Storage system and method for migrating the same

摘要

The present invention provides a storage system capable of performing data migration without stopping the IO access from a host computer, without having to copy data in an external connection storage subsystem to a migration destination storage subsystem. A configuration information of a migration source volume in a migration source storage subsystem is migrated to the migration destination storage subsystem, and during migration, cache memories of the respective subsystems are used to duplicate and store write data from the host computer, and the migration destination storage subsystem reflects the write data to the external connection storage subsystem. Reading of data is also performed by the migration destination storage subsystem.

主权项

1. A storage system comprising a migration source storage subsystem, a migration destination storage subsystem and an external storage subsystem, wherein:
the storage system has a host computer and a management device connected thereto; the migration source storage subsystem includes a migration source cache memory, which is associated with an external volume composed of a storage device of an external storage subsystem and provided virtually to the host computer as a migration source volume; the migration destination storage subsystem includes a migration destination cache memory; wherein based on a data migration instruction output by the management device from the migration source storage subsystem to the migration destination storage subsystem; the storage system: associates and allocates the migration source volume to the migration destination storage subsystem as a migration destination volume; associates the migration destination volume to the external volume and virtually provides the same to the host computer; based on a purge command to the migration source cache memory, deletes stored data after reflecting the stored data in the external volume; after completing the purge command, restricts the access from the host computer to the external volume to pass through the migration destination storage; when a data write command is output from the host computer to the migration destination volume, stores a write data in the migration destination cache memory and the external volume, and also transfers the same to the migration source cache memory for storage therein; and performs data migration of a system configuration in the migration source storage subsystem to a system configuration in the migration destination storage subsystem.