Patent ID: 7363437

Claim:
A shared/exclusive control scheme in a computer system, wherein said computer system includes two or more sites each of which includes a storage device system connected to a plurality of high-rank apparatuses via a network, said two or more sites being connected to each other via an inter-high-rank-apparatuses network, said storage device systems in said respective two or more sites being connected to each other via remote-copy lines, each of said high-rank apparatuses included in each of said sites including an arbitration-emulation execution unit and a clustering unit, and said shared/exclusive control scheme comprises the two-step arbitration of: a first step by said arbitration-emulation execution units of executing respective arbitrations within said respective sites thereby to determine respective arbitration-win high-rank apparatuses within said respective sites; and a second step by said arbitration-emulation execution units of executing, among said respective sites, an arbitration among said respective arbitration-win high-rank apparatuses within said respective sites thereby to determine an arbitration-win high-rank apparatus among said respective sites, wherein each of said high-rank apparatuses includes a remote-copy control module, each of said storage device systems including an arbitration-purpose disk device, wherein said clustering unit included in each of said high-rank apparatuses includes a cluster-control main unit and a cluster disk driver, wherein said arbitration-emulation execution unit including a SCSI-command trap module and an inter-sites arbitration-emulation control module, wherein said SCSI-command trap module traps a SCSI command issued from said cluster disk driver, issues said trapped SCSI command to said arbitration-purpose disk device, catches a return value of said trapped SCSI command from said arbitration-purpose disk device and issues said return value to said inter-sites arbitration-emulation control module based on a value indicated by said return value, and wherein said inter-sites arbitration-emulation control module, upon receipt of said return value of said trapped SCSI command from said SCSI-command trap module and volume state of an inter-sites remote-copy pair, causes said trapped SCSI command and said volume state of said inter-sites remote-copy pair, via said remote-copy control module, to correspond to each other in accordance with said value indicated by said return value.