Abstract: In order to manage the various types of attribute information within the storage-device system, the storage-device system includes the following databases within a file-access controlling memory: a database for managing index information for managing contents of the files, and an index retrieval program, a database for managing the attribute information on the files, and a database for managing storage positions of blocks configuring a file. When the storage-device system receives an access request to a file, the utilization of these databases allows the storage-device system to make the access to the access-target file.

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: In a distributed file system, when a user requests a computer to create a distributed file, a management computer acquires a list of computers complying with an allocation rule selected by the user from allocation rules taking the performance, security level, reliability level and utility rate into consideration. When the user requests the computer to access the distributed file, on the other hand, the partial files and the server information are collected from each computer. Each computer evaluates the allocation of the partial files based on the selected allocation rule and the server information from each computer, and if required, selects a destination computer and instructs the partial files to be moved to the destination computer.

Abstract: A storage device is provided with a file I/O interface control device and a plurality of disk pools. The file I/O interface control device sets one of a plurality of storage hierarchies defining storage classes, respectively, for each of LUs within the disk pools, thereby forming a file system in each of the LUs. The file I/O interface control device migrates at least one of the files from one of the LUs to another one of the LUs of an optimal storage class, based on static properties and dynamic properties of each file.

Abstract: To solve a problem of waste of management resources/wasteful management involved in the setting of information defining access rights of multiple users to a single file and the setting of differing file attributes information for each file, this system has a file attributes DB operating as a database managing file attributes, a accounting information DB as a database managing accounting information and a local file system storing file data. The accounting information DB holds records for each combination of a user or group and a server and adds records for each additional user or server.

Abstract: Snapshots are implemented by combining original data in a place where an operational volume has been updated with data in a place where the operational volume has not been updated. A snapshot management table maintains a value indicating that update has not been conducted, or a storage place of original data, for each of combinations of blocks in the operational volume and the snapshots. If there is a snapshot in which update has not been conducted in a update place at the time of update, then original data is copied and the snapshot management table is updated. The copied original data is managed by a difference block management table, which has a value indicating whether respective snapshots are referencing the data. If a snapshot is deleted, then the value indicating that the snapshot is referencing is altered in all entries in the difference block management table.

Abstract: A file server has plural NAS nodes having three processors dispersed in function, a shared cache memory shared between the plural NAS nodes and backed up by a battery, and plural storage devices. A log area for storing data with respect to an access request received by each NAS node is arranged in the shared cache memory. A network processor stores the data with respect to the access request to the log area, and transfers the data of the memory by a DMA at a reading time. Even when a failure is happened in a certain NAS node, another NAS node restores a file system using the log and continues processing to store the data with respect to the access request to the shared cache memory.

Abstract: A problem with a journaling file system is that the load on input/output processing executed between a server and a storage system is increased because a journal log is written when the file system is updated and updated data is written when flush processing is executed. In a system according to the present invention, a storage system that has received journal logs from a server uses updated data included in the journal logs to execute flush processing.

Abstract: In the storage-based snapshot creation, a block-selection specifying unit provided on a NAS processing unit specifies a block, which becomes necessary for the generation of snapshot data, to a specified-block analyzing unit within a disk apparatus. Moreover, a disk controller generates the snapshot data on the block specified as the snapshot target, while making an inquiry to the specified-block analyzing unit. This makes it possible to create the snapshot in a storage-capacity reduced manner, and to specify the snapshot creation in a partition, file, or directory unit.

Abstract: The present invention provides a file system capable of reducing time taken to switch I/O paths, and hiding the process of switching the I/O paths from the user.

Abstract: A storage medium for a file input/output control system having a plurality of first computers each having a plurality of disks and connected to a network and at least one second computer connected to the network for accessing the disks connected to the first computers. The storage medium includes a data code section storing a step of retrieving a plurality of first data access requests issued from a plurality of processes of an application and comparing the first data access requests with correspondence relation defining information to confirm that the first data access requests are accesses to the disks, a data code section storing a step of creating a plurality of second data access requests to the disks from the first data access requests confirmed to be accesses to the disks and transmitting the second data access requests to the network, and a data code section storing a step of, in each first computer, rearranging the second data access requests for each disk in the order of block numbers in each disk.

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.

Abstract: An illustrative embodiment of the present invention disclosed herein includes a file server having a file management table to obtain a logical disk ID for accessing files. A logical disk management table is consulted to obtain an I/O path corresponding to the logical disk ID, thus accessing the physical device. When a fault occurs along an I/O path, the appropriate tables are altered accordingly to reflect a new I/O path.

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 recording element or a reproducing element in a head generates heat that decomposes lubricating agent adhered to a slider surface near the recording/reproducing element of the head. This decomposed lubricating agent leads to corrosion of the magnetic layer and the like of the magnetic disk. The lubricating agent undergoes volume expansion due to this corrosion, creating a protrusion on the magnetic disk surface to which the lubricating agent is adhered. The magnetic disk surface to which the lubricating agent is adhered comes into contact with the magnetic head, leading to friction with the protective layer, the magnetic layer, and the like. In the worst case, this can lead to secondary errors where data recorded on the magnetic layer is erased.

Abstract: A storage system comprises a primary storage system comprising a primary storage apparatus and a primary control apparatus for controlling the primary storage apparatus; and a secondary storage system comprising a secondary storage apparatus and a secondary control apparatus for controlling the secondary storage apparatus. The primary storage apparatus and the secondary storage apparatus are connected to each other via a communication line. The primary storage system sends, to the primary storage apparatus, a data-transfer instruction instructing the primary storage apparatus to transfer predetermined data stored in the primary storage apparatus to the secondary storage system. The primary storage apparatus receives the data-transfer instruction, reads out the predetermined data from the primary storage apparatus, and sends the data via the communication line to the secondary storage apparatus of the secondary storage system.

Abstract: To provide an atomic force microscopy which allows the measurement of the configuration of a surface being measured by using the phenomenon observed between the surface being measured and a probe approaching thereto at very fine distance.

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 file input/output control system has first computers each having disks and connected to a network; and at least one second computer connected to the network for accessing the disks connected to the plurality of first computers, the second computer having: a retriever for retrieving first data access requests issued from a plurality of processes of an application and comparing the first data access requests with correspondence relation defining information to thereby confirm that the first data access requests are accesses to disks, the correspondence relation defining information being entered by a user in advance and indicating a correspondence relation between the disks and each of regions in a file stored in disks of the first computers; and a scheduler for creating second data access requests to the disks from first data access requests confirmed to be accesses to disks, in accordance with the correspondence relation defining information between the disks and each of the regions in a file stored in the