Abstract: In an environment in which plural external storage devices having different function control interfaces are intermixed, when a function of a storage device is controlled from a computer, a common interface for controlling the function of the storage device is provided. A device that provides the common interface manages an interrelationship between a storage area recognized by a host computer and a storage area provided by the storage device and associates a storage area which becomes a target of a function control instruction with the storage device that provides the storage area. A type of the storage device that provides the storage area which becomes the target of the function control instruction is identified and function control is ordered through a function control interface unique to the device.

Abstract: A host and a storage system each keep a shared identifier indicating a state of a system. The storage system acquires, at update of data, a data pair including data for a change through processing of the host and data before the update. The storage system relates the data pair to a shared identifier. When the host indicates an identifier, the storage system restores data using the data pair.

Abstract: Availability of an information system including a storage system that performs remote copy between two or more storage apparatuses and a host computer using such storage system is improved. A third storage apparatus including a third volume is coupled to a first storage apparatus, a fourth storage apparatus including a fourth volume is coupled to a second storage apparatus, the first and third storage apparatuses perform remote copy of copying data stored in a first volume to the third volume, the first and second storage apparatuses perform remote copy of copying data stored in the first volume to a second volume, and the third and fourth storage apparatuses perform remote copy of copying data stored in the third volume to the fourth volume.

Abstract: Provided is a storage system capable of starting/stopping a disk drive. At the time of allocating a logical device, it is judged, based on attributes including a purpose of the logical device, whether or not control can be performed in terms of start/stop of an allocation target disk drive to determine an allocation destination disk drive. Further, in the case where access to a specific logical device is stopped due to release of a path definition or other such cause, it is judged whether or not a disk drive corresponding to the logical device can be stopped. When it is judged that the disk drive can be stopped, the disk drive is stopped. When it is judged that the disk drive cannot be stopped, the logical device is migrated to another disk drive that can be stopped, a migration destination disk drive is stopped.

Abstract: A host I/F unit has a management table for managing an MPPK which is in-charge of the control of input/output processing for a storage area of an LDEV, and if a host computer transmits an input/output request for the LDEV, the host I/F unit transfers the input/output request to the MPPK which is in-charge of the input/output processing for the LDEV based on the management table, an MP of the MPPK performs the input/output processing based on the input/output request, and the MP of the MPPK also judges whether the MPPK that is in-charge of the input/output processing for the LDEV is to be changed, and sets the management table so that an MPPK which is different from the MPPK that is in-charge is to be in-charge of the input/output processing for the LDEV.

Abstract: A method for controlling a storage system including a host computer, and a first and a second storage control apparatuses each receiving a data input/output request from the host computer and executing a data input/output process for a storage device in response to the request, comprises connecting a first communication path between the host computer and the first apparatus; connecting a second communication path between the first apparatus and the second apparatus; receiving by the first apparatus a first data input/output request from the host computer through the first path; when the first apparatus has judged that the first request is not for the first apparatus, transmitting by the first apparatus a second data input/output request corresponding to the first request, to the second apparatus through the second path; and by the second apparatus, receiving the second request and executing a data input/output process corresponding to the second request received.

Abstract: Availability of an information system including a storage system that performs remote copy between two or more storage apparatuses and a host computer using such storage system is improved. A third storage apparatus including a third volume is coupled to a first storage apparatus, a fourth storage apparatus including a fourth volume is coupled to a second storage apparatus, the first and third storage apparatuses perform remote copy of copying data stored in a first volume to the third volume, the first and second storage apparatuses perform remote copy of copying data stored in the first volume to a second volume, and the third and fourth storage apparatuses perform remote copy of copying data stored in the third volume to the fourth volume.

Abstract: The data up to a point of time whereat failure has occurred will be restored at high speed at a remote site without imposing any burden on a host. The first storage system on the master side processes an I/O request from the host, and as a result of I/O processing to the second storage system on the remote side, transmits the update data. The second storage system retains data received from the first storage system as update log data. The host transmits a command for settling a state of an application to the first storage system as data, and the first storage system transmits the data to the second storage system. The host and the second storage system both retain an identifier corresponding to the command, and relate the identifier to the log data. Thereby, the host designates the identifier at any given time, whereby the second storage system restores the data at any given time.

Abstract: A host I/F unit has a management table for managing an MPPK which is in-charge of the control of input/output processing for a storage area of an LDEV, and if a host computer transmits an input/output request for the LDEV, the host I/F unit transfers the input/output request to the MPPK which is in-charge of the input/output processing for the LDEV based on the management table, an MP of the MPPK performs the input/output processing based on the input/output request, and the MP of the MPPK also judges whether the MPPK that is in-charge of the input/output processing for the LDEV is to be changed, and sets the management table so that an MPPK which is different from the MPPK that is in-charge is to be in-charge of the input/output processing for the LDEV.

Abstract: Provided is a storage system capable of starting/stopping a disk drive. At the time of allocating a logical device, it is judged, based on attributes including a purpose of the logical device, whether or not control can be performed in terms of start/stop of an allocation target disk drive to determine an allocation destination disk drive. Further, in the case where access to a specific logical device is stopped due to release of a path definition or other such cause, it is judged whether or not a disk drive corresponding to the logical device can be stopped. When it is judged that the disk drive can be stopped, the disk drive is stopped. When it is judged that the disk drive cannot be stopped, the logical device is migrated to another disk drive that can be stopped, a migration destination disk drive is stopped.

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: A migration destination storage creates an expansion device for virtualizing a migration source logical unit. A host computer accesses an external volume by way of an access path of a migration destination logical unit, a migration destination storage, a migration source storage, and an external volume. After destaging all dirty data accumulated in the disk cache of the migration source storage to the external volume, an expansion device for virtualizing the external volume is mapped to the migration destination logical unit.

Abstract: A first storage system is connected to a second storage system, and an external device within the first storage system is provided to a host as a device of the second storage system. The second storage system includes a cache control section having cache adaptors, each controlling a disk and a cache, a protocol conversion section including protocol adaptors that switch requests from the host to appropriate ones of the cache adaptors, a management adaptor, and an internal network that mutually connects the cache adaptors, the protocol adaptors and the management adaptor. The first storage system being connected to any of the protocol adaptors is connected to the second storage system. The second storage system executes a processing for the external device by the cache control section, or connects to the first storage system through the protocol conversion section without the cache control section executing processing for the external device.

Abstract: A computer system, storage system, and device control method which keep and operate long-term data stored in a disk device using its characteristics for a long time and at low cost, in a storage system or in a storage system using an external storage connection method. A computer system comprises a host computer, a storage system, and a management server, which are connected to one another via a network. The storage system receives a request to detach a logical device, specifies a logical device to be processed with information included in the request and a physical device corresponding to the relevant logical device, releases a definition of a host path of the logical device, and stops the physical device.

Abstract: The data up to a point of time whereat failure has occurred will be restored at high speed at a remote site without imposing any burden on a host. The first storage system on the master side processes an I/O request from the host, and as a result of I/O processing to the second storage system on the remote side, transmits the update data. The second storage system retains data received from the first storage system as update log data. The host transmits a command for settling a state of an application to the first storage system as data, and the first storage system transmits the data to the second storage system. The host and the second storage system both retain an identifier corresponding to the command, and relate the identifier to the log data. Thereby, the host designates the identifier at any given time, whereby the second storage system restores the data at any given time.

Abstract: A migration destination storage creates an expansion device for virtualizing a migration source logical unit. A host computer accesses an external volume by way of an access path of a migration destination logical unit, a migration destination storage, a migration source storage, and an external volume. After destaging all dirty data accumulated in the disk cache of the migration source storage to the external volume, an expansion device for virtualizing the external volume is mapped to the migration destination logical unit.

Abstract: In a storage subsystem, performance tuning is performed with respect to all of the logical devices including external storage subsystems that are not directly connected to host computers. The physical storage units presented by the external storage subsystems are defined as logical devices of the storage subsystem, and I/O processing requests from the host computers are relayed to the logical devices. At the time of relaying, I/O processing conditions are monitored. When the load of an external storage subsystem is high, then operating conditions of ports and processors are examined. When the load can be reduced by changing the configuration of those ports and processors, the configuration is changed to reduce the load. When the load can not be reduced, data is migrated from a logical device having a high load to a logical device having a sufficient performance.

Abstract: Availability of an information system including a storage apparatus and a computer is improved. First and second storage apparatuses execute remote copy of copying data written into a first primary volume from the computer to a second primary volume, at least one of the first and second storage apparatuses executes local copy of copying the data written into the first or second primary volume in a self-storage apparatus to the corresponding first or second secondary volume, and the computer switches the destination of a write request of the data from the first storage apparatus to the second storage apparatus in case of a failure occurring in the first storage apparatus.

Abstract: In a storage subsystem, performance tuning is performed with respect to whole logical devices including external storage subsystems that are not directly connected to host computers. Physical storage units presented by the external storage subsystems are defined as logical devices of the storage subsystem itself, and I/O processing requests from the host computers are relayed to those logical devices. At the time of relaying, I/O processing conditions are monitored. When there exists an external storage subsystem whose load is high, then, operating conditions of ports and processors are examined. In the case where the load can be reduced by changing the configuration of those ports and processors, the configuration is changed to reduce the load. In the case where the load can not be reduced, data is migrated from a logical device having a high load to a logical device having a sufficient performance.

Abstract: Access to a plurality of logical devices is enabled regardless of the number of ports provided in a storage system and the number of logical devices that can be allocated to a single port, thereby improving the usability of the logical devices. A storage system comprises a plurality of logical devices, a target device which is the object of access from a computer, and a juke box system for allocating one of the plurality of logical devices to the target device. The juke box system changes the logical device that is allocated to the target device in accordance with a request from the computer.