Abstract: In a storage system, a first loop and a second loop are connected to a controller, and at least one of the first loop and the second loop is connected to existing storage devices (which are physical storage devices other than additional storage devices, which are physical storage devices which are additionally provided). In processing for additional provision, after having disconnected all of the existing storage devices from the first loop, the controller connects an additional storage device to the first loop. And the controller acquires, via said first loop, an address acquired by this additional storage device, and makes a first suitability decision as to whether or not this address is appropriate. And, if the result of this first suitability decision is negative, then the controller blocks up this additional storage device whose address has been acquired.

Abstract: A SAN manager acquires configuration information from devices constituting a SAN and produces a corresponding relationship between a host computer and a virtual volume (virtual volume mapping) and a corresponding relationship between the host computer and a real volume (real volume mapping). Based on those pieces of mapping information, the SAN manager outputs a corresponding relationship between virtual and real volumes. Meanwhile, the failure notification messages received from the in-SAN devices are construed to detect and output an influence of the failure upon the access to a real or virtual volume. Furthermore, when receiving a plurality of failure notifications from the devices connected to the SAN, the plurality of failure notifications are outputted with an association based on the corresponding relationship between real and virtual volumes.

Abstract: A storage system including: a controller; and, a plurality of physical storage devices coupled to the controller and constituting a RAID group; wherein the controller provides one or more logical volumes belonging to the RAID group, each of the one or more logical volumes having a plurality of storage areas; one or more virtual volumes, wherein, when receiving a write request to a virtual volume of the one or more virtual volumes, the controller allocates a storage area in a logical volume to the virtual volume; and writes data to the allocated storage area, wherein, when a physical storage device of the plurality of physical storage devices fails, the controller selectively performs a RAID restore process to a storage area allocated to a virtual volume.

Abstract: The present disclosure includes methods and devices for stripe-based memory operation. One method embodiment includes writing data in a first stripe across a storage volume of a plurality of memory devices. A portion of the first stripe is updated by writing updated data in a portion of a second stripe across the storage volume of the plurality of memory devices. The portion of the first stripe is invalidated. The invalid portion of the first stripe and a remainder of the first stripe are maintained until the first stripe is reclaimed. Other methods and devices are also disclosed.

Abstract: The method begins with a processing module determining whether to reconstruct data corresponding to a plurality of data slices when the plurality of data slices is to be transferred from a first type of memory device to a second type of memory device. The method continues with the processing module retrieving the plurality of data slices from a first set of memory devices that are of the first type of memory, reconstructing at least a portion of the data from the plurality of data slice in accordance with a first error coding dispersal function to produce reconstructed data, encoding the reconstructed data in accordance with a second error coding dispersal function to produce a second plurality of data slices, and storing the second plurality of data slices in a second set of memory devices that are of the second type of memory when the data is to be reconstructed.

Abstract: A complementary error evaluator polynomial is generated by obtaining a syndrome polynomial and one or more erasure locations. The syndrome polynomial and the erasure locations are associated with Reed-Solomon encoded information. A complementary error evaluator polynomial and an error locator polynomial are simultaneously generated using the syndrome polynomial and the erasure locations where the complementary error evaluator polynomial is a complement of the error evaluator polynomial.

Abstract: A data modulation method and a data error correction method are provided. The data modulation method includes generating a channel sequence for an input sequence, determining whether or not the channel sequence violates a Run Length Limit (RLL) constraint, and performing, when the channel sequence violates the RLL constraint, bit flip at a position prior to a position at which the RLL constraint is violated among positions of bits included in the channel sequence. The data error correction method includes detecting an error bit of received data using a parity check matrix, determining whether or not the error bit is an error caused by bit flip, and correcting the error bit when the error bit is an error caused by bit flip for applying an RLL constraint.

Abstract: A dispersed storage network includes a dispersed storage device to store data. The dispersed storage device includes a processing module operable to slice a data segment of a data object into data slices, in which the number of data slices corresponds to a number of pillars for storing the data object. The processing module further creates a slice name for each of the data slices. The slice name includes routing information containing a vault identifier that identifies at least one user of the data object and a slice index based on the vault identifier and a pillar identifier that identifies a pillar associated with the data slice. In addition, the slice name includes a source data name containing an identifier of the data object.

Abstract: A method for testing hard disks under an extensible firmware interface (EFI) provides a device tree of hard disks. Nodes of the device tree represent block devices or file systems of the hard disks. Devices paths and handles corresponding to each of the device paths are obtained from the device tree. Parent controller handles of each of the device paths are obtained. If there are parent controller handles the same as the obtained handles, the parent controller handles the same as the obtained handles are deleted. The computer determines that a number of the hard disks is equal to a number of the device paths corresponding to the remained parent controller handles. Nodes information of each of the device paths corresponding to the remained parent controller handles are determined as hard disk information of each of the hard disks.

Abstract: An apparatus according to the present invention is designed to perform formatting processing on an information storage medium. The storage medium has a data storage area including a user data area and a spare area. The user data area is provided to write user data on, while the spare area includes a replacement block to be used as a replacement for a block that has been detected as a defective block. The replacement block stores instruction information that instructs to read data from the defective block when data is read from the replacement block. The apparatus includes a control section for controlling the formatting processing. In performing the formatting processing, the control section updates information stored in the replacement block such that when data is read from the replacement block, the data is not read from the defective block.

Abstract: A hard disk drive with a disk that has a plurality of data bits. The drive includes a circuit that reads each data bit n times and selects a value for the bit based on a reliability factor. The circuit may select a bit based at least in part on the most frequent occurrence of one of a plurality of values. For example, if more 0s occurred than 1s the bit would be set to 0. The reliability factor may be a ratio of the occurrence of 0s to the occurrence of 1s. A bit can be not selected or deselected if the reliability factor exceeds a threshold value.

Abstract: A storage device is for restoring the data saved in a nonvolatile memory to a cache memory, even if there is not a read response from the nonvolatile memory. In a data saving operation, parity data of to-be-saved data is generated, and the to-be-saved data and the parity data having CRCs and AIDs added thereto are written into a flash memory. In a data restoring operation, if an operation to read data from the flash memory is not completed within a predetermined period of time, the data reading operation is suspended, and additional data is set. The to-be-saved data having a data error corrected with the parity data is then written into the cache memory.

Abstract: A backup method makes a backup of cache data to a nonvolatile memory by using a controller, the cache data being stored in the volatile memory. The backup method includes writing the cache data stored in the volatility memory in a selected area of the nonvolatile memory, generating party data by operating the parity operations between each of the predetermined parts of the cache data in the volatile memory, verifying whether an error found in the part of the cache data in the nonvolatile memory can be recovered by using the parity data, and rewriting the part of the cache data when the error found in the part of the cache data in the nonvolatile memory cannot be recovered by using the parity data in an area of the nonvolatile memory different from the selected area.

Abstract: Availability of an information system including a storage apparatus and a computer is improved. First and second storage apparatuses execute remote copy of copying data written into a first primary volume from the computer to a second primary volume, at least one of the first and second storage apparatuses executes local copy of copying the data written into the first or second primary volume in a self-storage apparatus to the corresponding first or second secondary volume, and the computer switches the destination of a write request of the data from the first storage apparatus to the second storage apparatus in case of a failure occurring in the first storage apparatus.

Abstract: A controlling apparatus for controlling a disk array unit includes a cache memory for caching data of the disk array unit; a nonvolatile memory for storing the data in the cache memory; and a control unit for detecting a defective location in the nonvolatile memory where the data is stored defectively and updating information indicating the defection location, for generating an error detection code of the updated information, for writing the generated information and the associated error detection code into an area of the nonvolatile memory different from any area where any information indicating any defective location previously detected and stored into the nonvolatile memory, and for controlling writing the data in the cache memory into a location of the nonvolatile memory designated by any selected one of the information stored in the nonvolatile memory.

Abstract: If data is lost a possibly logically bad pattern is placed in a standard size data block in a storage device, and the Logical Block Address associated with the data block is inserted in a Bad Block Table. The possibly logically bad pattern is able to be detected, and the Bad Block Table is checked to determine if the data block to be read is in fact Logically Bad. A data check response may be given to a host if a Logical Block Address associated with the standard size data block is present in a Bad Block Table. The possibly logically bad pattern may have a first predefined data portion and a second predefined data portion and may be repeated the requisite number of instances to fill the standard size data block.

Abstract: Provided is a disk array device which enables the amount of use of a physical disk to be reduced as much as possible even when there exist a plurality of logic extents of the same data. A disk array device which assigns, to a physical extent of a physical disk, a logic extent of a logic disk to which a host device makes an access, which device includes a data checking unit 14 which, at the time of assignment of the logic extent to the physical extent, checks identity of data of the logic extent and data of the physical extent already assigned, and an extent control unit 11 which, when a physical extent of the same data exists, assigns a plurality of the logic extents to the physical extent in question in overlap to manage assignment.

Abstract: A storage system includes data storage devices, spare storage devices used when a failure occurs in a data storage devices, a group management unit that divides the data storage devices into groups and implements a redundancy, a data storage device restoration unit that assigns the spare storage device as a replacement when a failure occurs, and a configuration change unit changing configuration of the group to which the data storage devices belong. The configuration change unit includes, a spare storage device securing unit that secures the spare storage device, a change processor that writes data concerning the group into the spare storage device, and a change restoration unit that performs continuation of the configuration change, or restoration of the group to a state in a start, using the data written into the spare storage device when the configuration change of the group is interrupted.

Abstract: A parity-data generating unit generates, in response to a write request containing update data, updated parity data in the parity group to which the update data belongs. A time-series-information generating unit generates time-series information indicating an anteroposterior relationship during writing between the update data and existing data stored in the unit storage area to which the update data is to be written. A time-series-information adding unit adds the time-series information, generated in response to the write request, to the update data as certification time-series information and that adds comparison time-series information to the updated parity data in association with the update data, the comparison time-series information having the same value as the certification time-series information.

Abstract: A RAID testing method and a RAID testing system including a reading unit, an option-ROM, a recording unit and several RAID configuration data are provided. These data are either contained in several binary files or stored in a memory. In the method, first, these data are read by the reading unit under a first mode to simulate connecting to several physical disk drives in a first manner. Then, a global RAID configuration information is generated according to these RAID configuration data. Further, these data are read by the reading unit under a second mode to simulate connecting to these physical disk drives in a second manner. Afterwards the global RAID configuration information is updated by the option-ROM in accordance with the second mode. Moreover, the global RAID configuration information is recorded by the recording unit.

Abstract: A method of storing data in a data storage device including a hard disk drive (HDD) and a non-volatile memory (NVM) includes analyzing an access command to access the NVM and transmitting data included in the access command to the HDD based on the analysis result.

Abstract: Hard discs constituting a disc array system are arranged at locations far from one another so as to eliminate their simultaneous damage due to a local disaster and concentration of the processing load thereby suppressing the recovery time upon hard disc failure. It is possible to realize continuous operation without system down even when the other disasters have occurred. A plurality of hard disc devices are arranged at different locations far from one another, write-in data from a server device is mapped by the RAID method, and a data packet added by the RAID information and the error correction code is distributed to the respective hard discs. Moreover, the line connection device for performing data transfer to the hard disc device has the RAID control function while the main control device is dedicated to monitoring of the hard disc devices and data recovery process upon occurrence of a failure.

Abstract: A system and method are provided for automating full stripe operations in a redundant data storage array. In a redundant storage device controller, a parity product is accumulated that is associated with an information stripe. The parity product is stored in controller memory in a single write operation. A stored parity product is then written in a storage device. The parity product may be accumulated in a RAID controller, stored in a RAID controller memory, and written in a RAID. For example, the controller may receive n data stripelets for storage. The parity product is accumulated by creating m parity stripelets, and the m parity stripelets are written into the controller memory in a single write operation. Alternately, the controller may receive (n+m?x) stripelets from a RAID with (n+m) drives, recover x stripelets, and write x stripelets into controller memory in a single write operation.

Abstract: A multiple channel storage device may include a host controller to receive input data from a host device and a buffer memory to store the input data and associated error correcting data prior to downstream storage. Multiple storage channels downstream from the buffer memory may store the input data and associated error correcting data in at least one of the storage channels on a non-volatile storage media. An error correcting engine between the host controller and the buffer memory may perform error correction encoding on the input data from the host device to generate the associated error correcting data for storage in the buffer memory. Such error correcting engine may protect against data errors in the buffer memory and in the storage channels.

Abstract: A disk array apparatus where, when a failure occurs at a part of a cache memory, a memory area of an I/O processing controller other than the memory area where the failure has occurred is utilized without taking over the whole I/O processing to an I/O processing controller of other system is provided, so that influence of performance degradation can be minimized. In a disk array apparatus including dual cache memories, when a failure occurs at a part of the cache memory, only a memory area where the failure has occurred is closed, and reallocation thereof to another memory area of the same cache memory is conducted to continue an I/O processing.

Abstract: An error determining apparatus includes an Error Detection Code (EDC) error detector to detect an EDC error of data read from an optical disk, a continuity error detector to detect a continuity error of a currently decoded address by comparing the currently decoded address and a previously decoded address, and an error determiner to receive information on the previously determined error state and to determine a final error state of the currently decoded address of the optical disk based on the EDC error detected by the EDC error detector, the continuity error detected by the continuity error detector, and the previously determined error state.

Abstract: Techniques are provided for locating data. Mapping information for blocks associated with a file is provided. It is determined that a copy service has copied source blocks to target blocks. It is determined whether the mapping information should be updated to refer to the target blocks. Then, updated mapping information is provided in response to determining that the mapping information should be updated to refer to the target blocks.

Abstract: Iterative code system for streaming hard disk drives (HDDs). A novel approach is presented by which any of a wide variety of error correcting codes can be applied within devices that include or interface to HDDs or other memory storage devices that provide streaming information. A means is provided by which at least two separate clock domains are employed such that the streaming information can be provided at a first rate according to a first clock domain, and the decoding processing of the streaming information can be provided at a second rate according to a second clock domain. Using this approach, a wide variety of error correcting codes can employed, including those whose decoding processing would not be possible if required to operate at the typically high rates at which streaming information is oftentimes provided from HDDs or other memory storage devices.

Abstract: According to one embodiment, an information recording apparatus includes a disk recording medium, a nonvolatile memory provided with a plurality of memory blocks including a plurality of alternate blocks, a data write section which writes data to a memory block of an address assigned by the system, a data read section which reads the data from the memory block of the write-assigned address, a judgment section which determines whether or not the data read by the data read section is correctly written, and a control section which determines whether or not an unused alternate block is present by referring to the management information of the alternate blocks used in place of the memory blocks, when it is determined that the data is not correctly written, and notifying the system that data cannot be written to the write-assigned address, when it is determined that an unused alternate block is not present.