Abstract: A storage system and storage migration method where migration may be carried out to an access destination of a host apparatus without stopping the exchange of data between the host apparatus and the storage apparatus. This system is provided with a host apparatus inputting and outputting requests for data, a migration source storage apparatus having logical unit(s) correlated to storage regions of physical devices for storing the data, a migration destination storage apparatus having logical unit(s). The system also has an editing unit for editing configuration control information relating to the logical unit(s) for the migration source so as to match with settings for the migration destination storage apparatus, an importing unit for importing edited configuration control information to the migration destination storage apparatus, and a mapping unit for mapping the logical unit(s) of the migration source to the logical unit(s) of the migration destination.

Abstract: The present invention transfers replication logical volumes between and among storage control units in a storage system comprising storage control units. To transfer replication logical volumes from a storage control unit to a storage control unit, a virtualization device sets a path to the storage control unit. The storage control unit prepares a differential bitmap in order to receive access requests. When the preparation completes, the virtualization device makes access requests to the storage control unit. The storage control unit hands over the access requests to the storage control unit. The storage control unit performs a process so that the access requests are reflected in a disk device and performs an emergency destage of storing data in a cache memory into disk device. When the emergency destage ends, the storage control unit connects to an external storage control unit and hands over access requests to the external storage control unit.

Abstract: The present invention transfers replication logical volumes between and among storage control units in a storage system comprising a plurality of storage control units. To transfer replication logical volumes from a storage control unit to a storage control unit, a virtualization device sets a path to the storage control unit. The storage control unit then prepares a differential bitmap in order to receive access requests. When the preparation is completed, the virtualization device makes access requests to the storage control unit. The storage control unit then hands over the access requests to the storage control unit. Subsequently, the storage control unit performs a process so that the access requests are reflected in a disk device and performs an emergency destage of storing data in a cache memory into disk device. When the emergency destage is ended, the storage control unit connects to an external storage control unit and hands over access requests to the external storage control unit.

Abstract: In a system where a first storage system and a second storage system are connected to a third storage system, when the first storage system virtualizes and provides a device in the third storage system as a device in its own storage system, update data stored in a cache in the first storage system is written into the device of the third storage system to be reflected, attributes of the device are transferred to the second storage system, and the second storage system virtualizes the device of the third storage system as a device of its own storage system.

Abstract: When a computer 10 receives a request from the client computer 30 to access snapshot files, the target device to be used is identified. The computer 10 makes a request to the identified target device TD for attachment of the logical device LDEV that stores the snapshot files for which access is requested. When the computer 10 receives notification that the attachment has ended from the storage device system 20, the identified target device is mounted on the directory in which the snapshot files are stored.

Abstract: A plurality of modules (1) and (2) comprise a plurality of virtual volumes with which the same volume identification number is associated. A module (2), which receives a write request from a computer, searches for an unallocated real area from among a plurality of real areas in the module (2) rather than from among a plurality of real areas in the other module (1) if a real area has not been allocated to a write-targeted virtual area in accordance with the write request. The module (2) allocates the real area retrieved from the module (2) to the write-targeted virtual area, and writes data according to the write request to this real area.

Abstract: There are a plurality of storage apparatuses including a first storage apparatus and a second storage apparatus. The first storage apparatus has a virtual volume composed of a plurality of virtual segments. At least the second storage apparatus has a pool composed of a plurality of real pages (real storage areas). The plurality of storage apparatuses each manage one or more pools including at least the pool in the second storage apparatus as one virtual pool. The virtual pool is composed of a plurality of virtual pages, and each virtual page corresponds to any of the real pages. The first storage apparatus receives a write command that specifies an address belonging to an unallocated virtual segment to which no virtual page is allocated, allocates a free virtual page from the virtual pool to the unallocated virtual segment, and writes data accompanying the write command to the real page corresponding to the allocated virtual page.

Abstract: Provided is a computer system capable equalizing the storage capacity immediately and reliably to multiple real logical areas dynamically providing storage capacity to virtual logical areas. This computer system is characterized by, during the course of executing an operation of dynamically allocating a storage area to a virtual volume in response to an access from a host system, detecting an occasion where balance of a storage capacity among a plurality of logical areas is disrupted; and subsequently moving the storage area among a plurality of logical areas to maintain balance of the storage capacity.

Abstract: There is a journal area and one or more logical volumes comprising a first logical volume. The journal area is a storage area in which is stored a journal data element, which is a data element that is stored in any storage area of a plurality of storage areas configuring a logical volume, or a data element that is written to the storage area. A controller has a size receiver that receives a write unit size, which is the size of a write data element received from a computer, and a size setting unit that sets the received write unit size in a memory for one or more logical volumes. The size of a journal data element stored in a journal area based on the set write unit size is the write unit size.

Abstract: A virtual storage system is equipped with a plurality of storage systems and a virtualization device for virtualizing the plurality of storage systems logically into a single storage resource provided to a host computer. When one of the storage systems receives a command from the host computer, in the event that the storage system itself is not in possession of a function corresponding to the command, the storage system retrieves a storage system in possession of a function corresponding to the command and transfers this command to the storage system in possession of the function corresponding to the command.

Abstract: A storage system writes a data element stored in a primary volume to a secondary volume constituting a volume pair with the primary volume in accordance with a selected storage mode, which is a data storage mode selected from a plurality of types of data storage modes. This storage system is provided with a function for switching the above-mentioned selected storage mode from a currently selected data storage mode to a different type of data storage mode.

Abstract: Multiple storage area groups into which multiple storage areas provided by multiple storage devices are classified with reference to storage area attributes are managed. The multiple logical volumes to which, in accordance with a write request to at least one address included in multiple addresses in the logical volume, at least one storage area included in the multiple storage areas is allocated are provided. In accordance with the access condition of the at least one address in the logical volume, the data written to the at least one address by the write request is migrated from the at least one storage area included in one of the multiple storage area groups to at least one storage area in another storage area group included in the multiple storage area groups.

Abstract: Provided are a computer system and its data control method that enable safe backup of data and reduction in the capacity of data to be backed up. A control processor refers to a differential and, if a differential bit is “0,” encrypts data of an online VOL with an encryption circuit by using key information, and transfers the encrypted data to a second storage system. If the differential bit is “1,” the control processor performs redundancy elimination processing to journal data, thereafter compresses the journal data with a compression circuit, encrypts the compressed journal data with an encryption circuit according to the key information, and transfers the journal data that was encrypted after compression to the second storage system.

Abstract: Provided is a technique for realizing allocation of pool areas to virtual volumes in accordance with the use environment of the user with proper cost, while improving the capacity efficiency of media. For this purpose, in the present invention, a pool is constituted by selecting or limiting combinations of tiers of media in the pool to be used (range of tiers that can be used in each pool) for each virtual volume set in a storage system (see FIG. 5).

Abstract: Multiple storage area groups into which multiple storage areas provided by multiple storage devices are classified with reference to storage area attributes are managed. The multiple logical volumes to which, in accordance with a write request to at least one address included in multiple addresses in the logical volume, at least one storage area included in the multiple storage areas is allocated are provided. In accordance with the access condition of the at least one address in the logical volume, the data written to the at least one address by the write request is migrated from the at least one storage area included in one of the multiple storage area groups to at least one storage area in another storage area group included in the multiple storage area groups.

Abstract: The computer system includes a storage device, a virtual volume, a plurality of logical volumes each including a storage area and constituting a pool, and a controller for controlling the allocation of the storage area from the logical volumes in the pool to the virtual volume. The controller is configured to: manage, for each of the plurality of logical volumes in the pool, a capacity of the logical volume and a number of units of storage areas allocated to the virtual volume; allocate one or more units of storage area not allocated to virtual volume from the plurality of logical volumes in the pool to the virtual volume when it is necessary; detect a state where an imbalance occurs between the numbers of units of allocated storage areas of the logical volumes in the pool based on the managed information; and change the allocation in order to achieve a balance.

Abstract: A storage system writes a data element stored in a primary volume to a secondary volume constituting a volume pair with the primary volume in accordance with a selected storage mode, which is a data storage mode selected from a plurality of types of data storage modes. This storage system is provided with a function for switching the above-mentioned selected storage mode from a currently selected data storage mode to a different type of data storage mode.

Abstract: Multiple storage area groups into which multiple storage areas provided by multiple storage devices are classified with reference to storage area attributes are managed. The multiple logical volumes to which, in accordance with a write request to at least one address included in multiple addresses in the logical volume, at least one storage area included in the multiple storage areas is allocated are provided. In accordance with the access condition of the at least one address in the logical volume, the data written to the at least one address by the write request is migrated from the at least one storage area included in one of the multiple storage area groups to at least one storage area in another storage area group included in the multiple storage area groups.

Abstract: If an I/O load on a first virtual storage area falls below a first threshold, a controller copies data in a first storage area, which is allocated to the first virtual storage area, to a third storage area in a second tier storage area, and allocates the third storage area instead of the first storage area to the first virtual storage area. If an I/O load on a second virtual storage area exceeds a second threshold which is greater than said first threshold, the controller copies data in a second storage area, which is allocated to the second virtual storage area, to a fourth storage area in a first tier storage area, and allocates the fourth storage area instead of the second storage area to the second virtual storage area.

Abstract: The present invention allocates a suitable physical device to each volume page according to the state transition command relating to paired volumes. A plurality of logical devices forming a logical storage area of a plurality of physical devices of varying performance are tiered according to the performance of the physical devices to form a pool volume, and each of the areas of the primary logical volume, secondary logical volume and pool volume are managed by a controller, divided into a primary page, secondary page and pool page. Upon receiving a pair formation-related command from the host computer, the controller allocates pool pages belonging to the same tier to the primary page and secondary page, and upon subsequently receiving a pair-related state transition command, the controller allocates a pool page, in a different tier from the primary page, to the secondary page.