Abstract: A method for more effectively distributing the I/O workload in a data replication system is disclosed herein. In selected embodiments, such a method may include generating an I/O request and identifying a storage resource group associated with the I/O request. In the event the I/O request is associated with a first storage resource group, the I/O request may be directed to a first storage device and a copy of the I/O request may be mirrored from the first storage device to a second storage device. Alternatively, in the event the I/O request is associated with a second storage resource group, the I/O request may be directed to a second storage device and a copy of the I/O request may be mirrored from the second storage device to the first storage device.

Abstract: A method includes detecting that a first file and a second file are duplicates, and storing the first file and the second file to a target storage device. Metadata is written to the target storage device in association with the first file, wherein the metadata identifies the location of the second file that is a duplicate of the first file. Later, an application program requests a first read operation to read the first file. In response to a media error that results from the first read operation, the target storage device reads the metadata associated with the first file to identify the location of the second file, performs a second read operation to read the second file instead of the first file, and provides the second file to the application program in satisfaction of the requested first read operation.

Abstract: According to one embodiment, a video server includes an allocator. The allocator allocates resources for performing rebuilding. When processing which needs to be performed in real time is requested during the rebuilding, the allocator determines whether resources for performing the requested processing are available. When resources for performing the requested processing are available, the allocator allocates available resources to the requested processing. When resources for performing the requested processing are not available, the allocator deallocates resources allocated to the rebuilding to secure resources for performing the requested processing, and allocates the secured resources to the requested processing.

Abstract: A method of operation of a disk storage system includes: providing a disk storage controller; coupling a storage carrier, having a first physical disk and a second physical disk, to the disk storage controller; detecting a failure of the first physical disk; writing a non-volatile memory to show the second physical disk is unavailable when the storage carrier is de-coupled from the disk storage controller; and logging a first written stripe in the non-volatile memory for update when the second physical disk is not available including updating only the written stripe in the second physical disk when the storage carrier is again coupled to the disk storage controller.

Abstract: An image processing apparatus includes an image processing unit configured to perform image processing, a storage unit configured to be capable of storing an application program installed in the image processing apparatus, a first determination unit configured to determine whether the application program had ever been installed in the image processing apparatus, and a control unit configured to selectively control the image processing unit to be operable and control the image processing unit not to operate according to the determination by the first determination unit if an error has occurred in the storage unit.

Abstract: A disk array system, upon detecting a failure in any data disk from among a plurality of data disks providing one or more RAID groups, conducting a correction copy to any spare disk, using one or more other data disks belonging to the same RAID group as the data disk causing the failure. When the data disk causing the failure has been replaced with a new data disk, the disk array system alters the management so that the data disk can be managed as a spare disk, and the spare disk can be managed as a data disk.

Abstract: An memory device including a data region storing a main data, a first index region storing a count data, and a second index region storing an inverted count data, where the data region, the first index region, and the second index region are included in one logical address.

Abstract: Out-of-order reconstruction of a RAID storage device at a replacement storage device enables the replacement storage device to execute I/O for reconstructed regions during reconstruction of the replacement storage device. In one embodiment, the failed storage device is analyzed to find recoverable information, which is copied to the replacement storage device to reduce the need for reconstruction. In another embodiment, the priority for region's reconstruction is increased upon detection of an I/O to the region. The I/O is queued until reconstruction of the region and then executed after reconstruction of that region so that I/O at the region need not be repeated during reconstruction of the remainder of the replacement storage device.

Abstract: An information system including: a first and second storage apparatus including a first and second volume; a failure detection storage apparatus including a third volume; wherein, for backup purposes, the first and second volumes form a remote copy pair, and, for I/O request purposes, are recognized as a single volume labeled with a same volume identifier, but accessible by alternative access paths designated with differing priorities; wherein, if one apparatus detects a failure in the other or a connection failure, the apparatus detecting the failure stores, in the third volume, a failure information flag showing failure; wherein, upon receiving the I/O request through the second access path, the second storage apparatus determines whether the failure information flag is stored in the third volume, and sends an error reply of the I/O request to the host computer if the failure information flag is stored in the third volume.

Abstract: A management system, which manages a host computer and a storage system, holds cluster information, specifies an active-state host computer and an inactive-state host computer based on a backup instruction specifying a virtual host identifier, determines the need for executing a replication for disaster recovery use, and when necessary, executes this replication for disaster recovery use in combination with a replication for backup use.

Abstract: According to one embodiment, an information processing apparatus includes a board having an expansion slot, a RAID controller card inserted into the expansion slot, and a processor mounted on the board. The RAID controller card comprises a RAID controller configured to execute a write control and a read control in a first mode, the write control includes dispersing data, writing the dispersed data in first storage devices, calculating a parity of the dispersed data written in the storage devices, and writing the calculated parity in a second storage device, and the read control includes reading the dispersed data written in the first storage devices. The processor and is configured to execute the write control and the read control in a second mode, wherein the processor is configured to executes transfer of the dispersed data to the first storage devices and the second storage device via the RAID controller card.

Abstract: A disk controller for controlling disk devices for storing redundant data distributed thereacross, the disk devices providing a logical volume, the disk devices including pool volumes allocatable to one of the logical volume. The disk controller includes a memory for storing information indicating a relationship between the pool volumes and the logical volume; and a processor for performing data reconstruction in accordance with a failure of the disk devices, a process of the data reconstruction, the processor being configured to detect an error in a part of the pool volumes included in the other disk devices when reading data from the pool volumes included in the other disk devices, determine whether the detected pool volume is allocated to the logical volume in reference to the information, and initialize the part of the detected pool volume when the detected pool volume is unallocated to the logical volume.

Abstract: Various embodiments of the present invention provide systems and methods for data regeneration. For example, a system for regenerating data is disclosed. The system includes a media defect detector that is operable to identify a potential media defect associated with a medium from which an input signal is derived, an attenuation amplitude detector that generates an attenuation factor, and a data detector. The data detector includes a first data path and a second data path. The first data path includes a bank of two or more selectable noise prediction filters and the second data path includes a fixed noise prediction filter and the attenuation factor. The data detector processes a derivative of the input signal using the second data path when the potential media defect is indicated, and processes the derivative of the input signal using the first data path when a media defect is not indicated.

Abstract: Provided are a method, system, and article of manufacture for using virtual copies in a failover and failback environment. Updates are copied from a primary first storage at the primary site to a secondary first storage at the secondary site during system operations. A second storage is maintained at least one of the primary and secondary sites. A failover is performed from the primary site to the secondary site after a failure at the primary site. The at least one second storage is used after recovery of the primary site to synchronize the secondary site to the primary site. Only updates made to the secondary site during the failover are copied to or from the at least one second storage in response to the recovery at the primary site.

Abstract: The present invention provides a system and a method for utilizing a parity protection module to back up data on striped aggregates. Specifically, the system computes party data for data stored at a particular location of each of a plurality of constituent aggregates, and stores the parity on one of the constituent aggregates that is a parity owner for that particular location of data. In the event one of the constituent aggregates fails, new data may still be accessed by the system (the striped aggregates), both to write new data, and to read data stored on the failed aggregate. In particular, the parity protection module allows clients to read data from a failed aggregate by running a reverse parity computation, which may also be used to restore the data to the failed aggregate.

Abstract: Realigning storage devices arranged as storage arrays when one of the storage arrays enters a critical state after failure of a storage device is disclosed. The method is particularly useful for RAID groups of storage devices. The method may be used with hard disk drives, solid-state drives, and other storage devices arranged as groups. The method includes identifying when a storage array of a plurality of storage arrays is in a critical condition. A critical condition storage array and a healthy storage array are identified. Both the critical condition storage array and the healthy storage array are rebuilt. The rebuilding includes configuring the critical condition storage array to include a storage device from the healthy storage array and configuring the healthy storage array to function with one less storage device. The method may be implemented in hardware, firmware, software, or a combination thereof.

Abstract: A RAID-group converting apparatus converts two RAID groups into one RAID group. The RAID-group converting apparatus includes: a data-reading unit that reads at least non-parity data from data including the non-parity data and parity data, for each stripe from a plurality of recording media belonging to the two RAID groups; a parity-generating unit that generates two parities using the data belonging to a same stripe read by the data-reading unit; and a parity-writing unit that writes the two parities generated by the parity-generating unit into a parity storage area belonging to the same stripe.

Abstract: This storage system includes a first storage sub system having a first logical volume where a first data area is dynamically allocated to each prescribed area, and which stores data transmitted from a host computer in the first data area, and a second storage sub system having a second data area for backing up the first logical volume; wherein the first storage sub system includes: a first management unit for managing the status of the first data area allocated to each of the areas of the first logical volume; a transfer unit for transferring the data stored in the first data area allocated to each of the areas of the first logical volume to the second storage sub system; and a restoration unit for restoring the first logical volume based on the status of the first data area managed by the first management unit and/or the data transferred from the second storage sub system.

Abstract: The storage control device of the present invention is able to perform input and output of data between blocks whose size is different with good efficiency. The size of extended logical blocks, which are units of data input and output within a storage control device, and the size of physical blocks, which are provided within the storage device, are different from one another. A write object range generation unit reads out both of the extended logical blocks which are adjacent to the write data, and creates a write object range by linking them to the write data. An assurance code checking unit checks a corresponding assurance code for each of these extended logical blocks. And a block size adjustment unit deletes superfluous data from the adjacent blocks, and adjusts the size of the write object range, so that it becomes an integral multiple of the size of the physical blocks.

Abstract: Exemplary embodiments of the present invention comprise a method for the use of an intra-disk redundancy storage protection operation for the scrubbing of a disk. The method comprises initiating a disk scrubbing operation upon each disk of a plurality of disks that are comprised within a storage disk array, issuing a disk scrubbing command for a predetermined segment of the disks that are comprised within the storage disk array at a predetermined time interval, and identifying an unrecoverable segment on a disk. The method further comprises determining if unrecoverable sectors comprised within the unrecoverable segment can be reconstructed, and reconstructing the unrecoverable sectors of the unrecoverable segment and relocating the segment to a spare storage location on the disk in the event that the segment cannot be reconstructed within its original storage location.

Abstract: A fast rebuild mechanism that includes a background initialization mechanism. The fast rebuild mechanism allows a RAID controller to be made aware of what blocks are actually in use so that only those blocks are rebuilt after a disk drive failure. The fast rebuild mechanism also includes functionality for an IO controller (such as storage controller) to detect whether a block has stored data to indicate that the block has valid data when the block is accessed.

Abstract: Provided are a method, system, and article of manufacture for using virtual copies in a failover and failback environment. Updates are copied from a primary first storage at the primary site to a secondary first storage at the secondary site during system operations. A second storage is maintained at at least one of the primary and secondary sites. A failover is performed from the primary site to the secondary site after a failure at the primary site. The at least one second storage is used after recovery of the primary site to synchronize the secondary site to the primary site. Only updates made to the secondary site during the failover are copied to or from the at least one second storage in response to the recovery at the primary site.

Abstract: A signal bearing medium tangibly embodying a program of machine-readable instructions executable by a processor to perform operations to read information stored in a storage system. The storage system includes a controller coupled to a plurality of type I performance class disk drives and at least one type II performance class backup disk drive. The operations include executing a first read request for a first set of information from a first type I performance class disk drive and executing a second read request for the first set of information from a first type II performance class backup disk drive in response to an occurrence of a first read error associated with the execution of the first read request.

Abstract: An error correction code system for a memory for improving performance and testability. The parity columns of the memory array can be positioned centrally within the array to minimize routing distance to ECC logic circuitry. The parity columns can be grouped together or distributed throughout the array to optimize performance. A multiplexor circuit can be included for selectively coupling only the parity bits stored in the parity memory array to I/O circuitry. Therefore, the parity columns can be directly tested, and testing of the ECC logic circuitry is facilitated.