Abstract: A computer system which has a plurality of computers and a storage device subsystem connected to the plurality of computers. The storage device subsystem has a plurality of storage devices and a plurality of interfaces, through which the subsystem is connected to the computers. One of the plurality of computers has a management means for holding therein data indicative of the storage devices and a connection relationship between the computers and storage device subsystem. Each computer, when wanting a new device, informs the management means of its capacity and type. The management means receives its notification and selects one of the storage devices which satisfies the request. And the management means instructs the storage device subsystem to set predetermined data in such a manner that the computer can access the selected device.

Abstract: A storage system conducting remote copy functions such that, when data is updated at a local site, contents of the update can be referred to in real time by storage at a remote site. A disk-control unit at a remote site receives file data written in accordance with an update of a file in a storage system at a local site and a history of the file-management information from the storage system at the local site and stores the data and the history. A file-system processing unit refers to the history and updates the file-management information in a file-system cache in accordance with the update of the file in the storage system at the local site. When a client issues a read request, the file-system processing unit refers to the file-management information updated in the file-system cache and transfers the contents of the update of the file to the client.

Abstract: A volume provider unit in a computer system that detects a logical block address of a read or write I/O accessing a logical volume of a storage device from a host. According to the logical block address fetched, a storage domain of the logical volume is dynamically expanded. Moreover, the storage domain of the logical volume is reduced or expanded according to an instruction of logical volume capacity reduction or expansion from a host commander part to a volume server.

Abstract: Interfaces of SAN and NAS, prevents data miss even when a trouble occurs and makes it possible that an arbitrary number of NAS interfaces access the same file system with high performance. A storage system includes multiple interfaces for external connection, multiple disks accessed from multiple interfaces, and a shared memory accessed from multiple interfaces. The multiple interfaces are block interfaces executing disk block I/O request, and file interfaces of file servers executing file I/O request. A file system in the file servers is constructed in a part of the disks, and a log storage area holding change log of the file system, and a management file server information storage area holding information of managing file server performing exclusive access control of file system and management of log storage area are formed in the shared memory.

Abstract: A system for performing efficient backup in an environment where a plurality of file servers exist, making the plurality of file servers externally look like a single apparatus. The present invention provides a computer system comprising hosts, first and second file servers connected to the hosts, and a storage system connected to the first and second file servers. The second file server determines that a file as a backup object is managed by the first file server, and notifies the first file server of an instruction of backup. In response to this instruction, the first server sends the second file server an identifier of a storage device that stores duplicate data of the file in question. Based on the received identifier, the second file server sets a path to that storage device, and obtains the backup data from that storage device.

Abstract: A storage device system comprises interfaces connected to computers, a plurality of magnetic disks, and a control device that controls the plurality of magnetic disks. When a command from one of the computers instructing a tape library device to load a magnetic tape into a tape device is received by one of the interfaces, the control device selects a storage region that is managed as a virtual tape from among storage regions of the magnetic disks. When one of the interfaces receives an access request from the computer to the tape device, the control device controls to access the storage region selected.

Abstract: A storage has NAS and SAN functions and a high degree of freedom to configure a system to reduce the management and operation cost. The storage includes a plurality of interface slots in which a plurality of interface controllers can be installed, a block I/O interface controller which has SAN functions and which can be installed in the slot, a file I/O interface controller which has NAS functions and which can be installed in the slots, a storage capacity pool including a plurality of disk devices accessible from the interface controllers, and a storage capacity pool controller to control the storage capacity pool.

Abstract: A computer system which has a plurality of computers and a storage device subsystem connected to the plurality of computers. The storage device subsystem has a plurality of storage devices and a plurality of interfaces, through which the subsystem is connected to the computers. One of the plurality of computers has a management means for holding therein data indicative of the storage devices and a connection relationship between the computers and storage device subsystem. Each computer, when wanting a new device, informs the management means of its capacity and type. The management means receives its notification and selects one of the storage devices which satisfies the request. And the management means instructs the storage device subsystem to set predetermined data in such a manner that the computer can access the selected device.

Abstract: The invention provides both interfaces of SAN and NAS, prevents data miss even when a trouble occurs and makes it possible that an arbitrary number of NAS interfaces access the same file system with high performance. A storage system includes multiple interfaces for external connection, multiple disks accessed from multiple interfaces, and a shared memory accessed from multiple interfaces. The multiple interfaces are block interfaces executing disk block I/O request, and file interfaces of file servers executing file I/O request. A file system in the file servers is constructed in a part of the disks, and a log storage area holding change log of the file system, and a management file server information storage area holding information of managing file server performing exclusive access control of file system and management of log storage area are formed in the shared memory.

Abstract: A volume provider unit in a computer system that detects a logical block address of a read or write I/O accessing a logical volume of a storage device from a host. According to the logical block address fetched, a storage domain of the logical volume is dynamically expanded. Moreover, the storage domain of the logical volume is reduced or expanded according to an instruction of logical volume capacity reduction or expansion from a host commander part to a volume server.

Abstract: In a storage area network (SAN), when a host accesses a storage system, the host is certified to restrict any unauthorized access. The storage system includes an access setting section and a certifying section to restrict accesses from respective hosts. When a host accesses data on a disk, the host issues an inquiry to a file server program of a host to receive information of a physical location of a file containing the data on the disk. The host accesses the disk according to the information. Simultaneously, the file server program allows, by a disk management program, the access to the area specified by the access request from the host.

Abstract: An object of the present invention is to permit, with account movement, increase of the speed of data transfer of an exclusive storage area of a targeted account (a home directory of a user) and reduction of the load of a controller of a host computer.

Abstract: A storage has NAS and SAN functions and a high degree of freedom to configure a system to reduce the management and operation cost. The storage includes a plurality of interface slots in which a plurality of interface controllers can be installed, a block I/O interface controller which has SAN functions and which can be installed in the slot, a file I/O interface controller which has NAS functions and which can be installed in the slots, a storage capacity pool including a plurality of disk devices accessible from the interface controllers, and a storage capacity pool controller to control the storage capacity pool.

Abstract: A volume provider unit in a computer system that detects a logical block address of a read or write I/O accessing a logical volume of a storage device from a host. According to the logical block address fetched, a storage domain of the logical volume is dynamically expanded. Moreover, the storage domain of the logical volume is reduced or expanded according to an instruction of logical volume capacity reduction or expansion from a host commander part to a volume server.

Abstract: A volume provider unit in a computer system detects a logical block address of a read or write I/O accessing a logical volume of a storage device from a host. According to the logical block address fetched, a storage domain of the logical volume is dynamically expanded. Moreover, the storage domain of the logical volume is reduced or expanded according to an instruction of a logical volume capacity reduction or expansion from a host commander part to a volume server.

Abstract: A method for backing up the data of a disk array system having network file server and storage area network functions easily and rapidly without using a route for data to be not backed up. Upon receipt of a backup request, a network file server module copies files on the disk array system's regular volumes to a backup volume. The network file server module then requests a storage area network module to copy the files to an external storage device. Finally, the storage area network module copies the current contents of the backup volume to the external storage device. The network file server module can limit the data to be backed up, thereby reducing the backup time requirements. The load on a LAN does not increase because the storage area network module acquires the data to be backed up. The processing speed increases thanks to backup load distribution within the disk array system.

Abstract: It is an object of the present invention to allow storage devices to be used selectively according to the characteristics of each storage device in a computer system where different kinds of storage devices coexist.

Abstract: A method of generating and linking programs required in a data linkage system to link data among a plurality of computer systems, for example a mainframe and an open system, is provided. In the data linkage system with a means for data transfer via a storage device, a program generation tool is prepared in the open system. The program generation tool reads a data stream definition and generates an intermediate file area securing program and a data linkage program A, both run on the mainframe, and a data linkage program B run on the open system. These programs are linked with one another. The intermediate file area securing program and the data linkage program A are transferred to the mainframe where they are executed.

Abstract: A network attached storage (NAS) system includes a disk array unit equipped with a copy device that copies data, and a NAS processing unit that provides file service via a network and is connected via a communication path to the disk array unit. The NAS processing unit is equipped with a snapshot management device that manages snapshots. The snapshot management device of the NAS processing unit designates a physical block to be copied as a snapshot. The copy device on the disk array unit copies the designated physical block within the disk array unit to create a snapshot and stores the snapshot in a separated region. The snapshot management device of the NAS processing unit manages meta data of the snapshot data in a manner accessible by the user depending on requirements.

Abstract: A computer system in which a host computer is connected to a storage unit, the storage unit operating in a unit of a file. A file attribute control unit and the storage unit execute the processing being linked together so that, in response to a request from a client computer, the host computer executes a file attribute control program to add a particular attribute to the file, and that the storage unit operates in response to the attribute that is added.