Data mapping management apparatus

A method for managing data mapping in a computer system including:

• a host computer for executing an application program which accesses to data files, said host computer including a file system and a volume manager, said file system being operatively coupled to said application program for converting accesses to the data files by said application program into accesses to first logical data volumes, and said volume manager being operatively coupled to said file system for converting accesses to the first logical data volumes into accesses to first virtual data volumes;
• a first virtual switch in communication with said volume manager via a network for converting accesses to the first virtual data volumes into accesses to second virtual data volumes;
• a second virtual switch in communication with said first virtual switch via the network, for converting accesses to the second virtual data volumes into accesses to second logical data volumes;
• storage subsystems in communication with said second virtual switch via the network, said storage subsystems including a plurality of disk drives and a controller for controlling the disk drives, said controller converting accesses to the second logical data volumes into accesses to physical data blocks of the disk drives, whereby said file system, said volume manager, said first virtual switch, said second virtual switch and said storage subsystems are layered in order from a highest layer to a lowest layer;
• and
• a data mapping management server operatively coupled to said host computer, said first virtual switch, said second virtual switch and said storage subsystems via the network, for selecting an access path of a data volume flowing from said file system to one of said storage subsystems through said first and second virtual switches by using a data mapping management table obtained by collecting a mapping information table stored in said volume manager, said first virtual switch and said second virtual switch, each mapping information table representing correspondence relationships between locations of data volumes inputted and locations of corresponding data volumes to be outputted,
• said method executed by said data mapping management server comprising steps of:
• receiving a command instructing migration of a logical data volume stored in one of said storage subsystems as a source storage subsystem to a new logical data volume stored in another storage subsystem as a destination storage subsystem;
• analyzing the mapping information tables to identify a virtual data volume to be migrated in said second virtual switch corresponding to the logical data volume to be migrated in said source storage subsystem;
• creating a new virtual data volume in said second virtual switch so that the new virtual data volume is coupled to the new logical data volume of said destination storage subsystem;
• copying the logical data volume to be migrated to the new logical data volume;
• copying the virtual data volume to be migrated to the new virtual data volume according to migration of the logical data volume;
• and
• altering mapping information in the mapping information tables held in said first and second virtual switches and in the data mapping management table according to migration of the logical data volume from said source storage subsystem to said destination storage subsystem.