Abstract: This storage system modifies the migration plan in accordance with the state of the migration destination when a plurality of volumes are migrated all at once. Migration-source volumes are migrated collectively to volumes inside the migration-destination storage apparatus. The user can make settings related to migration-source volumes and migration-destination volumes in a migration plan, and can establish a mid-process control plan for modifying the migration plan in the middle of processing. If a failure occurs in the migration-destination storage apparatus subsequent to the commencement of data migration processing, a processing method controller either cancels or temporarily halts the data migration processing, or changes the migration destination, on the basis of the mid-process control plan. When changing the migration destination, a previously selected alternate storage apparatus is selected as the new migration-destination storage apparatus.

Abstract: A common external storage device is connected to the first and second storage systems.

Abstract: Provided is a computer system capable of maintaining consistency of data stored in logical volumes. The computer system includes: a storage system including a disk controller which controls data read/write in a disk drive; and a host computer which transmits a request to the storage system, wherein the disk controller has a control unit and a storage unit, the disk drive has logical volumes which are data storing areas, the host computer sends a request directed to the logical volume and attribute information of the logical volume, the control unit wherein: executes the received request; the control unit stores, in the storage unit, the received attribute information in association with the logical volume; and decides to execute a following request which is made by the host computer to the logical volume in a case where the request meets the attribute information corresponding to the logical volume and is stored in the storage unit.

Abstract: When a storage system receives a request from a host computer to read data from a logical unit, the storage system selects a logical device from which data is to be read, in accordance with the power supply status and power-off time for each logical device allocated to the logical unit, turns on the power supply for the selected logical device, and reads data from that device. When the storage system receives a request from a host computer to write data to a logical unit, it turns on the power supply for each logical device allocated to the logical unit and performs multiplex-writing of data for each logical device.

Abstract: A computer system that is able to recover data at an arbitrary point in time using journals even after a data volume has been migrated between storage apparatuses. The computer system has a data recovery management unit create continuous journal data that ensures the continuity of journals before and after the migration of the data volume and, based on that continuous journal data, recovers the data.

Abstract: When there is a change in a group of volumes managed by a host computer, data duplication processing is immediately carried out against the changed volume. The host computer includes a volume-managing portion, a data duplication-controlling portion which executes the data duplication of data stored in a volume in a main data center, and a data duplication storing portion which stores data necessary for the data duplication. The data duplication-controlling portion compares data held by the volume-managing portion with the data in the data duplication storing portion, and updates the data in the data duplication storing portion based on the data held by the volume-managing portion.

Abstract: The computer system comprises a first and second computer, at least one first storage system connected to the first computer, and a plurality of second storage systems connected to the second computer as well as being connected to the at least one first storage system. The first computer issues to the first storage system a normal write request and control-use write request stamped with issue time. A control-use write request is issued at periodic intervals. The first storage system receives a write request and transmits the write request as update-data to second storage system in such a way that the issue order is ascertainable. The second storage system receives the update-data and, responsive to a reflect instruction from the second computer, reflects the update-data in storage areas.

Abstract: In a data processing system having a storage system and a management computer for managing the storage system, the management computer has an access right setting request unit for transmitting, to the storage system, a request to set a right to access a designated logical volume in response to a predetermined external input. The storage system also has: a control unit for dynamically expanding, as necessary based on an access request from the host computer, the capacity of a first type logical volume by dynamically assigning storage areas in units of segments of predetermined size thereto; and an access right setting unit for setting, in response to a request to set a right to access the first type logical volume from the management computer, a designated access right for each segment assigned to the first type logical volume.

Abstract: This invention relates to data backup and data recovery in a computer system. An outputting unit updates data stored in a first area based on an update request of data from the host computer, a creating unit stores update data for the update request in a second area, a marker processing unit creates a marker containing information of the range, in which the data is stored, and information indicating whether or not the data is allowed to be stored in a third area based on a request of creating the marker from the host computer to store the created marker in the second area, and a reflecting unit refers to the marker, obtains the update data corresponding to the data storing range, which is stored prior to the marker, and reflects the obtained update data to the third area.

Abstract: When migrating data stored in a storage region assigned to a volume to another storage region, the connection status of the host computer and volume is confirmed. When the host computer and volume are connected, the maximum capacity of the volume requested by the host computer is reserved so that it is exclusively secured in another storage region to which data is to be migrated, and when the host computer and volume are not connected, the current capacity of the volume is reserved so that it is exclusively secured in another storage region.

Abstract: Conventionally, it has been impossible to choose storage subsystems for selective implementation of I/O delay to prevent buffer from overflowing during remote copy. According to this invention, in a management computer that manages serially connected plural storage subsystems in a computer system, the computer system having a host computer to write data in the storage subsystems, the plural storage subsystems each have one or more logical volumes where data is stored and a buffer where data is stored temporarily, the logical volume of one of the storage subsystems and the logical volume of another of the storage subsystems form a pair for remote copy, and the management computer observes the usage of each buffer and issues, when the usage of the buffer exceeds a given threshold in a first storage subsystem, a command to delay executing write processing to the storage subsystems that are upstream of the first storage subsystem.

Abstract: Provided is a computer system management method capable of preventing a loop of pairs from being formed upon remote copy pair formation. The method of controlling formation of a remote copy pair of logical volumes in a computer system including a plurality of logical volumes includes: receiving a request to form a remote copy pair; judging whether or not a loop of remote copy pairs will be formed by executing the requested remote copy pair formation; and executing the requested remote copy pair formation when it is judged that no loop of copy pairs will be formed.

Abstract: Provided is a computer system capable of maintaining consistency of data stored in logical volumes. The computer system includes: a storage system including a disk controller which controls data read/write in a disk drive; and a host computer which transmits a request to the storage system, wherein the disk controller has a control unit and a storage unit, the disk drive has logical volumes which are data storing areas, the host computer sends a request directed to the logical volume and attribute information of the logical volume, the control unit wherein: executes the received request; the control unit stores, in the storage unit, the received attribute information in association with the logical volume; and decides to execute a following request which is made by the host computer to the logical volume in a case where the request meets the attribute information corresponding to the logical volume and is stored in the storage unit.

Abstract: In A computer system, the processing load for the computer to acquire fault information from the storage system is reduced. The computer system includes a computer, a first storage system configured to be communicable with the computer, and a second storage system configured to be communicable with the first storage system. The second storage system identifies the first storage system that is capable of communicating with the second storage system, detects fault occurring in the second storage system, and transmits fault information to the identified first storage system, the fault information being related to the detected fault. And the first storage system notifies the computer of the transmitted fault information.

Abstract: When collecting information about management of a storage of a disk subsystem, loads imposed on a host computer and a network are alleviated to improve the throughput of a computer system having the storage. The disk subsystem includes a CPU and a main memory and information on a disk is collected in response to a request from a management computer. An information collection program is operated on the disk subsystem, whereby, volume management information can be edited on the disk subsystem and utilized by the management computer.

Abstract: In a computer system, to enable a second computer to take over control of copying of data within the computer system, from a first computer that normally controls copying of data. The second computer selects from a plurality of storage systems a storage system to be accessed in order to acquire sub system pair information, and acquires sub system pair information from the selected storage system. Based on the acquired sub system pair information, the second computer generates system pair information that includes copy pair information relating to a plurality of storage areas belonging to the plurality of storage systems. The second computer initially selects a storage system directly linked to the second computer, and subsequently sequentially selects a storage system based on the acquired sub system pair information.

Abstract: Transfer of data and replication of data among several storage devices are executed without imposing a load on the computer connected to the storage system. For example, a first host computer monitors usage rates of transfer groups TG11, TG12 and physical path usage rate on a storage device interconnect physical path 50, and when either a usage rate or physical path usage rate goes above a predetermined value, issues to the first storage device 20 an instruction to allocate a reserved volume R11, R12. The first host adaptor 21 receiving the reserved volume R11, R12 allocation request allocates reserved volume R11 to transfer group TG1, whereby a virtual transfer volume is formed by transfer volume T11 and the reserved volume R11 allocated thereto. As a result, capacity of the virtual transfer volume is increased by the equivalent of the reserved volume R11 capacity, so that additional transfer frames may be stored.

Abstract: To provide a computer system capable of detecting a failure at an early stage while keeping down an increase in I/O load due to failure monitoring. The computer system includes plural storage systems connected in stages between a first computer and a second computer. The first computer sends control I/O to the storage systems. The second computer monitors control I/O transferred through the storage systems; and when there is control I/O that has not been transferred successfully, requests state information of the storage systems to transfer the control I/O.

Abstract: Transfer of data and replication of data among several storage devices are executed without imposing a load on the computer connected to the storage system. For example, a first host computer monitors usage rates of transfer groups TG11, TG12 and physical path usage rate on a storage device interconnect physical path 50, and when either a usage rate or physical path usage rate goes above a predetermined value, issues to the first storage device 20 an instruction to allocate a reserved volume Ri 1, R12. The first host adaptor 21 receiving the reserved volume Rh, R12 allocation request allocates reserved volume Ru to transfer group TGI, whereby a virtual transfer volume is formed by transfer volume Til and the reserved volume Ru allocated thereto. As a result, capacity of the virtual transfer volume is increased by the equivalent of the reserved volume Ru capacity, so that additional transfer frames may be stored.

Abstract: The computer system comprises a first and second computer, at least one first storage system connected to the first computer, and a plurality of second storage systems connected to the second computer as well as being connected to the at least one first storage system. The first computer issues to the first storage system a normal write request and control-use write request stamped with issue time. A control-use write request is issued at periodic intervals. The first storage system receives a write request and transmits the write request as update-data to second storage system in such a way that the issue order is ascertainable. The second storage system receives the update-data and, responsive to a reflect instruction from the second computer, reflects the update-data in storage areas.