Abstract: Disclosed is a storage system that achieves performance improvement, quality enhancement, and function addition requiring a drive data layout change while maintaining I/O functionality. The storage system creates a redundancy group for forming a redundant configuration of data to be stored in a storage drive, and stores data of the redundancy group in a plurality of the storage drives. A processor in a storage node discards data stored in a unit storage area, recovers the discarded data according to a changed data format, and re-stores the recovered data in the storage drive. The processor in the storage node performs an I/O process on the data to be discarded during a data format change, by achieving recovery based on the data of the redundancy group that is stored in an area other than the unit storage area where the data format is to be changed.

Abstract: The invention is to efficiently exchange storage programs. A storage program in an active state and a storage program in a standby state in a storage program group each change metadata thereof when the storage program in the active state writes data. When update of the storage programs including arranging post-update storage programs in storage nodes and generating new-version metadata based on old-version metadata by the post-update storage programs is to be performed, the post-update storage program in the standby state generates the new-version metadata based on the old-version metadata is performed for the storage programs in the plurality of storage nodes while replacing the active state and the standby state of the storage programs with each other in the plurality of storage programs in the storage program group.

Abstract: In a storage system in which a plurality of pieces of control software constituting a redundancy group are distributedly arranged in a plurality of storage nodes, control software in an active state out of the plurality of pieces of control software constituting the redundancy group receives a write request from a higher-level device. The control software in the active state writes data related to the write request by mirroring into a cache memory of a storage node in which the control software in the active state is arranged and a cache memory of a storage node in which control software in an inactive state belonging to the same redundancy group is arranged. The control software in the active state sends a write completion response to the higher-level device, and redundantly stores the data written in the cache memories in a storage device.

Abstract: When a communication protocol is changed, the I/O function can be appropriately provided. In a computer system, a storage node includes a CPU and a storage control program that performs communication relating to data I/O. The storage control program has a first storage control program that is capable of using a first communication protocol, and a second storage control program that is capable of using the first communication protocol and a second communication protocol. The control node the control node causes, when any storage node of the plurality of storage nodes is capable of executing the first storage control program alone, all storage nodes to perform communication using the first communication protocol. The control node causes, after all storage nodes of the plurality of storage nodes are enabled to execute the second storage control program, the all storage nodes to perform communication using the second communication protocol.

Abstract: In each node constituting a storage system, there is at least one of a storage area (user area) in which a user data set is stored and a storage area (parity area). For the node having the user area, there is user part difference information including information indicating whether or not to be in presence of difference for each user area of the node. For the node having the parity area, there is parity part difference information including the information indicating whether or not to be in the presence of difference for each parity area of the node. Out of the parity part difference information, the information corresponding to the parity area is the information indicating the presence of difference when there is the information indicating the presence of difference in the storage area of any of the data sets used for generating the parity stored in the parity area.

Abstract: The invention is to efficiently exchange storage programs. A storage program in an active state and a storage program in a standby state in a storage program group each change metadata thereof when the storage program in the active state writes data. When update of the storage programs including arranging post-update storage programs in storage nodes and generating new-version metadata based on old - version metadata by the post-update storage programs is to be performed, the post-update storage program in the standby state generates the new-version metadata based on the old-version metadata is performed for the storage programs in the plurality of storage nodes while replacing the active state and the standby state of the storage programs with each other in the plurality of storage programs in the storage program group.

Abstract: Each redundancy group is constituted by one active program (storage control software of the active program) and N standby programs (N is an integer of two or more). Each of the N standby programs is associated with a priority to be determined as a failover (FO) destination. In the same redundancy group, FO is performed from the active program to the standby program based on the priority. For the plurality of pieces of storage control software including the active programs and the standby programs that change to be active by FO in the plurality of redundancy groups arranged in the same node, standby storage control software that can set each of the programs as a FO destination are arranged in different nodes.

Abstract: In a storage system in which a plurality of pieces of control software constituting a redundancy group are distributedly arranged in a plurality of storage nodes, control software in an active state out of the plurality of pieces of control software constituting the redundancy group receives a write request from a higher-level device. The control software in the active state writes data related to the write request by mirroring into a cache memory of a storage node in which the control software in the active state is arranged and a cache memory of a storage node in which control software in an inactive state belonging to the same redundancy group is arranged. The control software in the active state sends a write completion response to the higher-level device, and redundantly stores the data written in the cache memories in a storage device.

Abstract: Each redundancy group is constituted by one active program (storage control software of the active program) and N standby programs (N is an integer of two or more). Each of the N standby programs is associated with a priority to be determined as a failover (FO) destination. In the same redundancy group, FO is performed from the active program to the standby program based on the priority. For the plurality of pieces of storage control software including the active programs and the standby programs that change to be active by FO in the plurality of redundancy groups arranged in the same node, standby storage control software that can set each of the programs as a FO destination are arranged in different nodes.

Abstract: When a communication protocol is changed, the I/O function can be appropriately provided. In a computer system, a storage node includes a CPU and a storage control program that performs communication relating to data I/O. The storage control program has a first storage control program that is capable of using a first communication protocol, and a second storage control program that is capable of using the first communication protocol and a second communication protocol. The control node the control node causes, when any storage node of the plurality of storage nodes is capable of executing the first storage control program alone, all storage nodes to perform communication using the first communication protocol. The control node causes, after all storage nodes of the plurality of storage nodes are enabled to execute the second storage control program, the all storage nodes to perform communication using the second communication protocol.

Abstract: To appropriately access data managed before a supply of power is stopped. A storage device that receives an I/O request from a host computer and performs an I/O processing in response to the I/O request includes a CPU, a nonvolatile medium, and a memory having access performance higher than that of the nonvolatile medium. The CPU stores control information about a control for performing the I/O processing in the memory and the nonvolatile medium. The control information stored in the nonvolatile medium includes address conversion information for converting a physical address of a drive in which target data of the I/O request is stored and a logical address that indicates a logical area of data stored in the physical address.

Abstract: Two or more nodes respectively provided with two or more storage control programs constituting each redundantization group maintain redundantization of metadata at the two or more nodes. When a node failure occurs, a failover from the corresponding active storage control program to a standby storage control program is performed. As regarding at least one standby storage control program, a node with the standby storage control program arranged therein compresses a target metadata portion including a metadata portion capable of being accessed after the failover, of metadata existing in the node as regarding the corresponding redundantization group, and stores the same in a memory of the node.

Abstract: Each redundancy group is constituted by one active program (storage control software of the active program) and N standby programs (N is an integer of two or more). Each of the N standby programs is associated with a priority to be determined as a failover (FO) destination. In the same redundancy group, FO is performed from the active program to the standby program based on the priority. For the plurality of pieces of storage control software including the active programs and the standby programs that change to be active by FO in the plurality of redundancy groups arranged in the same node, standby storage control software that can set each of the programs as a FO destination are arranged in different nodes.

Abstract: Each redundancy group is constituted by one active program (storage control software of the active program) and N standby programs (N is an integer of two or more). Each of the N standby programs is associated with a priority to be determined as a failover (FO) destination. In the same redundancy group, FO is performed from the active program to the standby program based on the priority. For the plurality of pieces of storage control software including the active programs and the standby programs that change to be active by FO in the plurality of redundancy groups arranged in the same node, standby storage control software that can set each of the programs as a FO destination are arranged in different nodes.

Abstract: Two or more nodes respectively provided with two or more storage control programs constituting each redundantization group maintain redundantization of metadata at the two or more nodes. When a node failure occurs, a failover from the corresponding active storage control program to a standby storage control program is performed. As regarding at least one standby storage control program, a node with the standby storage control program arranged therein compresses a target metadata portion including a metadata portion capable of being accessed after the failover, of metadata existing in the node as regarding the corresponding redundantization group, and stores the same in a memory of the node.

Abstract: A data rebalance control system determines instruction contents for an entity having a rebalance function, based on the capacity information including information indicating a plurality of physical capacities corresponding to a plurality of storing devices which include at least one storing device having a compression function, coupled to one and more computers included in a computer system. The rebalance function of the entity is a function of rebalancing data so that the distribution of the plural logical capacities recognized by the entity, corresponding to the plural storing devices, may be a predetermined distribution. The determined instruction contents include a definition about the logical capacity distribution. The data rebalance control system transmits, to the entity, a rebalance instruction as an instruction to rebalance the data according to the above instruction contents.

Abstract: A computing system that can maintain reliability required of a storage program while causing the storage program to operate on an operating system (OS) is provided. A processor of the computing system executes an OS controlling a hardware device and a storage program operating on the OS and using the hardware device via the OS. The OS identifies an error status of the hardware device when receiving a notification of an error that has occurred to the hardware device, and notifies the storage program that operates on the OS of the error status when the error status satisfies a predetermined condition. The storage program determines error handling on the hardware device on the basis of the error status, and requests the OS to perform the determined error handling. The OS performs the determined error handling on the hardware device.

Abstract: To appropriately access data managed before a supply of power is stopped. A storage device that receives an I/O request from a host computer and performs an I/O processing in response to the I/O request includes a CPU, a nonvolatile medium, and a memory having access performance higher than that of the nonvolatile medium. The CPU stores control information about a control for performing the I/O processing in the memory and the nonvolatile medium. The control information stored in the nonvolatile medium includes address conversion information for converting a physical address of a drive in which target data of the I/O request is stored and a logical address that indicates a logical area of data stored in the physical address.

Abstract: The computer system executes a storage program that operates on an OS to provide a logical volume to a host. The computer system includes volume management information including information on a storage function to be applied to the logical volume provided by the storage program. Upon receiving an I/O request for the logical volume from the host, the OS determines whether it is necessary for the storage program to perform an I/O process on the basis of the information on the storage function to be applied to the logical volume by referring to the volume management information. When it is determined that the I/O process is necessary, the OS communicates with the storage program and the storage program executes the I/O process. When it is determined that it is not necessary for the storage program to perform the I/O process, the OS outputs an I/O response to the host.

Abstract: The storage system is capable of creating one or more virtual storage subsystems to which virtual resources having logically divided a processing capacity of the physical resources are allocated, and upon creating a virtual volume for receiving I/O requests from the host within the virtual storage subsystem, the virtual storage subsystem allocates the virtual resource to the virtual volume, and when an I/O request to the virtual volume is received from the host, performs processing related to the I/O request using the virtual resource having been allocated. According further to the storage system, after allocating the virtual resource to the virtual volume, the storage system raises a utilization rate of the virtual resource allocated to the virtual volume in a stepwise manner.