Patent ID: 7757055
Filing Date: 2010-07-13
Classification: G06F

Abstract:
1. A data migration method for a storage system having a first storage subsystem connected to a host computer and a second storage subsystem, for migrating data from a first volume in the first storage subsystem to a second volume in the second storage subsystem, the data migration method comprising: a first step of forming a first path between the first storage subsystem and the second storage subsystem; a second step of the second storage subsystem reading unique information concerning the first volume; a third step of generating control information for associating the first volume with the second volume by using pair volume information including an identifier of the first and the second volume and the unique information; a fourth step of setting a target port to be connected to the host computer in the second storage subsystem; a fifth step of switching the host computer's connection destination from the first storage subsystem to the target port in the second storage subsystem; a sixth step of the second storage subsystem sending the unique information to the host computer in response to access from the host computer to the second volume via the target port so that the host computer can recognize the second volume as the first volume; and a seventh step of the second storage subsystem migrating data in the first volume to the second volume via the first path, after the connection destination has been switched from the first storage subsystem to the target port in the second storage subsystem, wherein the second storage subsystem accepts access from the host computer while data is being migrated from the first volume to the second volume based on the pair volume information, without change of the identifier of the first volume in the host computer.