Abstract: A storage management technique involves: selecting a first disk from a plurality of disks in a storage system as an anchor disk; allocating a first backup slice from the plurality of disks to a redundant array of independent disks (RAID) associated with the first disk, the first RAID including at least a slice allocated from the first disk; and if it is detected that there is an inaccessible disk in the plurality of disks, determining a backup slice for a slice of the inaccessible disk based on the allocation of the first backup slice to the first RAID, for use in data reconstruction of the inaccessible disk. This can ensure that a backup slice can always be successfully determined for slices of an inaccessible disk without introducing additional time complexity.

Abstract: A primary server and a standby server operating according as a redundant server pair are connected to a common network, and the operational state of each is monitored by a first and a second client function each of which run on a device connected to the common network. Each of the client functions operate to notify the standby server in the event that the primary server ceases to be operational. The standby server determining whether the primary server is operational based upon notification received from both of the first and second client functions.

Abstract: A method of replicating tiered data includes copying a volume from a first tiered storage array of a primary processing site to a second tiered storage array of a failover processing site, wherein the volume is tiered with a first tiered organization in both the first and second tiered storage arrays, directing from a first storage controller of the primary processing site that a second storage controller of the failover processing site stop tiering the volume on the second tiered storage array, changing the first tiered organization of the volume in the first tiered storage array to a second tiered organization, and changing the first tiered organization of the volume in the second tiered storage array to the second tiered organization.

Abstract: A fault occurs in a virtual environment that includes a base space, a first subspace, and a second subspace, each with a virtual address associated with content in auxiliary storage memory. The fault is resolved by copying the content from auxiliary storage to central storage memory and updating one or more base space dynamic address translation (DAT) tables, and not updating DAT tables of the first and second subspace. A subsequent fault at the first subspace virtual address is resolved by copying the base space DAT table information to the first subspace DAT tables and not updating the second subspace DAT tables. A fault occurring with association to the virtual address of the first subspace is resolved for the base space and the base space DAT table information is copied to the first subspace DAT tables, and the second subspace DAT tables are not updated.

Abstract: A computer-implemented method for disaster recovery of multi-tier applications may include 1) identifying a multi-tier application that is provisioned with a plurality of production clusters at a production site, 2) identifying a disaster recovery site including a plurality of recovery clusters, 3) identifying, at the disaster recovery site, a failure of the multi-tier application at the production site, and 4) initiating, from the disaster recovery site, a migration of the multi-tier application from the production site to the disaster recovery site. Various other methods, systems, and computer-readable media are also disclosed.

Abstract: For preventing data loss in storage systems, a detection is made that a storage device in a plurality of storage devices is experiencing a malfunction. The type of malfunction is determined. A SMART rebuilding technique, a normal building technique, a data migration technique, or a user data backup technique is selected to preserve the data in the storage device based on the determined type of the malfunction. The selected technique is performed on the storage device.

Abstract: A method, system and computer program product are provided for implementing hardware assisted Dynamic Random Access Memory (DRAM) repair in a computer system that supports ECC. A data register providing DRAM repair is selectively provided in one of the Dynamic Random Access Memory (DRAM), a memory controller, or a memory buffer coupled between the DRAM and the memory controller. The data register is configured to map to any address. Responsive to the configured address being detected, the reads to or the writes from the configured address are routed to the data register.

Abstract: A semiconductor memory device includes a memory cell array comprising a normal memory cell and a redundancy memory cell and configured to store data, a data compression unit configured to compress data stored in the memory cell array and generate compression information, and a repair control unit configured to control a repair operation for accessing the redundancy memory cell in response to the compression information.

Abstract: A method of managing wear leveling in a data storage device includes determining whether a reliability measurement associated with a first portion of a first nonvolatile memory die satisfies a threshold. The first nonvolatile memory die is included in a plurality of memory dies. The method includes, in response to determining that the reliability measurement associated with the first portion of the first nonvolatile memory die satisfies the threshold, transferring first data from the first portion of the first nonvolatile memory die to a second nonvolatile memory die of the plurality of memory dies.

Abstract: A plurality of data centers each having a plurality of servers. When there is a failure on a data center, the load for the failed portion of the data center is distributed over all the remaining servers locally, or remotely, based on the magnitude of the failure.

Abstract: Subject matter described pertains to apparatuses and methods for operating a memory device.

Abstract: A primary storage controller is maintained in a copy relationship with a secondary storage controller, wherein the primary and secondary storage controllers are coupled to a host that is configurable to use the secondary storage controller instead of the primary storage controller. The primary storage controller determines occurrence of at least one condition in the primary storage controller, wherein the at least one condition occurs prior to a failure of the host to perform an Input/Output (I/O) operation with respect to at least one storage volume of the primary storage controller. The primary storage controller communicates the occurrence of the at least one condition to the host, wherein in response to the communicating the host is configured to determine whether to use the secondary storage controller instead of the primary storage controller based on the occurrence of the at least one condition.

Abstract: The invention proposes a method and corresponding device for exact repair of pairs of failed storage nodes interconnected in a distributed data storage system, which method and device are particularly efficient with respect to reliability while keeping the use of resources of the distributed storage network low.

Abstract: A control device manages a plurality of storage devices so that data to be recorded is redundantly recorded in different storage devices. An error monitoring unit monitors an occurrence of an error in each of the plurality of storage devices to register information indicative of error occurrence conditions in an error information storage unit for each storage device. When the use of one of the plurality of storage devices is stopped, a rebuild controller determines a timing to perform rebuild processing based on past error occurrence conditions in the storage devices other than the one storage device of the plurality of storage devices by referring to information registered in the error information storage unit.

Abstract: A storage device includes: a determination unit to determine an operation of a storage group including a plurality of storage medium based on an access operation on a logical volume serving as an access target of the storage group; and a selection unit to select based on the operation of the storage group, when a failure of at least one of the plurality of storage medium is detected, an alternative storage medium from the at least one of the plurality of storage medium.

Abstract: A method begins by a processing module determining failure mode information for a plurality of storage modules of a maintenance-free storage container. The method continues with the processing module managing storage mapping information of data content within the plurality of storage modules based on the failure mode information and receiving a data access request. The method continues with the processing module interpreting the data access request based on the storage mapping information to identify one or more of the plurality of storage modules to produce one or more identified storage modules and generating an in-container data access request based on the data access request and the one or more identified storage modules. The method continues with the processing module sending the in-container data access request to the one or more identified storage modules.

Abstract: In a memory device, an on-die register is provided that is configured to store a row address as well as a column address of a memory cell that fails a test. Storing the row address frees testing from being limited to activating at one time only rows related to a common redundant segment. Storing the row address also guides repair using segmented redundancy. As an addition or alternative, information may be stored in an anti-fuse bank that is designed to provide access to a redundant cell but has not yet enabled access to that cell. If the information stored in the anti-fuse bank relates to the failure of the redundant cell, such information may be used to avoid repairing with that redundant cell.

Abstract: Methods, systems, and computer programs are provided for failover responses to configuration node failures in SVC clusters. An SVC cluster manages a plurality of storage devices and includes a plurality of SVCs interconnected via a network, each SVC acting as a separate node. A storage device event log is saved, with an original configuration node. An entry is made in the storage device event log each time the original configuration node receives storage device events and setting the entry to a negative value indicating a storage device event has not been handled. The entry is set to a positive value indicating the storage device event has been handled after the original configuration node notifies respective subscribed clients about those of the storage device events the original configuration node receives. A new configuration node is activated in response to configuration node failures.

Abstract: An apparatus, system, and method are disclosed for bad block remapping. A bad block identifier module identifies one or more data blocks on a solid-state storage element as bad blocks. A log update module writes at least a location of each bad block identified by the bad block identifier module into each of two or more redundant bad block logs. A bad block mapping module accesses at least one bad block log during a start-up operation to create in memory a bad block map. The bad block map includes a mapping between the bad block locations in the bad block log and a corresponding location of a replacement block for each bad block location. Data is stored in each replacement block instead of the corresponding bad block. The bad block mapping module creates the bad block map using one of a replacement block location and a bad block mapping algorithm.

Abstract: An apparatus comprising a first of a plurality of array modules and a second of a plurality of array modules. The first of the plurality of array modules may be configured to connect a first one or more of a plurality of host devices to a first one or more of a plurality of storage arrays. The first array module may comprise a primary controller and a secondary controller. The second of the plurality of array modules may be configured to connect a second one or more of the plurality of host devices to a second one or more of the plurality of storage arrays. The second array module may comprise a primary controller and a secondary controller. Control of access to the storage arrays may be transferred to the secondary controller of the first array module during a failure of the primary controller of the first array module.

Abstract: A method for operating a mirrored disk storage system, comprises a detector component operable to detect that a failure has left read stability in doubt, a determiner component for determining a repair characteristic of a pair of mirrored disks, a comparator for comparing the repair characteristic of a first of the pair with the repair characteristic of a second of the pair, and a selector for selecting one of the first or the second of the pair having a preferred repair characteristic to be used as a synchronization source disk. The preferred repair characteristic comprises the characteristic that no repair is required for the one of the first or the second of the pair, or that a least repair time is required for the one of the first or the second of the pair.

Abstract: Performance degradation caused by a failure occurring in a disk array device is suppressed. The disk array device comprises the dual structure controllers which are respectively connected to the host computer through the connection path, and a plurality of physical disks, wherein the controller comprises the failure sensing unit which senses a failure of the device, and the host interface control unit which, in a case where a failure is sensed by the failure sensing unit, when an inquire about a connection path to be preferentially used is made from the host computer, notifies the connection path connected to the other controller as a preferential path.

Abstract: A method for managing storage devices in a storage subsystem having an array of storage devices includes receiving an error message; determining that the error message indicates that at least one storage device in the array of storage devices has failed; collecting an array record comprising storage device characteristics of the failed storage device in response to determining that the error message indicates that at least one storage device has failed; collating a candidate record comprising a plurality of candidate entries; comparing storage device characteristics of the failed storage device of the array record with the storage device characteristics of each of the candidate entries; identifying a first candidate storage device having storage device characteristics that match the storage device characteristics of the failed storage device; and identifying a second candidate storage device having storage device characteristics most similar to the storage device characteristics of the failed storage device.

Abstract: In a storage apparatus a control section writes, at the time of updating at least a part of first data stored in a first storage area by at least a part of second data, the second data to a second storage area other than the first storage area. In addition, the control section determines whether or not a write error occurs. When the write error does not occur, the control section combines the first data and the second data.

Abstract: Methods and apparatuses for enhanced protection of data stored in a FLASH memory system involve a controller capable of adapting to the failure of one or more FLASH memory devices in the memory system. The controller stores data in the form of page stripes, each page stripe composed of data pages, and each data page stored in a different FLASH memory device. The controller also detects failure of a FLASH memory device in which a data page of a particular page stripe is stored, reconstructs the data page, and stores the reconstructed data page in a new page stripe, where the number of data pages in the new page stripe is less than the number of data pages in the particular page stripe, and where no page of the new page stripe is stored in a memory location within the failed FLASH memory device.

Abstract: The disclosed embodiments provide a dynamic memory device, comprising a set of dynamic memory cells and a set of replacement dynamic memory cells. The set of replacement dynamic memory cells includes data cells which contain replacement data bits for predetermined faulty cells in the set of dynamic memory cells, and address cells which contain address bits identifying the faulty cells, wherein each data cell is associated with a group of address cells that identify an associated faulty cell in the set of dynamic memory cells. The dynamic memory device also includes a remapping circuit, which remaps a faulty cell in the set of dynamic memory cells to an associated replacement cell in the set of replacement cells.

Abstract: Systems and methods for management of replicated storage. Features and aspects hereof provide management of data replication among a plurality of storage systems in a manner substantially transparent to host systems attached to the storage systems. The storage systems are coupled to one another through a replication link. One storage systems is designated the primary storage system and all others are designated secondary storage systems. A common logical volume is defined with a common logical volume device identifier used by all of the replicating storage systems of a replication group and their respective attached host systems. The primary storage system processes I/O requests directed to the logical volume by accessing its physical storage volume and forwarding the request to be replicated to all secondary storage systems over the replication link. Secondary storage systems process I/O requests by shipping them over the replication link to the primary storage system for processing.

Abstract: A data storage system including at least one memory device array including memory devices for storing data; and a storage subsystem controller for performing a method for operating the memory devices within the memory device array by relocating parity entities from a first memory device to a spare memory device replacing a failed memory device, and by storing one or more of reconstructed data entities on the first memory device.

Abstract: Systems and methods to manage memory are provided. A particular method may include storing data in a primary memory that is in communication with a processor and storing in a mirrored data in a mirrored memory. The mirrored data may be compressed, and the mirrored memory may be in communication with the processor. A failure condition associated with the data of the primary memory may be detected. In response to the detected failure condition, the mirrored data in the mirrored memory may be accessed.

Abstract: Methods, apparatus and systems pertain to performing READ, WRITE functions in a memory which is coupled to a repair controller. One such repair controller could receive a row address and a column address associated with the memory and store a first plurality of tag fields indicating a type of row/column repair to be performed for at least a portion of a row/column of memory cells, and a second plurality of tag fields to indicate a location of memory cells used to perform the row/column repair.

Abstract: A remote copy system includes a first storage system including a first storage controller arid a first data volume. The first storage controller is configured to control data access requests to the first data volume. The first storage system is configured to store write data in the first data volume upon receiving a write request from a first host associated with the first storage system and generate a journal including control data and journal data A second storage system includes a journal volume and configured to receive and store the journal generated by the first storage system in the journal volume. A third storage system includes a second data volume and configured to receive the journal from the second storage system and store the journal data of the journal to the second storage system according to information provided in the control data.

Abstract: A NAS as a main machine transmits a search packet for searching for a NAS as a new backup machine when a response from a NAS as a backup machine is not received. Each of NAS receiving the search packet transmits a device information packet to the NAS as the main machine. The device information packet includes a version number of failover function and storage capacity information. The NAS as the main machine selects a NAS as the new backup machine based on the version number and the storage capacity information included in the device information packet.

Abstract: A failover information management device manages information on a failover system including two storage processing devices to each of which a storage medium is connectable. The failover information management device stores unsuitability information from which a combination of two storage processing devices determined to be unsuitable for constituting the failover system is identifiable.

Abstract: In one embodiment, the present invention includes a method for receiving an indication of a loss of redundancy with respect to a pair of mirrored memory regions of a partially redundant memory system, determining new mirrored memory regions, and dynamically migrating information stored in the original mirrored memory regions to the new mirrored memory regions. Other embodiments are described and claimed.

Abstract: A method is provided for using bad blocks in flash memory. The method includes placing in a replacement area of the flash memory a special bad block that meets a “still usable” condition from the bad blocks of the flash memory. The method also includes receiving a use request for using the special bad block in the replacement area to store user data, writing the user data into the special bad block, and determining whether the user data is successfully written into the special bad block. Further, the method includes placing the special bad block back into the replacement area for a next use request when it is determined that the user data is not successfully written into the special bad block.

Abstract: A semiconductor memory device having a bank including a redundancy cell block and a plurality of normal cell blocks includes a plurality of normal data inputting/outputting units configured to respectively input/output data from the normal cell blocks in response to a first input/output strobe signal, a redundancy data inputting/outputting unit configured to input/output data from the redundancy cell block in response to the first input/output strobe signal, and a connection selecting unit configured to selectively connect the normal data inputting/outputting units and the redundancy data inputting/outputting unit to a plurality of local data lines in response to a address.

Abstract: A method and system is provided for measuring, guaranteeing, and reducing replication data lag time between a primary system and one or more standby systems. Each standby system determines the lag time between the generation of a consistent version of data on the primary system and the time that the consistent version is applied on the standby system. Applications can request and be guaranteed to receive data from a standby system that is identical to the state on the primary system at the time of the query, or lag the primary state only by a maximum tolerable amount. A standby system may also publish a service that guarantees a maximum lag time and withdraw the service offer when the actual lag time exceeds the guaranteed lag time. Implications for implementing synchronous and asynchronous replication as well as performance optimizations are also discussed.

Abstract: A cluster system comprises a plurality of nodes that provides data-access service to a shared storage, each node having at least one failover partner node for taking over services of a node if the node fails. Each node may produce write logs for the shared storage and periodically send write logs at predetermined time intervals to a global device which stores write logs from each node. The global device may detect failure of a node by monitoring time intervals of when write logs are received from each node. Upon detection of a node failure, the global device may provide the write logs of the failed node to one or more partner nodes for performing the write logs on the shared storage. Write logs may be transmitted only between nodes and the global device to reduce data exchanges between nodes and conserving I/O resources of the nodes.

Abstract: In a storage device incorporating a plurality of kinds of disk drives with different interfaces, the controller performs sparing on a disk drive, whose errors that occur during accesses exceed a predetermined number, by swapping it with a spare disk drive that is prepared beforehand.

Abstract: A method begins by a processing module obtaining an encoded data slice and an associated slice name. The method continues with the processing module determining a dispersed storage (DS) unit for storing the encoded data slice based on at least one of the encoded data slice and the associated slice name and estimating a performance level of the DS unit to produce an estimated DS unit performance level. The method continues with the processing module sending the encoded data slice to the DS unit for storage therein and when the estimated DS unit performance level compares unfavorably with a performance threshold, facilitating storage of the encoded data slice in temporary memory to produce a temporarily stored encoded data slice, wherein the temporarily stored encoded data slice is retrieved in response to a retrieval request when confirmation of the DS unit storing the encoded data slice has not been received.

Abstract: In a memory device, an on-die register is provided that is configured to store a row address as well as a column address of a memory cell that fails a test. Storing the row address frees testing from being limited to activating at one time only rows related to a common redundant segment. Storing the row address also guides repair using segmented redundancy. As an addition or alternative, information may be stored in an anti-fuse bank that is designed to provide access to a redundant cell but has not yet enabled access to that cell. If the information stored in the anti-fuse bank relates to the failure of the redundant cell, such information may be used to avoid repairing with that redundant cell.

Abstract: Method and computer program product for identifying a primary disk storage medium that is higher in a boot order than a secondary disk storage medium in a software RAID, and testing for a hardware failure of the primary disk storage medium during the BIOS power-on self test. The boot order of the disk storage mediums in the software RAID is automatically changed to position the secondary disk storage medium in the RAID higher in the boot order than the primary disk storage medium in response to detecting a hardware failure in the primary disk storage medium. The operating system is then booted from the disk storage medium that is highest in the boot order. A hardware failure may be detected by reading and verifying a predetermined portion of the boot partition of the disk storage medium.

Abstract: Provided is a method of managing a computer system including a plurality of storage systems and a plurality of management appliances for managing the plurality of storage systems. A first management appliance and a second management appliance hold an identifier of a first storage system and management data obtained from the first storage system. The method includes the steps of selecting a third management appliance from the plurality of management appliances when a failure occurs in the first management appliance; transmitting the identifier held in the second management appliance from the second management appliance to the selected third management appliance; and holding the identifier transmitted from the second management appliance in the selected third management appliance. Thus, it is possible to prevent, after failing-over due to an abnormality of a maintenance/management appliance, a single point of failure from occurring to reduce reliability of the maintenance/management appliance.

Abstract: The invention provides a disk array apparatus and a physical disk restoration method for managing a used area and an unused area of a faulty physical disk and shortening the time required for the physical disk to become usable by an external unit. The disk array apparatus includes: a unit for determining whether block areas of the physical disk are used areas or unused areas; a unit for recovering data in relation to block areas determined to be used areas and writing the recovered data to block areas of a spare disk corresponding to the used areas; a unit for transmitting a notification that the physical disk is usable to a host apparatus when data recovery is completed; and a unit for writing zero data to block areas of the spare disk corresponding to block areas determined to be unused areas after transmitting the notification.

Abstract: In a storage device incorporating a plurality of kinds of disk drives with different interfaces, the controller performs sparing on a disk drive, whose errors that occur during accesses exceed a predetermined number, by swapping it with a spare disk drive that is prepared beforehand.

Abstract: A RAID storage system is provided with a plurality of disk drive modules in communication with a processor through a RAID controller. Tools and processes are provided for managing failure of individual modules in the RAID, identifying and managing excess spare modules, and migrating modules among array sites to produce uniform or near-uniform array sites.

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 method and apparatus for of storing data comprising monitoring a plurality of storage units within a mass storage area and detecting when a storage unit within the mass storage area is overloaded. The method further comprising randomly distributing the data on the overloaded storage unit to the other storage units within the mass storage area.

Abstract: A memory device for use with a primary power source including: non-volatile memory; volatile memory; an interface for connecting to a backup power source; isolation logic for controlling access to the volatile memory by a host processor, said isolation logic having a first mode during which the isolation logic provides the host processor with access to the volatile memory for storing or reading data and a second mode during which the isolation logic isolates the volatile memory from access by the host processor; and a controller controlling the isolation logic, said controller programmed to place the isolation logic in the first mode when the volatile memory is being powered by the primary power source and, when power to the volatile memory from the primary power source is interrupted, to place the isolation logic in the second mode and transfer data from the volatile memory to the non-volatile memory.

Abstract: A disk array control apparatus controls a disk array having a redundant configuration with two or more disk devices and a spare disk provided for lack of redundancy in the disk array. And the disk array control apparatus includes a failure detecting unit for detecting the lack of redundancy in the disk array, and a rebuilding control unit for performing rebuilding processing on a dedicated spare disk device assigned to the disk array with the lack of redundancy, the dedicated spare disk being the spare disk dedicatedly assigned to the two or more disk arrays including the disk devices having a same characteristic as that of the spare disk.