Abstract: Provided are a storage system and its control method having superb functionality of being able to notify an administrator of the extent of impact of a pool fault in an easy and prompt manner. The foregoing storage system and its control method manage a storage area provided by a storage medium by dividing it into multiple pools, provide a virtual logical device to a host system, dynamically allocate a storage area to the logical device according to a data write request from the host system for writing data into the logical device, move data that was written into the logical device to another pool according to the access status from host system to such data, identify, when a fault occurs in any one of the pools, an extent of impact of the fault based on the correspondence relationship of the logical device and the pool, and notify the identified extent of impact of the fault to an administrator.

Abstract: In one aspect, a method includes forming a virtualized grid consistency group to replicate logical units, running a first grid copy on a first data protection appliance (DPA), running a second grid copy on a second DPA, splitting to the first DPA IOs intended for a first subset of the logical units and splitting to the second DPA IOs intended for a second subset of the logical units different from the first subset of logical units.

Abstract: Pursuant to execution of a predetermined failback policy, if a storage device is not preexistent in a source storage system operable in the computing environment, and an owner of the storage device is one of a DR storage system and a storage system having previously withdrawn from a replication grid, and the DR storage system has authorization to transfer ownership of the storage device by a replacement operation, an instance of the storage device is replicated to the source storage system to generate a replicated instance of the storage device on the source storage system, and ownership of the storage device is designated as the source storage system for each of the instance and the replicated instance of the storage device.

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 is provided for facilitating data replication in a storage system. A logical volume of a first storage array of a replicated pair is preconfigured with one or more logical volume attributes, which include a compressible configuration bit that indicates whether data blocks to be stored to that logical volume are compressible during replication. Subsequently, with receipt of a data block at the first storage array to be stored to the logical volume, a check of the compressible configuration bit is made to determine whether the data block is compressible during replication, and if so, the data block is compressed for replication. The compressible configuration bit is placed into the payload region of the data packet being replicated to the second storage array. At the second storage array, the compressible configuration bit is used to determine whether to uncompress the replicated data block.

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: Computer program product, system and method are provided for facilitating data replication in a storage system. A logical volume of a first storage array of a replicated pair is preconfigured with one or more logical volume attributes, which include a compressible configuration bit that indicates whether data blocks to be stored to that logical volume are compressible during replication. Subsequently, with receipt of a data block at the first storage array to be stored to the logical volume, a check of the compressible configuration bit is made to determine whether the data block is compressible during replication, and if so, the data block is compressed for replication. The compressible configuration bit is placed into the payload region of the data packet being replicated to the second storage array. At the second storage array, the compressible configuration bit is used to determine whether to uncompress the replicated data block.

Abstract: A technique for avoiding a ping-pong effect on active-passive paths in a storage system managing one or more logical storage units (LUNs) on behalf of one or more host systems. A first path to the LUNs is designated as an active path and a second path to the LUNs is designated as a passive path. The first path is also designated as a preferred path to the LUNs. In response to a path failure in which a host system cannot access the LUNs on the first path, a failover operation is implemented wherein the second path is designated as the active path and the first path is designated as the passive path. The designation of the first path as the preferred path to the LUNs is not changed. Subsequent failback operations are conditionally inhibited so that only the failover host that initiated the failover is permitted to initiate a failback.

Abstract: Provided is a storage apparatus for providing a logical storage area as a data storage area to an external apparatus, comprising: a physical storage medium for creating the logical storage area; first and second storage control modules each of which is communicatively coupled to the physical storage medium to control data input/output processing between the external apparatus and the logical storage area; and first and second power supply modules each of which supplies power to the physical storage medium and the first and second storage control modules and includes a blower for generating a cooling airflow to cool down the physical storage medium and the first and second storage control modules, wherein the blower of the first power supply module generates a first cooling airflow which flows through the physical storage medium, the first storage control module, and the first power supply module, the blower of the second power supply module generates a second cooling airflow which flows through the physical s

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: Data written in the primary logical volume of the first storage device are transmitted to the third storage device via the second storage device, the data being written in the same location as the primary logical volume within the secondary logical volume in the third storage device; when transmission of the data stops among the first to the third storage devices, the respective second storage device and the third storage device manage locations in the secondary logical volume where the data held thereby are to be written; and, when transmission of the data resumes among the first to the third storage devices, the locations in the secondary logical volume managed by the respective second and the third storage devices are aggregated, the data to be written in the respective aggregated location in the secondary logical volume being transmitted from the first storage device to the third storage device via the second storage device.

Abstract: Information system, including: first and second storage apparatuses connected to a host computer and including volumes designated by a common volume identifier, but being accessible via differing paths of differing priorities. A failure detection storage apparatus connected to the storage apparatuses includes a third volume. Any I/O request designating the common volume identifier, is first sent to the first volume though the first access path, but upon error is then sent to the second volume thorough the second access path. The first or second storage apparatus detecting failure stores, in the third volume, a failure information flag. Upon receiving an 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 method begins when a dispersed storage (DS) processing unit of a DS unit has at least one of DS unit operational data and DS unit operating system algorithm to store. The method continues with the DS processing unit encoding at least a portion of the at least one of DS unit operational data and DS unit operating system algorithm in accordance with an error coding dispersal storage function to produce a plurality of data slices. The method continues with the DS processing unit storing at least some of the plurality of data slices in memory devices of the DS unit in accordance with the error coding dispersal storage function.

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: A node in a server cluster is designated as a quorum disk. The node stores a list of other nodes in the server cluster also designated as quorum disks. The node can replace the first list with a second and more recent list of quorum disks only if the second list is updated on at least a simple majority of quorum disks on the first list.

Abstract: In control of the disk array device (backup system), when a blackout occurs, the disk array device is first operated in a first method to backed up a main memory by using a power supply from a battery. During the first method, a blackout continuous time and the like are integrated, and at a timing in which the integrated value satisfies a condition, the first method is then shifted to the second method to evacuate data from the main memory onto a nonvolatile memory based on a power supply.

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: A method, apparatus, and computer program product for realizing application high availability are provided. The application is installed on both a first node and a second node, the first node being used as an active node, and the second node being used as a passive node. The method includes: monitoring access operations to files by an application during its execution on the active node; replicating the monitored updates to the file by the application from the active node to a storage device accessible to the passive node if the application performs updates to a file during the access operations; sniffing the execution of the application on the active node; and switching the active node to the second node and initiating the application on the second node in response to sniffing a failure in the execution of the application on the active node.

Abstract: A suite of network-based services, such as the services corresponding to Microsoft® SharePoint™, are provided to users with high availability. The suite of network-based services may include browser-based collaboration functions, process management functions, index and search functions, document-management functions, and/or other functions. In particular, the indexing service associated with the suite of network-based services may be provided with high availability.

Abstract: In a storage system for performing data backup using a battery during blackout, when the blackout continues for a long time, problems such as the loss of volatile memory data due to the consumption of battery capacity and the difference in recovery time between controller units after power recovery occur during restarting of the system. The present invention solves the problems by selecting (a1) battery backup or (a2) saving of data in a nonvolatile device based on the battery capacity or setting of modes, and selecting (b1) inhibiting restart of the system or (b2) storing of data in the volatile memory to a nonvolatile memory means and performing access via write-through based on the remaining capacity of the battery when restarting the system after power recovery. Further, the system enables to increase and decrease the volatile memory capacity of the write area and mutually confirms synchronization of controller units and contents of volatile memories.

Abstract: A storage system, method and program product, the system comprising: storage devices; and a controller configured to: provide virtual volumes to a host computer; manage logical units on the storage device and storage pools; allocate, in response to receiving a write request to a virtual volume, a storage region of the storage pools; and store data related to the write request in the storage region allocated, wherein the controller is further configured to: allocate first storage region in first storage pool to first virtual volume based on first size of the first storage region or the first virtual volume; allocate a second storage region in a second storage pool to a second virtual volume of the plurality of virtual volumes based on a second size of the second storage region or the second virtual volume.

Abstract: A virtual recovery server is described herein. The virtual recovery server is a software implementation on a storage server which generates a virtual server to replace a physical server when the physical server becomes inaccessible. While the physical server is inaccessible, the virtual recovery server is able to mimic the actions and data contained on the physical server. Thus, when users attempt to access an application or data that is on the physical server, they will not experience an interruption and will continue to access the information as if the physical server were up and running. The virtual recovery server is able to run for up to a number of days. When a new or repaired physical server is available the virtual recovery server is deleted after the data acquired by the virtual server is transmitted to the new physical server.

Abstract: A system and method for high speed data recording includes a control computer and a disk pack unit. The disk pack is provided within a shell that provides handling and protection for the disk packs. The disk pack unit provides cooling of the disks and connection for power and disk signaling. A standard connection is provided between the control computer and the disk pack unit. The disk pack units are self sufficient and able to connect to any computer. Multiple disk packs are connected simultaneously to the system, so that one disk pack can be active while one or more disk packs are inactive. To control for power surges, the power to each disk pack is controlled programmatically for the group of disks in a disk pack.

Abstract: Memory systems and related defective block management methods are provided. Methods for managing a defective block in a memory device include allocating a defective block when a memory block satisfies a defective block condition. The allocated defective block is cancelled when the allocated defective block satisfies a defective block cancellation condition.

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: A method, apparatus, article of manufacture, and system are presented for establishing redundant computer resources. According to one embodiment, in a system including a plurality of processor devices and a plurality of storage devices, the processor devices, the storage devices and the management server being connected via a network, the method comprises storing device information relating to the processor devices and the storage devices and topology information relating to topology of the network, identifying at least one primary computer resource, selecting at least one secondary computer resource suitable to serve as a redundant resource corresponding to the at least one primary computer resource based on the device information and the topology information, and assigning the at least one secondary computer resource as a redundant resource corresponding to the at least one primary computer resource.

Abstract: A storage device with multiple storage units, which is applicable to a system end. The storage device is a hard disk drive (HDD) or solid state disk (SSD) with a standard size. The storage device includes a first storage unit and at least one memory storage unit. The memory storage unit and the first storage unit serve to back up and update each other. The storage device further includes a multiplex control unit and a power control unit connected to the multiplex control unit. According to the decision of the multiplex control unit, the power control unit controls turning on/off of the first storage unit and the memory storage unit.

Abstract: A method and system for protecting against failure of hardware elements (HEs) in a virtual machine system using an information model with virtualization support. Based on the information model, the method boots virtual machine monitors (VMMs), virtual machines (VMs) and operating systems (OSes). The information model includes a graph of objects representing configured relationships between the hardware elements (HEs), VMMs, VMs, and OSes through parent child relationships between the graph's objects. The graph of objects includes: a domain object, HE objects, VMM objects, VM objects, and OS objects. The VM objects of a migration-enabled type represent those of the VMs that may migrate between the VMMs. Based on the runtime associations between the VMM objects and the VM objects of the migration-enabled type, the method identifies which of the migration-enabled VMs are hosted by a same HE and are therefore vulnerable to hardware failure of the same HE.

Abstract: Subject matter disclosed herein relates to on-the-fly remapping a memory device by hardware-switching data paths to locations of the memory device.

Abstract: Techniques directed to an update package including a set of instructions used for, in a remote client device, creating a new data image from a base data image are provided. A method for generating an update package includes determining differences between a base data image and a new data image, generating COPY instructions corresponding to respective sections of code in the base data image, organizing the COPY instructions into a directed acyclic graph, performing cycle detection on the COPY instructions in the directed acyclic graph to detect any cycles, when a cycle is detected, identifying a COPY instruction in the detected cycle with a smallest overlapping part, removing the overlapping part from the identified COPY instruction, and generating a COPYBACK instruction including the overlapping part removed from the identified COPY instruction, and after all cycles have been detected, generating the update package based on the COPY and COPYBACK instructions.

Abstract: A system includes a source storage device, a target storage device, a host coupled to the source storage device and the target storage device, and a first migration device coupled to the source storage device and the target storage device. The first migration device includes a first virtual storage device. The first migration device is configured to migrate data from the source storage device to the target storage device, and the first virtual storage device is configured to receive write access requests for the data from the host during the data migration and send the access request to the source storage device and target storage device.

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: Methods and structure for resuming background tasks in a storage environment. storage controller. The system is operable to receive host Input/Output (I/O) requests directed to a logical volume, and to couple with one or more of storage devices provisioning the logical volume. The system is further operable to process the host I/O requests directed to the logical volume, to initiate a background processing task distinct from the host I/O requests and related to the logical volume, and to store progress information on at least one of the one or more storage devices describing progress of the background processing task.

Abstract: According to the presently disclosed subject matter there is provided inter alia, a method and system which enable to uncover errors which are correctable by a data integrity mechanism in a computer system. The same data is read with the help of two different types of read commands. The first command is a read command which does not implement an inherent ECC and therefore does not correct corrupted data. The second command is a read command which includes an ECC and is adapted to correct errors which are detected in the data which is being read. The data obtained by each of the two read commands is compared, and in cases where a difference is identified between the two data, it is determined that an error has been detected and corrected by the ECC.

Abstract: A technique automatically handles a failure during online data migration from a source array to a target array. While a host initially accesses data from the source array using multipath I/O software, the technique involves (i) transitioning the source array to a passive mode, and the target array to an active mode, and (ii) beginning a data transfer operation which transfers data from the source array to the target array. The technique further involves modifying the data on both the target array and the source array in response to modification commands sent to the target array from the host while the data transfer operation is ongoing. The technique further involves automatically failing back to providing access to the data from the source array in response to an event in which the target array loses communication with the source array for a predefined amount of time.

Abstract: Various embodiments for disaster recovery (DR) production takeover in a computing environment by a processor device are provided. If, for a designated storage system operable in the computing environment, a takeover operation may be executed, and a DR storage system has validly replaced the designated storage system using a replacement process, a withdrawal of a DR mode of operation is performed, and ownership of at least one storage device operable in the computing environment is transferred to the DR storage system. The replacement process authorizes the DR storage system to transfer the ownership while withdrawn from the DR mode of operation.

Abstract: A computer-implemented method for improving redundant storage fault tolerance may include 1) identifying a plurality of storage devices storing an encoded set of data, with the encoded set of data including a redundant form of an underlying set of data, 2) determining that a subset of the plurality of storage devices have failed, 3) reconstructing encoded data lost due to the failure of the subset of the plurality of storage devices, and then 4) redundantly storing the reconstructed encoded data on the plurality of storage devices. Various other methods, systems, and computer-readable media are also disclosed.

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 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 method begins when a dispersed storage (DS) processing unit of a DS unit has at least one of DS unit operational data and DS unit operating system algorithm to store. The method continues with the DS processing unit encoding at least a portion of the at least one of DS unit operational data and DS unit operating system algorithm in accordance with an error coding dispersal storage function to produce a plurality of data slices. The method continues with the DS processing unit storing at least some of the plurality of data slices in memory devices of the DS unit in accordance with the error coding dispersal storage function.

Abstract: Embodiments of the present invention provide methods, apparatuses, systems, and computer software products for data storage. A first copy of a logical volume is created. A second copy of the logical volume is created based on the first copy of the logical volume, such that the first and second copies are represented by respective first and second sets of pointers to physical storage locations in which data used by the copies is stored. Responsively to a corruption of at least part of the data that is used by the first copy. The first copy is restored from the second copy by replacing the first set with the pointers in the second set.

Abstract: In one embodiment, a computer program product includes a computer readable storage medium having computer readable program code embodied therewith, configured for: validating a replication of copy services between a first storage system and a second storage system, removing a plurality of existing copy relationships between the first storage system and a failed storage system, creating a plurality of copy relationships between the first storage system and the second storage system, and synchronizing a plurality of data between the first storage system and the second storage system. In more embodiments, a system includes logic for performing the above functionality, and a method includes steps for performing the above functionality.

Abstract: An apparatus, system, and method are disclosed for reconfiguring an array of solid-state storage elements. The method includes determining that one or more storage elements are unavailable to store data. The storage elements are configured in an array of N storage elements that each store a portion of a first ECC chunk and P storage elements that store first parity data corresponding to the first ECC chunk. The method includes generating a second ECC chunk comprising at least a portion of the data of the first ECC chunk. The method includes storing the second ECC chunk and associated second parity data across (N+P)?Z storage elements where 1?Z?P.

Abstract: The storage system includes a plurality of first disk devices, a plurality of second disk devices, in which a lifetime of the plurality of second disk devices is different from a lifetime of the plurality of first disk devices, and a controller coupled to the plurality of first disk devices and the plurality of second disk devices. The controller configures a first logical unit by the plurality of first disk devices and a second logical unit by the plurality of second disk devices, provides the first and the second logical units to a host computer, and manages a first remaining available time of the first logical unit and a second remaining available time of the second logical unit, on logical unit basis.

Abstract: The computer system is capable of improving performance, reliability and redundancy. The computer system comprises: a plurality of server computers having different functions, the server computers being mutually connected by communication lines; a standby server computer being connected to each of the server computers by the communication lines, the standby server computer being capable of performing the function of each of the server computers; a detection unit for detecting an abnormal state of each of the server computers; and a take-over unit for controlling the standby server computer to take over the action of the abnormal server computer when the abnormal state of the abnormal server computer is detected by the detection unit.

Abstract: A system includes a first database, a second database, a third database, and an application server. The first database server includes a database instance. The second database server is in communication with the first database server. The second database server includes a mirror of the database instance. The third database server is in communication with the second database server. The third database server is configured to store a copy of a database within the database instance. The application server is configured to be placed in communication with the first, second, and third database servers, configured to fail over between the first and second database servers, and further configured to fail over between the second and third database servers.

Abstract: Systems, methods, and other embodiments associated with a backup utility are described. One example system causes a backup utility to identify a remote device as local to a client device. Backup data may then be retained on the remote device identified by the backup utility as being local.

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 system for disaster recovery rehearsals using copy-on-write may include a data set of an application and a disaster recovery manager. The disaster recovery manager may be configured to perform a disaster recovery rehearsal using a copy-on-write snapshot of the data set.

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.