摘要 |
A data management apparatus of a computer system comprises, as a retention rule for volume data, change-time identification information for identifying a point-in-time for changing a logical unit, and migration-destination unit specification information for specifying a migration-destination logical unit. An edge storage apparatus stores first identification information, which enables the identification of volume data in a logical unit, and second identification information, which enables the identification of a logical unit in a storage system after associating the first identification information and the second identification information with each other. A data management apparatus (A1) transfers the volume data from a migration-source logical unit to the migration-destination logical unit conforming to the migration-destination unit specification information subsequent to a point-in-time identified in accordance with the change-time identification information. The edge storage apparatus (B1) associates the second identification information, which enables the identification of the migration-destination logical unit, with the first identification information, and stores the associated information in a storage device. |