Abstract: In a storage system having a plurality of control units each connected with a plurality of disk units, it is provided that a replication is created in the volume of the disk units connected to different control units. The replication creation unit of a given control unit creates a replication in the volume of the disk unit connected to other control units in such a manner that the original volume information, the replication volume information in the control unit and information on the other control units are registered as volume pair information. Based on this volume pair information, a replication creation request is transmitted to the other control units.

Abstract: Information about remote copy target volumes of other storage systems 2 each having one and the same original volume V1 is registered for each remote copy target volume in advance. When there occurs a failure in a copy source storage system 2, a copy source volume for remote copy target volumes using the storage system 2 having a failure as their copy source is selected newly from the registered copy source volumes, and remote copy is resumed.

Abstract: A method for migrating from a source storage system to a target storage system includes defining a volume defined on a device to be migrated in the source storage system as an external volume to the target storage system; causing the host to access the volume on the drive to be migrated through an input/output port of the drive to be migrated as the external volume of the target storage system; blocking the other input/output port of the drive to be migrated while maintaining the access to the external volume of the target storage system; reconnecting the blocked input/output port with an interface in the target storage system; blocking the input/output port through which the external volume is being accessed, and connecting it with the interface in the target storage system; and implementing the drive to be migrated in the target storage system.

Abstract: Information about remote copy target volumes of other storage systems 2 each having one and the same original volume V1 is registered for each remote copy target volume in advance. When there occurs a failure in a copy source storage system 2, a copy source volume for remote copy target volumes using the storage system 2 having a failure as their copy source is selected newly from the registered copy source volumes, and remote copy is resumed.

Abstract: For a storage system having plural control units to which plural disk devices are connected, in the method for creating replication in a volume of the disk devices connected to different control units, when receiving update I/O of a replication source during an initial copy for replication, the reflection of update to the replication destination is performed on an extension of the same I/O. When a pair is divided after the completion of copying, the update position is retained on the differential bitmap disposed in the individual control units, and the differential bitmap is merged to one of the control units at a time of resynchronization to perform copy processing.

Abstract: For a storage system having plural control units to which plural disk devices are connected, in the method for creating replication in a volume of the disk devices connected to different control units, when receiving update I/O of a replication source during an initial copy for replication, the reflection of update to the replication destination is performed on an extension of the same I/O. When a pair is divided after the completion of copying, the update position is retained on the differential bitmap disposed in the individual control units, and the differential bitmap is merged to one of the control units at a time of resynchronization to perform copy processing.

Abstract: In a cluster storage system, storage areas scattered in a plurality of storage nodes are coupled into a single storage area for access by a host computer. The cluster storage system has a first storage node and a second storage node, each of which has a disk and a control processor for controlling input/output to/from the disk, and a host interface node for connecting the first and second storage nodes to a computer. The first storage node manages a storage area having a first storage area existing in the first storage node and a second storage area existing in the second storage node as a logical device. Upon receipt of an access request having identification information corresponding to the logical device from the computer, the host interface node forwards the access request to the first storage node.

Abstract: A method for migrating from a source storage system to a target storage system includes defining a volume defined on a device to be migrated in the source storage system as an external volume to the target storage system; causing the host to access the volume on the drive to be migrated through an input/output port of the drive to be migrated as the external volume of the target storage system; blocking the other input/output port of the drive to be migrated while maintaining the access to the external volume of the target storage system; reconnecting the blocked input/output port with an interface in the target storage system; blocking the input/output port through which the external volume is being accessed, and connecting it with the interface in the target storage system; and implementing the drive to be migrated in the target storage system.

Abstract: In a storage system having a plurality of control units each connected with a plurality of disk units, it is provided that a replication is created in the volume of the disk units connected to different control units. The replication creation unit of a given control unit creates a replication in the volume of the disk unit connected to other control units in such a manner that the original volume information, the replication volume information in the control unit and information on the other control units are registered as volume pair information. Based on this volume pair information, a replication creation request is transmitted to the other control units.

Abstract: A pool, which has multiple pool regions which are storage regions capable of being dynamically allocated or released, is configured from a plurality of pool groups and a pool free region group which is common to the plurality of pool groups. Each of the pool groups is related to each storage control function of a storage system. When a used value of a certain pool group exceeds the threshold, a storage controller of the storage system selects a pool free region appropriate for the pool group from the pool free region group, and allocates the selected pool free region to the pool group.

Abstract: In a storage system having a plurality of control units each connected with a plurality of disk units, it is provided that a replication is created in the volume of the disk units connected to different control units. The replication creation unit of a given control unit creates a replication in the volume of the disk unit connected to other control units in such a manner that the original volume information, the replication volume information in the control unit and information on the other control units are registered as volume pair information. Based on this volume pair information, a replication creation request is transmitted to the other control units.

Abstract: When storage controllers are added to a storage system to change the storage system from a configuration having only one storage controller to a configuration having plural storage controllers, or when storage controllers are removed from the storage system to change the storage system from a configuration having plural storage controllers to a configuration having only one storage controller, a controller-internal management-information memory controller carries out a copy process to copy management information from each of the storage controllers to a management-information-memory switch or vice versa at the same time as processing of read and write requests for access to the management information, made by a channel interface or a disc interface, in order to change storage locations of the management information while processing the read and write requests made by the host.

Abstract: Information about remote copy target volumes of other storage systems 2 each having one and the same original volume V1 is registered for each remote copy target volume in advance. When there occurs a failure in a copy source storage system 2, a copy source volume for remote copy target volumes using the storage system 2 having a failure as their copy source is selected newly from the registered copy source volumes, and remote copy is resumed.

Abstract: Information about remote copy target volumes of other storage systems 2 each having one and the same original volume V1 is registered for each remote copy target volume in advance. When there occurs a failure in a copy source storage system 2, a copy source volume for remote copy target volumes using the storage system 2 having a failure as their copy source is selected newly from the registered copy source volumes, and remote copy is resumed.

Abstract: The present invention provides a method for migrating from a source storage system to a target storage system. The method comprises the steps of: defining a volume defined on a drive to be migrated in the source storage system as an external volume of the target storage system; causing the host to access the volume on the drive to be migrated through an input/output port of the drive to be migrated as the external volume of the target storage system; blocking the other input/output port of the drive to be migrated while maintaining the access to the external volume of the target storage system; reconnecting the blocked input/output port with an interface in the target storage system; blocking the input/output port through which the external volume is being accessed, and connecting it with the interface in the target storage system; and implementing the drive to be migrated in the target storage system.

Abstract: When data in the first primary volume is migrated to the second primary volume, an access request from the host to the primary volume is transferred to the second primary volume. Further, the second storage system stores write data received from the host and data of the first primary volume received from the storage system, into the second primary volume. Out of data stored in the second primary volume, the second storage system sends data determined by management information received from the first storage system, to the third storage system.

Abstract: When data in the first primary volume is migrated to the second primary volume, an access request from the host to the primary volume is transferred to the second primary volume. Further, the second storage system stores write data received from the host and data of the first primary volume received from the storage system, into the second primary volume. Out of data stored in the second primary volume, the second storage system sends data determined by management information received from the first storage system, to the third storage system.

Abstract: The present invention provides a method for migrating from a source storage system to a target storage system. The method comprises the steps of: defining a volume defined on a drive to be migrated in the source storage system as an external volume of the target storage system; causing the host to access the volume on the drive to be migrated through an input/output port of the drive to be migrated as the external volume of the target storage system; blocking the other input/output port of the drive to be migrated while maintaining the access to the external volume of the target storage system; reconnecting the blocked input/output port with an interface in the target storage system; blocking the input/output port through which the external volume is being accessed, and connecting it with the interface in the target storage system; and implementing the drive to be migrated in the target storage system.

Abstract: Information about remote copy target volumes of other storage systems 2 each having one and the same original volume V1 is registered for each remote copy target volume in advance. When there occurs a failure in a copy source storage system 2, a copy source volume for remote copy target volumes using the storage system 2 having a failure as their copy source is selected newly from the registered copy source volumes, and remote copy is resumed.

Abstract: The present invention provides a method for migrating from a source storage system to a target storage system. The method comprises the steps of: defining a volume defined on a drive to be migrated in the source storage system as an external volume of the target storage system; causing the host to access the volume on the drive to be migrated through an input/output port of the drive to be migrated as the external volume of the target storage system; blocking the other input/output port of the drive to be migrated while maintaining the access to the external volume of the target storage system; reconnecting the blocked input/output port with an interface in the target storage system; blocking the input/output port through which the external volume is being accessed, and connecting it with the interface in the target storage system; and implementing the drive to be migrated in the target storage system.