device is registered, and then the data access is carried out for the optimum device in the device list.