Abstract: In a case of exchanging a migration source storage controller and a migration destination storage controller sharing one storage medium during replacement of storage devices, when hardware configurations or data management forms of the storage controllers are different, data in the storage medium cannot be shared even when data management information can be copied. Accordingly, a storage system, having a storage control unit and a storage drive provided with a storage medium, includes data management information for accessing data in the storage drive. A first storage control unit copies data management information about the data in the storage drive to a second storage control unit. When a write request is received from a host after copying of the data management information begins, each of the first storage and second storage control units stores write data related to the write request in a separate storage area of the storage drive.

Abstract: A virtual storage system according to an aspect of the present invention includes multiple storage systems each including: a storage controller that accepts a read/write request for reading or writing from and to a logical volume; and multiple storage devices. The storage system defines a pool that manages the storage device capable of allocating any of storage areas to the logical volume, and manages the capacity (pool capacity) of the storage areas belonging to the pool, and the capacity (pool available capacity) of unused storage areas in the pool. Furthermore, the storage system calculates the total value of the pool available capacities of the storage systems included in the virtual storage system, and provides the server with the total value as the pool available capacity of the virtual storage system.

Abstract: A gas detector comprises: plural gas sensors provided with a metal-oxide semiconductor whose resistance changes based upon contact with a gas; and a driving circuit for operating the gas sensors. The gas detector stores the ratio between initial resistance in air of the metal-oxide semiconductor and initial resistance of the metal-oxide semiconductor in an atmosphere including a predetermined concentration of fron gas, for the plural gas sensors. The gas detector learns resistance in air of the metal-oxide semiconductor in a gas sensor in use, and detects occurrence of fron gas when resistance of the metal-oxide semiconductor of the gas sensor in use becomes lower than a value corresponding to the learned resistance in air divided by the ratio. The gas detector counts the period that a first gas sensor is used.

Abstract: In a storage system, attributes of nodes are specified as first attribute nodes and second attribute nodes, the I/O processing in the nodes is executed as a plurality of processes including front-end I/O processing executed by any of the first attribute nodes and back-end I/O processing executed by the first and second attribute nodes having a storage device that stores data relating to the I/O processing.

Abstract: According to one embodiment, a storage system includes a representative node and a plurality of general nodes including a plurality of resources. Each of the general nodes stores resource status information indicating respective statuses of the plurality of resources in a first storage unit thereof. The representative node stores resource status information collected from the plurality of general nodes in a second storage unit thereof, decides whether to acquire the resource status information from the first storage unit of the general node or to acquire the resource status information from the second storage unit based on a received request, and transmits the resource status information acquired from a decided acquisition destination to an issuing source of the request.

Abstract: A storage system includes a storage controller, plural volumes each configured by the storage controller, and a pool allocating physical storage areas to logical storage areas of the volumes. The storage controller configures a first group including, among the volumes, a first primary volume to which a first target protection period is set, and a first history information volume storing history information about updating to the first primary volume, and a second group including, thereamong, a second primary volume to which a second target protection period is set, and a second history information volume storing history information about updating to the second primary volume. The volumes included in the first and second groups utilize the same physical storage area of the pool. When increasing a free capacity thereof, history information to be purged is determined from the first and second protectable periods such that their protectable periods become the same.

Abstract: A storage system and storage control method are provided in which a plurality of volumes to be processed by a storage control unit are distributed and evacuated in a normal storage control unit without recovering redundancy of the storage control unit having decreased redundancy, and the storage control unit itself having the decreased redundancy is deleted after the evacuating is completed, and thus reservation information processing resources for guaranteeing recoverability of the redundancy become unnecessary.

Abstract: The present invention provides a storage that enables all of a plurality of users to exercise snapshot management without causing a problem even in a situation where the plurality of users acquire snapshots of the same primary volume. Snapshots created through a plurality of interfaces are grouped. Grouping is performed at the time of snapshot creation. Snapshots in a group are required by other interfaces at a time when the snapshots are created. In a case where a deletion instruction is issued with respect to grouped snapshots, only the issuance of the deletion instruction is recorded without deleting snapshot data. In a case where the deletion instruction is issued with respect to all the snapshots in a group, the group is deleted because the snapshots in the group can be determined to be unnecessary for any user. After group deletion, snapshots instructed to be deleted and not grouped are deleted.

Abstract: A storage apparatus including a controller; a first volume provided to a host; and a second volume for storage of backup data or a snapshot image of the first volume. The controller periodically acquires the backup data or the snapshot image of the first volume at predetermined intervals; acquires monitoring information including access information of the host and a volume used capacity in the first volume and sets a normal state of the first volume in typical use using the acquired monitoring information; detects an access behavior in a volume deviating from the set normal state; and creates the backup data or the snapshot of the first volume in the second volume at a point in time of detection and sets a restore point to perform management.

Abstract: When a real area is allocated to a write destination virtual area in a virtual volume, a storage device determines whether or not a size of compressed new data is larger than a size of the allocated real area. In a case where the determination result is true, the storage device determines whether or not there is one or more real areas having a size equal to or larger than the size of the compressed new data and including a garbage area that is a real area serving as garbage. In a case where the determination result is true, the storage device selects one or more real areas including the garbage area, allocates, instead of the allocated real area, the selected one or more real areas to the write destination virtual area, and manages the allocated real area as a garbage area.

Abstract: According to one embodiment, a storage system includes a first storage device and a second storage device. In a case where the first storage device performs writing or updating of data on a first primary volume, the first storage device transmits the data to a second storage device based on a first replication pair. In a case where the first storage device creates or updates a second primary volume that is a snapshot of the first primary volume, the second storage device creates or updates a second secondary volume that is a snapshot of the first secondary volume configuring the first replication pair with the first primary volume.

Abstract: Provided is a storage controller that reduces a reference number to duplicate data even if there is duplicate data. The storage controller includes a memory and processor and is connected to a server and physical storage device. The memory stores a VOL management table, an address translation table, and a generation management table; registers a first provision volume and a first additional writing volume in the VOL management table; registers a reference destination of a first address of the first provision volume as a second address of the first additional writing volume in the address translation table. The processor receives a request for replication of the first provision volume; registers the second provision volume and the third provision volume in the generation management table as the child generation of the first provision volume; and processes the request to the first provision volume as a request to the third provision volume.

Abstract: A storage system and storage control method are provided in which a plurality of volumes to be processed by a storage control unit are distributed and evacuated in a normal storage control unit without recovering redundancy of the storage control unit having decreased redundancy, and the storage control unit itself having the decreased redundancy is deleted after the evacuating is completed, and thus reservation information processing resources for guaranteeing recoverability of the redundancy become unnecessary.

Abstract: A computer system includes a management computer, a first storage apparatus, and a second storage apparatus. A first logical device of the first storage apparatus and a second logical device of the second storage apparatus constitute a remote copy pair. The second logical device and a third logical device of the second storage apparatus constitute a copy pair. The second logical device and the third logical device have virtual IDs to be recognized by an issuer of an I/O request. The second storage apparatus interchanges the virtual IDs of the third logical device and the second logical device with reception of a command from the management computer as a trigger during processing of the I/O request from the issuer of the I/O request to the third logical device, thereby switching an access destination of the issuer of the I/O request from the third logical device to the second logical device.

Abstract: An information system connected to hosts and an information processing system manages a second ALU connected to the hosts via a second logical path, and second SLUs for receiving I/O requests from the hosts via the second logical path. A processor manages a first ALU connected to the hosts via a first logical path and first SLUs that receive I/O requests from the hosts via the first logical path, and builds up a first group including the first SLUs. A first SLU and a second SLU compose an HA pair, and the HA pair is provided to the hosts as one volume. The processor evaluates the state of the first logical path based on the pair state of the first SLU that composes the HA pair included in the first group so priorities with which the hosts issue I/Os to the first logical path can be determined.

Abstract: In order to create, at another site, a backup of a volume at a specific time point while minimizing the response time required to update the volume, a first storage apparatus and a second storage apparatus transfer a journal in a first journal volume to the second storage apparatus, the second storage apparatus writes the transferred journal into a second journal volume, the second storage apparatus reads journals in the second journal volume in order of the update, the second storage apparatus reflects the read journals to a second data volume, the first storage apparatus creates, in the first journal volume, a journal including a marker when a specific condition is satisfied, and the second storage apparatus creates a snapshot of the second data volume upon detecting a marker in the read journal.

Abstract: With omission of a duplication process of compressed data, a cache access frequency is reduced to improve throughput. A storage system includes first and second control units and a storage drive. Upon receiving a data write command, the first control unit stores data to be subjected to the write command in a first cache area of the first control unit, and stores the data in a second cache area of the second control unit to perform duplication, and upon completion of the duplication, the first control unit transmits a response indicating an end of write, performs a predetermined process on the data to be subjected to the write command, stores the data in a buffer area, reads the data stored in the buffer area, and transmits the read data to the storage drive.

Abstract: A storage device allocates an address area of an address space to the first virtual address space in accordance with writing onto a first virtual address space. A controller manages an address area in the first virtual address space, in which address area a mapping to the real address space has been removed, as a usage prohibition area. When a use state of the first virtual address space reaches a predetermined criterion, the controller or the storage device adds new continuous address areas to the first virtual address space to expand the first virtual address space. The storage device allocates an area, in which a mapping to the first virtual address space has been removed, to the first virtual address space expanded.

Abstract: Each of a storage apparatus having a primary volume and a storage apparatus having a secondary volume, upon reception of a write command, changes a data attribute of a data area allocated to an address designated by the write command, to a first attribute if the data attribute is other than the first attribute. In an offloaded data copy processing sequence, each of the storage apparatus changes a data attribute of a data area allocated to a copy source address to a second attribute if the data attribute is other than the second attribute. When an allocation information copy process is to be performed to allocate the data area to a copy destination address according to an offloaded data copy command, each of the storage apparatus discontinues the offloaded data copy processing sequence if the data attribute of the data area is the first attribute.

Abstract: A storage system capable of dynamically securing free space when a certain storage apparatus is disused and reducing the influence on the system upon dynamically securing the free space without having to continuously secure, in a memory of another storage apparatus, free space capable of storing management information of the corresponding storage apparatus in preparation of a case where such storage apparatus is disused. Each storage apparatus comprises a memory including a management information storage area for storing management information and a cache area for storing cache information, and a processor which manages a status of the cache area. At least certain processors determine a storage apparatus to become a copy destination of the copy target management information. The storage apparatus of the copy destination releases at least a part of the cache area and stores the management information in the released cache area.