Patent ID: 8533421

Claim:
A computer control method for controlling migration in a computer system comprising a storage system, a computer for storing data in the storage system, and a management computer, the storage system including a plurality of storage media constituting a plurality of storage areas, and a controller connected to the storage media, the management computer including an interface connected to a network, and a processor connected to the interface, comprising the steps of: making by the controller a first logical storage area and a second logical storage area correspond to at least one first storage medium and at least one second storage medium respectively in the plurality of storage media; allocating by the controller data storage areas to the first and second logical storage areas from the first and second storage media respectively in accordance with a write request from the computer; setting by the controller the allocated second logical storage area as an area to which data to be written from the computer into the first logical storage area are migrated; setting by the controller a pairing relation for migrating data from the first logical storage area to the second logical storage area; making by the controller of the storage system third and fourth logical storage areas correspond to the first and second storage media respectively; allocating by the controller data storage areas to the third and fourth logical storage areas from the first and second storage media respectively in accordance with a write request from the computer; setting by the controller the allocated fourth logical storage area as an area to which data to be written from the computer into the third logical storage area are migrated; setting, by the controller, a pairing relation for data migration from the third logical storage area to the fourth logical storage area; and outputting, by the processor to an output portion connected to the processor, a data migration status including information on the first and third logical storage areas and information on a virtual pool to which the second and fourth logical storage areas belong, wherein the information on the virtual pool includes information for managing allocation of a real physical volume to a virtual volume to expand an insufficient capacity of the virtual volume, wherein said information for managing allocation includes: (a) information regarding a relationship between the virtual pool and a plurality of destination virtual volumes and a data migration execution status; and (b) information regarding a total value of source really allocated capacity sum plus destination virtual pool allocated capacity for notifying an influence on other virtual volumes which are not the destination volumes; said method further comprising determining whether migration will be permitted based on a comparison of the total value of source really allocated capacity sum plus destination virtual pool allocated capacity with a destination virtual pool threshold.