Abstract: A computer-implemented method, according to one embodiment, includes: receiving a data volume having data from multiple tenants therein. Data in the data volume is separated into objects using tenant identifiers from metadata corresponding to portions of the data, where each object corresponds to a respective tenant. The objects are stored in object storage, and the metadata is updated with information pertaining to the object which the data in the data volume was separated into. Moreover, updating the metadata with the information is performed after the data in the data volume has been separated. Other systems, methods, and computer program products are described in additional embodiments.

Abstract: A computer-implemented method, according to one embodiment, includes: receiving a data volume having data from multiple tenants therein; separating data in the data volume into objects using tenant identifiers from metadata corresponding to portions of the data, wherein each object corresponds to a respective tenant; and storing the objects in object storage. Other systems, methods, and computer program products are described in additional embodiments.

Abstract: A dynamic premigration protocol is implemented in response to a secondary tier returning to an operational state and an amount of data associated with a premigration queue of a primary tier exceeding a first threshold. The dynamic premigration protocol can comprise at least a temporary premigration throttling level. An original premigration protocol is implemented in response to an amount of data associated with the premigration queue decreasing below the first threshold.

Abstract: In one embodiment, a computer program product for dynamic volume mounting includes a computer readable storage medium having program instructions embodied therewith. The program instructions are executable by a processing circuit to cause the circuitry to perform a method including receiving, from a host, a command directed to a volume. The command includes a parameter. A policy associated with the host is evaluated. Based on the evaluation, a value of the parameter included in the command is determined. In response to the parameter including a first value, two copies of the volume are opened. The parameter is set to include the first value when the one of the two copies of the volume is already open, and the two copies of the volume are opened in response thereto. In response to the parameter including a second value, only one of the two copies of the volume are opened.

Abstract: In one embodiment, a computer program product for disaster recovery (DR) testing includes a computer readable storage device having program code embodied therewith. The program code is readable and/or executable by a hardware processor to define a DR family including one or more DR clusters accessible to a DR host and one or more production clusters accessible to a production host, create a backup copy of data stored to the one or more production clusters, store the backup copy to the one or more DR clusters, establish a time-zero in the DR family, create a snapshot of each backup copy stored to the one or more DR clusters, share a point-in-time data consistency at the time-zero among all clusters within the DR family and perform DR testing. The DR host is configured to replicate data from the one or more production clusters to the one or more DR clusters.

Abstract: Cluster families for cluster selection and cooperative replication are created. The clusters are grouped into family members of a cluster family base on their relationships and roles. Members of the cluster family determine which family member is in the best position to obtain replicated information and become cumulatively consistent within their cluster family. Once the cluster family becomes cumulatively consistent, the data is shared within the cluster family so that all copies within the cluster family are consistent.

Abstract: An apparatus-implemented method according to one embodiment includes detecting an error while writing data to a tape volume on a tape and repositioning the tape in response to detecting the error. A determination whether a rewrite of data associated with the error to the tape volume is allowed is made based on a current position of the tape after the repositioning. The data is rewritten to the tape volume in response to determining that the rewrite of data associated with the error to the tape volume is allowed. A computer program product for protecting overwrite of a tape volume according to another embodiment includes a computer readable storage medium having program instructions embodied therewith, the program instructions readable and/or executable by a controller to cause the controller to perform the foregoing method.

Abstract: A computer-implemented method, according to one embodiment, includes: receiving a data volume having data from multiple tenants therein; separating data in the data volume into objects using tenant identifiers from metadata corresponding to portions of the data, wherein each object corresponds to a respective tenant; and storing the objects in object storage. Other systems, methods, and computer program products are described in additional embodiments.

Abstract: A computer-implemented method, according to one embodiment, includes: receiving a request for a set of data at a first data storage tier, looking up corresponding metadata to each portion of the requested set of data, using the metadata to recall each of the portions of the requested set of data from object storage, and using the portions of the requested set of data to recompile a master object, the master object having a 1-to-1 mapping to the requested set of data. Other systems, methods, and computer program products are described in additional embodiments.

Abstract: In one embodiment, a system includes a disk cache that includes a plurality of hard disk drives (HDDs) and a controller. The controller is configured to create one or more tape-managed partitions in the disk cache, each of the one or more tape-managed partitions being configured to store data that is subject to hierarchical storage management (HSM). The controller is also configured to create a premigration queue configured to service premigration data for all of the one or more tape-managed partitions. Moreover, the controller is configured to receive a premigration delay value for a first tape-managed partition, the premigration delay value defining a time period that elapses prior to queuing the premigration data for the first tape-managed partition to the premigration queue. The premigration delay value is based on a volume creation time. Other systems, methods, and computer program products are described in accordance with more embodiments.

Abstract: Various embodiments are provided for identifying matching tape volumes for data deduplication in an automated data storage library by a processor. N most similar tape volumes in a tape library may be matched according to a data indication provided in each volume header of the N most similar tape volumes for performing a data deduplication operation on a reduced block of compressed data between the N most similar tape volumes, wherein N is a positive integer.

Abstract: Various embodiments are provided for identifying matching tape volumes for data deduplication in an automated data storage library by a processor. A weak hash function on a selected block of streamed data from a host such that the selected block of streamed data with the weak hash function is further compressed to a reduced block of compressed data. N most similar tape volumes in a tape library may be matched according to the weak hash function for performing a data deduplication operation on the reduced block of compressed data between the N most similar tape volumes, wherein N is a positive integer.

Abstract: An apparatus-implemented method according to one embodiment includes detecting an error while writing data to a tape volume, and repositioning the tape in response to detecting the error. Further, the method includes determining, after the repositioning, a current position of the tape, and determining, based on the current position, whether a rewrite of data associated with the error to the tape volume is allowed. A system according to one embodiment includes a processor and logic integrated with and/or executable by the processor. The logic is configured to cause the foregoing method to occur. A computer program product according to one embodiment includes a computer readable storage medium having program instructions embodied therewith, the program instructions readable and/or executable by a controller to cause the controller to perform the foregoing method.

Abstract: In one embodiment, a computer program product for dynamic volume mounting includes a computer readable storage medium having program instructions embodied therewith. The program instructions are executable by a processing circuit to cause the circuitry to perform a method including receiving, from a host, a command directed to a volume. The command includes a parameter. A policy associated with the host is evaluated. Based on the evaluation, a value of the parameter included in the command is determined. In response to the parameter including a first value, two copies of the volume are opened. The parameter is set to include the first value when the one of the two copies of the volume is already open, and the two copies of the volume are opened in response thereto. In response to the parameter including a second value, only one of the two copies of the volume are opened.

Abstract: For maintaining a context stack, a processor monitors a stack size for a stack of a plurality of existing contexts that are not associated to a process of a plurality of processes. Each context is associable and reusable with a plurality of processes and includes a pathway to a data set when not associated to any process of the plurality of processes. The pathway includes a logical volume identifier for the data set, a logical address of the data set within the logical volume, and a logical address of an intervening device. The context defines communications between the process and the data set through the pathway when associated to the process, and each context is returned to the stack when not associated to the process.

Abstract: An apparatus-implemented method according to one embodiment includes detecting an error while writing data to a tape volume on a tape and repositioning the tape in response to detecting the error. A determination whether a rewrite of data associated with the error to the tape volume is allowed is made based on a current position of the tape after the repositioning. The data is rewritten to the tape volume in response to determining that the rewrite of data associated with the error to the tape volume is allowed. A computer program product for protecting overwrite of a tape volume according to another embodiment includes a computer readable storage medium having program instructions embodied therewith, the program instructions readable and/or executable by a controller to cause the controller to perform the foregoing method.

Abstract: In one embodiment, a system includes a processor and logic configured to create a backup copy of data stored to one or more production clusters and store the backup copy to one or more disaster recovery (DR) clusters. Moreover, the logic is configured to establish a time-zero in the DR family and create a snapshot of each backup copy stored to the one or more DR clusters. Each snapshot represents data stored to the one or more DR clusters at the time-zero, and each snapshot is a point-in-time flash copy of at least a user data portion of all virtual tapes of the one or more DR clusters with the proviso that the snapshot does not include a metadata portion of the virtual tapes. The logic is further configured to share a point-in-time data consistency at the time-zero among all clusters within the DR family.

Abstract: In one embodiment, an apparatus comprises a processor and logic integrated with and/or executable by the processor, the logic being configured to cause the processor to receive, from a host, a command directed to a volume, the command including a parameter. The logic is further configured to cause the processor to evaluate a policy associated with the host, and, based on the evaluation of the policy associated with the host, determine a value of the parameter included in the command. Still yet, the logic is configured to cause the processor to open two copies of the volume in response to the parameter including a first value, and open only one of the two copies of the volume in response to the parameter including a second value.

Abstract: An apparatus, system, and method are disclosed for maintaining a context stack. A monitor module monitors a stack size after each monitor interval for a stack of a plurality of contexts. Each context defines communications between a process and a data set and comprises a pathway for communicating with the data set and a process identifier. A stack module deallocates a context that satisfies a stack policy from the stack if the stack size is within a buffer threshold of a maximum threshold.

Abstract: Cluster families for cluster selection and cooperative replication are created. The clusters are grouped into family members of a cluster family base on their relationships and roles. Members of the cluster family determine which family member is in the best position to obtain replicated information and become cumulatively consistent within their cluster family. Once the cluster family becomes cumulatively consistent, the data is shared within the cluster family so that all copies within the cluster family are consistent.