Patent ID: 11907746
Assignee: HITACHI, LTD.
Field: Computer technology (Electrical engineering)
Classification: CPC G | IPC G

Claim 0:
1. A compound storage system comprising:
a storage box having a plurality of storage devices; and
a plurality of servers capable of executing one or more virtual machines,
wherein the storage box stores a logical volume,
the virtual machines executable by the server include an application virtual machine (VM) that executes an application using the logical volume, and a controller VM that configures a controller capable of controlling read and write with respect to a logical volume for which the controller has a control right,
when a predetermined situation occurs in which an application VM of a migration source server is migrated to a predetermined migration destination server,
at least one processor of the one or more servers in the compound storage system is configured to:
migrate the application VM to the migration destination server,
migrate a control right of a logical volume used by the application VM to a controller VM of the migration destination server, and
transfer cache data stored in a cache memory of a controller VM of the migration source server of a logical volume used by the application VM to a cache memory of a controller VM of the migration destination server.