Abstract: Provided are a system, computer program, and method for restoring redundancy in a storage group when a storage device in the storage group fails. In response to detecting a failure of a first storage device in a storage group, wherein the storage group stores each of a plurality of extents in the first storage device and a second storage device to provide redundancy, a determination is made whether a spare storage device that has a storage capacity less than that of the storage group. One of the extents in a storage location in the second storage device that is beyond an upper limit of positions in the spare storage device is moved to a new storage location. The spare drive is incorporated into the storage group to provide redundant storage for the storage group, wherein the extents in the storage group are copied to the spare drive.

Abstract: A computer-implemented method for managing storage devices in a storage subsystem having an array of storage devices, according to one embodiment, includes determining that at least one storage device in the array of storage devices has failed. Storage device characteristics of the failed storage device are compared with storage device characteristics of each of a plurality of candidate devices, and an attempt is made to identify a first candidate storage device having storage device characteristics that match the storage device characteristics of the failed storage device. A second candidate storage device having storage device characteristics most similar to the storage device characteristics of the failed storage device is identified in response to not identifying a candidate device that matches the failed storage device.

Abstract: A system is provided for transforming an in-use RAID array from a first array configuration having a first parameter to a second array configuration having a second parameter while preserving a logical data structure of the RAID array. The system includes an extent reservation component, and a data migration component for reading unmigrated data from an area of an array arranged according to the first array configuration and writing the data to an area of the array arranged according to the second array configuration using reserved extents to store migrated data. The system also includes a first I/O component for performing I/O according to the first array configuration on unmigrated data prior to its reading by the data migration component, and a second I/O component for performing I/O according to the second array configuration on the migrated data after writing the migrated data.

Abstract: A method for managing storage devices in a storage subsystem having an array of storage devices, according to one embodiment, includes determining that a storage device in an array of storage devices has failed. A first candidate storage device having storage device characteristics that match storage device characteristics of the failed storage device is identified. The first candidate storage device is exchanged with a second candidate storage device in response to determining that the second candidate storage device has storage device characteristics that are more similar to the storage device characteristics of the array of storage devices than the first candidate storage device.

Abstract: A system is provided for transforming an in-use RAID array from a first array configuration having a first parameter to a second array configuration having a second parameter while preserving a logical data structure of the RAID array. The system includes an extent reservation component, and a data migration component for reading unmigrated data from an area of an array arranged according to the first array configuration and writing the data to an area of the array arranged according to the second array configuration using reserved extents to store migrated data. The system also includes a first I/O component for performing I/O according to the first array configuration on unmigrated data prior to its reading by the data migration component, and a second I/O component for performing I/O according to the second array configuration on the migrated data after writing the migrated data.

Abstract: A computer node comprises dual hard drives. A method of testing the computer node comprises performing a test of the first hard drive, waiting a specific time period, and performing a test of the second hard drive. Each test comprises isolating the drive being tested, writing data to the drive being tested, removing power from the drive being tested, repowering the drive being tested, and reading data from the drive being tested.

Abstract: A method according to one embodiment includes receiving an I/O request for data, and determining whether the I/O request refers to migrated or unmigrated data. Unmigrated data is data residing on a first portion of a drive array, the first portion being arranged in according to a first array configuration having at least a first parameter. Migrated data is data that has been migrated from the first portion to a second portion of the drive array, the second portion having a second array configuration having at least a second parameter. The method also includes using parameters corresponding to the first array configuration in response to determining that the requested data is unmigrated data. However, in response to determining that the requested data is migrated data, parameters corresponding to the second array configuration are used.

Abstract: In one embodiment, a method includes recording event history information for one or more events associated with an entity; evaluating the event history information for each of the one or more events associated with the entity against a symptom rule, wherein the symptom rule defines a validity state of a diagnosis; issuing a subscription to one or more subscribers, wherein the subscription enables the one or more subscribers to receive diagnosis information; and indicating the validity state of the diagnosis to the subscriber, wherein the recording and the evaluating are performed independently such that the issuing and the event history information and the are substantially decoupled. Other methods are also described, according to various embodiments.

Abstract: In one embodiment, a system includes a recording module adapted for recording event history information for one or more events associated with an entity, an evaluating module adapted for evaluating the event history information for each of the one or more events associated with the entity against a symptom rule, wherein the symptom rule defines a validity state of a diagnosis, an issuing module adapted for issuing a subscription to one or more subscribers, wherein the subscription enables the one or more subscribers to receive diagnosis information, and an indicating module adapted for indicating the validity state of the diagnosis to the subscriber, wherein the recording module and the evaluating module are independent such that the issuing module and the event history information are substantially decoupled. Other systems and computer program products are also described, according to various embodiments.

Abstract: Aspects of the present invention relate to an apparatus and corresponding method that includes reading data from a first portion of an in-use redundant array of independent disks (RAID), wherein the first portion of the in-use RAID is arranged according to a first array configuration having at least a first parameter. One or more reserved extents in a storage pool is used to store at least a first portion of the data for writing to the in-use RAID. One or more free extents in the storage pool and/or in the in-use RAID is used to store at least a second portion of the data for writing to the in-use RAID. The data is written to a second portion of the in-use RAID. The second portion of the in-use RAID is arranged according to a second array configuration having at least a second parameter.

Abstract: A method for managing storage devices in a storage subsystem having an array of storage devices, according to one embodiment, includes determining that a storage device in an array of storage devices has failed. A first candidate storage device having storage device characteristics that match storage device characteristics of the failed storage device is identified. The first candidate storage device is exchanged with a second candidate storage device in response to determining that the second candidate storage device has storage device characteristics that are more similar to the storage device characteristics of the array of storage devices than the first candidate storage device.

Abstract: Storing defined presets for configuration of a storage controller may include providing a storage controller interface to define a preset associated with an action of the storage controller; receiving preset parameter values for the preset via the interface; validating the preset parameter values to check that the preset is valid; storing the preset within the storage controller, and creating one or more preset objects from the preset, the preset object being accessible by the storage controller at run time. The preset may include a human-readable name; an action name indicating to which associated storage controller action the preset applies, and a set of parameter name-value pairs.

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: Aspects of the present invention relate to an apparatus and corresponding method that includes reading data from a first portion of an in-use redundant array of independent disks. (RAID), wherein the first portion of the in-use RAID is arranged according to a first array configuration having at least a first parameter. One or more reserved extents in a storage pool is used to store at least a first portion of the data for writing to the in-use RAID. One or more free extents in the storage pool and/or in the in-use RAID is used to store at least a second portion of the data for writing to the in-use RAID. The data is written to a second portion of the in-use RAID. The second portion of the in-use RAID is arranged according to a second array configuration having at least a second parameter.

Abstract: In one embodiment, a method includes reserving extents in a storage pool, reading data from a first portion of an in-use RAID arranged according to a first array configuration, using the reserved extents in the storage pool to store a first portion of the data for writing to the in-use RAID, using one or more free extents in the storage pool or in the in-use RAID to store a second portion of the data for writing to the in-use RAID, writing the data to a second portion of the in-use RAID arranged according to a second array configuration, performing one or more first I/O operations according to the first array configuration, wherein the one or more first I/O operations are performed on the data before the data is read by the data migrating component, and performing one or more second I/O operations according to the second array configuration.

Abstract: A resource system comprises a plurality of resource elements and a resource controller connected to the resource elements and operating the resource elements according to a predefined set of operational goals. A method of operating the resource system comprises the steps of identifying error recovery procedures that could be executed by the resource elements, categorizing each identified error recovery procedure in relation to the predefined set of operational goals, detecting that an error recovery procedure is to be performed on a specific resource element, deploying one or more actions in relation to the resource elements according to the categorization of the detected error recovery procedure, and performing the detected error recovery procedure on the specific resource element.

Abstract: Provided are a system, computer program, and method for restoring redundancy in a storage group when a storage device in the storage group fails. In response to detecting a failure of a first storage device in a storage group, wherein the storage group stores each of a plurality of extents in the first storage device and a second storage device to provide redundancy, a determination is made whether a spare storage device that has a storage capacity less than that of the storage group. One of the extents in a storage location in the second storage device that is beyond an upper limit of positions in the spare storage device is moved to a new storage location. The spare drive is incorporated into the storage group to provide redundant storage for the storage group, wherein the extents in the storage group are copied to the spare drive.

Abstract: Transforming an in-use RAID array from a first array configuration having a first parameter to a second array configuration having a second parameter while preserving the logical data structure. An extent reservation component and data migration component are provided for reading unmigrated data from an area of an array arranged according to the first array configuration and writing the data to an area of the array arranged according to the second array configuration using reserved extents to store first migrated data and using further extents to store second migrated data. A first I/O component for performing I/O according to the first array configuration on unmigrated data prior to its reading by the data migration component is provided along with a second I/O component for performing I/O according to the second array configuration on the first migrated data and the second migrated data after its writing by the data migration component.

Abstract: Mechanisms for ensuring data consistency in a data store are provided. The mechanisms access a parity scrub factor f and perform a check on a data group of the data store. The check on the data group includes performing a parity check on a portion of the data group, the portion being equal to 1/f of the data group, and performing a data verify on the remainder of the data group. The performing of the check is repeated for the entire data store. An offset factor is used to select the portion of the data group for the parity check. In this case, the offset factor may be incremented when the performance of the check on the data group of the data store has been repeated for the entire data store.

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.