Abstract: A first controller manages first mapping information for accessing data stored in a storage area, management of which is assigned to the first controller, and second mapping information for accessing data stored in a predetermined storage area, management of which is assigned to a second controller. The second controller, when having executed garbage collection on the predetermined storage area, changes mapping information to post-migration mapping information for accessing data after being migrated by the garbage collection.

Abstract: Each controller of a plurality of storage controllers is an old storage controller before replacement or a new storage controller after replacement. The new storage controller can execute a first program and a second program, and the old storage controller can execute at least the second program. When all of the plurality of storage controllers are the new storage controller, the new storage controller processes data input and output to and from the storage drive by using the first program. When the plurality of storage controllers includes at least one of the old storage controllers, each storage controller of the plurality of storage controllers processes the data input and output to and from the storage drive by using the second program.

Abstract: A storage system comprises nodes and drives, and includes at least one mounting area to install the drives. A node manages a parity group constituted of the plurality of drives; generates, in a case where a target drive that is installed in a first mounting area and that belongs to a first parity group is to be moved from the first mounting area to a second mounting area, difference information regarding a storage area where data was written into the target drive during a period in which the target drive is moved from the first mounting area to the second mounting area; and restore data written into the storage area by using data stored in other drives than the target drive that belongs to the first parity group based on the difference information, and write the data into the target drive that has been moved to the second mounting area.

Abstract: A volume to which a storage function is applied is migrated without copying data written to a volume as a migration object between computers while maintaining functionality of the storage function. A plurality of computers are accessibly connected to each of one or more physical storage devices. Each computer migrates ownership of the volume as the migration object to a computer as a destination. When the migration object volume from a first computer to a second computer is an owner volume to which a storage function is applied, the storage function requiring control data for I/O of data, the control data being metadata other than domain mapping data (indicating a relationship between a volume region and a storage region and being metadata for the owner volume), in place of or in addition to the domain mapping data.

Abstract: A first node receives a read request, determines a storage drive location where data corresponding to one or more logical addresses designated in the read request is stored, and requests transfer of the data at the one or more logical addresses, from the second node, when the storage drive location is the second node. The second node reads a data chunk containing the data designated by the one or more logical addresses, from one or more storage drives, determines whether to decompress the data chunk based on the size of the data chunk and the size of the one or more logical addresses, decompresses the data chunk based on the determination as to decompress the data chunk, extracts data at the one or more logical addresses, and transfers the extracted data to the first node.

Abstract: In a multi controller storage system, hardware and software are updated without interruption. The storage system including a node has storage control units each including a processor, a memory, and a port; and a storage drive, and the storage control units each request data access and transmit and receive data with respect to a host computer via the ports. The processors process input and output data from the host computer, the memories store the control information in order to access the data stored in the storage drive, and the storage system transmits the control information stored in the memories to another node, stores the control information in the memories of the storage control units, and sets ports of the other node in consideration of a relationship between the storage control units and the ports of the nodes, if the other node can access data relating to the control information.

Abstract: A storage system includes: a storage drive having a storage medium storing a data; and a plurality of storage control units having a processor, a memory, and a port to process the data input and output to and from the storage drive, in which information related to a list of the storage control units mounted on the storage system and a maximum number of the storage control units that can be mounted on the storage system is allowed to be stored, and in which, when the storage control unit is replaced, it is determined whether the configuration to be migrated from the storage control unit to be reduced to the storage control unit to be added is migrated directly or via another storage control unit based on the number of the mounted storage control units and the maximum number of the storage control units that can be mounted.

Abstract: The present disclosure is to optimize processes in a storage system. A storage system includes: a first controller including a first computing device and a first memory; a second controller including a second computing device and a second memory; and an interface circuit that transfers data between the first controller and the second controller. The interface circuit reads first compressed data from the second memory. The interface circuit decompresses the first compressed data to generate first uncompressed data, and writes the first uncompressed data into the first memory.

Abstract: A first node receives a read request, determines a storage drive location where data corresponding to one or more logical addresses designated in the read request is stored, and requests transfer of the data at the one or more logical addresses, from the second node, when the storage drive location is the second node. The second node reads a data chunk containing the data designated by the one or more logical addresses, from one or more storage drives, determines whether to decompress the data chunk based on the size of the data chunk and the size of the one or more logical addresses, decompresses the data chunk based on the determination as to decompress the data chunk, extracts data at the one or more logical addresses, and transfers the extracted data to the first node.

Abstract: To improve performance of a storage system. The storage system includes a plurality of storage nodes that communicate via a network. Each of the plurality of storage nodes includes one or more controllers. At least one controller in the controllers specifies at least two controllers that allocate a cache sub-area where write data is stored based on a controller that receives the write data from a host and a controller that processes the write date, and the cache sub-area is allocated in the specified controllers.

Abstract: A storage system holds upper mapping information and lower mapping information. The upper mapping information manages an address relationship between a logical device upper layer accessed by a host and a logical device middle layer. The lower mapping information manages an address relationship between the logical device middle layer and a logical device lower layer. The lower mapping information includes pieces of partial mapping information. Each of the pieces of partial mapping information manages address information of a partial area in the logical device middle layer. The storage system writes, in response to a failure of first partial mapping information in the lower mapping information, new data that fills a first partial area in the logical device middle layer managed by the first partial mapping information, and regenerates the first partial mapping information.

Abstract: A storage system comprises nodes and drives, and includes at least one mounting area to install the drives. A node manages a parity group constituted of the plurality of drives; generates, in a case where a target drive that is installed in a first mounting area and that belongs to a first parity group is to be moved from the first mounting area to a second mounting area, difference information regarding a storage area where data was written into the target drive during a period in which the target drive is moved from the first mounting area to the second mounting area; and restore data written into the storage area by using data stored in other drives than the target drive that belongs to the first parity group based on the difference information, and write the data into the target drive that has been moved to the second mounting area.

Abstract: In a complex system including; one or more storage systems including a cache and a storage controller; and one or more storage boxes including a storage medium, the storage box generates redundant data from write data received from a server, and writes the write data and the redundant data to the storage medium. The storage box transmits the write data to the storage system when it is difficult to generate the redundant data or it is difficult to write the write data and the redundant data to the storage medium. The storage system stores the received write data in the cache.

Abstract: A first controller manages first mapping information for accessing data stored in a storage area, management of which is assigned to the first controller, and second mapping information for accessing data stored in a predetermined storage area, management of which is assigned to a second controller. The second controller, when having executed garbage collection on the predetermined storage area, changes mapping information to post-migration mapping information for accessing data after being migrated by the garbage collection.

Abstract: One or a plurality of physical storage devices that provide a physical storage area are connected to first and second computers. The computer updates metadata indicating the address correspondence relationship between the logical address of the volume and the physical address of the physical storage area in the write processing performed based on a write request designating the volume. The first computer copies the metadata to the second computer while receiving the write request. When the address correspondence relationship indicated by the copied metadata portion is changed during copying of the metadata, the first computer updates the metadata portion and copies the metadata portion to the second computer.

Abstract: The present disclosure is to optimize processes in a storage system. A storage system includes: a first controller including a first computing device and a first memory; a second controller including a second computing device and a second memory; and an interface circuit that transfers data between the first controller and the second controller. The interface circuit reads first compressed data from the second memory. The interface circuit decompresses the first compressed data to generate first uncompressed data, and writes the first uncompressed data into the first memory.

Abstract: The present disclosure is to optimize processes in a storage system. A storage system includes: a first controller including a first computing device and a first memory; a second controller including a second computing device and a second memory; and an interface circuit that transfers data between the first controller and the second controller. The interface circuit reads first compressed data from the second memory. The interface circuit decompresses the first compressed data to generate first uncompressed data, and writes the first uncompressed data into the first memory.

Abstract: In a multi controller storage system, hardware and software are updated without interruption. The storage system including a node has storage control units each including a processor, a memory, and a port; and a storage drive, and the storage control units each request data access and transmit and receive data with respect to a host computer via the ports. The processors process input and output data from the host computer, the memories store the control information in order to access the data stored in the storage drive, and the storage system transmits the control information stored in the memories to another node, stores the control information in the memories of the storage control units, and sets ports of the other node in consideration of a relationship between the storage control units and the ports of the nodes, if the other node can access data relating to the control information.

Abstract: A volume to which a storage function is applied is migrated without copying data written to a volume as a migration object between computers while maintaining functionality of the storage function. A plurality of computers are accessibly connected to each of one or more physical storage devices. Each computer migrates ownership of the volume as the migration object to a computer as a destination. When the migration object volume from a first computer to a second computer is an owner volume to which a storage function is applied, the storage function requiring control data for I/O of data, the control data being metadata other than domain mapping data (indicating a relationship between a volume region and a storage region and being metadata for the owner volume), in place of or in addition to the domain mapping data.

Abstract: One or a plurality of physical storage devices that provide a physical storage area are connected to first and second computers. The computer updates metadata indicating the address correspondence relationship between the logical address of the volume and the physical address of the physical storage area in the write processing performed based on a write request designating the volume. The first computer copies the metadata to the second computer while receiving the write request. When the address correspondence relationship indicated by the copied metadata portion is changed during copying of the metadata, the first computer updates the metadata portion and copies the metadata portion to the second computer.