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: 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: A method according to one embodiment includes copying data incoming to and/or generated at a production site to a copy cluster at a remote copy site, thereby creating a redundant copy of the data at the copy cluster. When the copy cluster becomes unavailable, data incoming to and/or generated at the production site is copied to a backup reserve site after the copy cluster becomes unavailable. Additional systems, methods, and computer programs products are also presented.

Abstract: In one embodiment, a computer program product for time-delayed replication includes a computer readable storage medium having program instructions embodied therewith. The embodied program instructions are readable and/or executable by a processor to cause the processor to receive, by the processor, data to store to a first cluster. The embodied program instructions are also readable and/or executable by the processor to cause the processor to store, by the processor, one or more copies of the data to the first cluster. Moreover, the embodied program instructions are readable and/or executable by the processor to cause the processor to set, by the processor, a time-delayed copy consistency point, the time-delayed copy consistency point indicating an amount of time in which data stored to the first cluster is aged prior to being copied from the first cluster to a second cluster.

Abstract: In one embodiment, a system includes a disk cache and a controller configured to create a cache resident partition in the disk cache, the cache resident partition being configured to store data thereto that is not subject to HSM, manage the cache resident partition to have a size that is greater than a first minimum size and less than or equal to a total size of the disk cache, receive data to store to the disk cache, store the data to the cache resident partition at least initially, create tape-managed partitions in the disk cache, each of the tape-managed partitions being configured to store data that is subject to HSM, and manage the tape-managed partitions to have a size that is greater than a second minimum size and less than or equal to a total size of the disk cache less a size of all other partitions combined.

Abstract: In one embodiment, a method for disaster recovery (DR) testing includes creating a snapshot of data based on a backup copy of data stored on one or more production clusters or a live copy of the data and storing the snapshot on more than one DR cluster within a DR family, determining which cluster within the DR family to access the snapshot from based on a consistency of the snapshot in relation to data on the one or more production clusters at a time-zero, accessing the snapshot of data stored on the determined DR cluster within the DR family only when the snapshot was made consistent with respect to data on the one or more production clusters within the DR family before the time-zero, and performing DR testing using the snapshot.

Abstract: In one embodiment, a system includes a processor and logic integrated with and/or executable by the processor. The logic is configured to cause the processor to determine which cluster within a disaster recovery (DR) family to access, via a DR host, a snapshot of data from based on a consistency of the snapshot in relation to data on one or more production clusters at a time-zero, cause the processor to allow access, via a first DR cluster, to snapshots on any of one or more DR clusters within a DR family, access the snapshot stored on the one or more DR clusters within the DR family only when the snapshot was made consistent with respect to data on the one or more production clusters within the DR family before a time-zero, and perform DR testing using the snapshot.

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, 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: In one embodiment, a method includes detecting an error while writing data to a tape volume. The method further includes repositioning the tape volume for recovering from the error, and receiving, after the repositioning, at least a portion of the data for rewriting the at least a portion of the data to the tape volume. Further, the method includes determining, after the repositioning, a current position of the tape volume. Additionally, the method includes determining, based on the current position of the tape volume, whether the rewrite to the tape volume is allowed.

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, a computer program product for time-delayed replication includes a computer readable storage medium having program instructions embodied therewith. The embodied program instructions are readable and/or executable by a processor to cause the processor to receive, by the processor, data to store to a first cluster. The embodied program instructions are also readable and/or executable by the processor to cause the processor to store, by the processor, one or more copies of the data to the first cluster. Moreover, the embodied program instructions are readable and/or executable by the processor to cause the processor to set, by the processor, a time-delayed copy consistency point, the time-delayed copy consistency point indicating an amount of time in which data stored to the first cluster is aged prior to being copied from the first cluster to a second cluster.

Abstract: In one embodiment, a system includes a processor and logic integrated with and/or executable by the processor. The logic is configured to cause the processor to determine which cluster within a disaster recovery (DR) family to access, via a DR host, a snapshot of data from based on a consistency of the snapshot in relation to data on one or more production clusters at a time-zero, cause the processor to allow access, via a first DR cluster, to snapshots on any of one or more DR clusters within a DR family, access the snapshot stored on the one or more DR clusters within the DR family only when the snapshot was made consistent with respect to data on the one or more production clusters within the DR family before a time-zero, and perform DR testing using the snapshot.

Abstract: In one embodiment, a method for disaster recovery (DR) testing includes creating a snapshot of data based on a backup copy of data stored on one or more production clusters or a live copy of the data and storing the snapshot on more than one DR cluster within a DR family, determining which cluster within the DR family to access the snapshot from based on a consistency of the snapshot in relation to data on the one or more production clusters at a time-zero, accessing the snapshot of data stored on the determined DR cluster within the DR family only when the snapshot was made consistent with respect to data on the one or more production clusters within the DR family before the time-zero, and performing DR testing using the snapshot.

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: In one embodiment, a system includes a processor and logic integrated with and/or executable by the processor, the logic being configured to cause the processor to access a snapshot of data stored on one or more DR clusters within a disaster recovery (DR) family only when the snapshot was made consistent with respect to data on one or more production clusters within the DR family before a time-zero, and perform DR testing using the snapshot, wherein the time-zero represents a time selected to simulate a disaster, wherein the DR family includes one or more DR clusters accessible to a DR host and the one or more production clusters accessible to a production host, and wherein the DR host is configured to replicate data from the one or more production clusters to the one or more DR clusters.

Abstract: In one embodiment, an apparatus includes a processor and logic integrated with and/or executable by the processor configured to cause the processor to receive data to store to a first cluster, store one or more copies of the data to the first cluster, and set a time-delayed copy consistency point time-delayed cops consistency point indicating an amount of time in which data stored to the first cluster is aged prior to being copied from the first cluster to a second cluster. In another embodiment, a method for time-delayed replication includes receiving data to store to a first cluster, storing one or more copies of the data to the first cluster, and setting a time-delayed copy consistency point, the time-delayed copy consistency point indicating an amount of time in which data stored to the first cluster is aged prior to being copied from the first cluster to a second cluster.

Abstract: In one embodiment, a system includes a processor and logic integrated with and/or executable by the processor, the logic being configured to cause the processor to define a disaster recovery (DR) family, the DR family having one or more DR clusters accessible to a DR host and one or more production clusters accessible to a production host, wherein the DR host is configured to replicate data from the one or more production clusters to the one or more DR clusters, 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, and share a point-in-time data consistency at the time-zero among all clusters within the DR family. Other systems, methods, and computer program products are presented for DR testing, according to more embodiments.

Abstract: In one embodiment, a system includes a disk cache and a controller configured to create a cache resident partition in the disk cache, the cache resident partition being configured to store data thereto that is not subject to HSM, manage the cache resident partition to have a size that is greater than a first minimum size and less than or equal to a total size of the disk cache, receive data to store to the disk cache, store the data to the cache resident partition at least initially, create tape-managed partitions in the disk cache, each of the tape-managed partitions being configured to store data that is subject to HSM, and manage the tape-managed partitions to have a size that is greater than a second minimum size and less than or equal to a total size of the disk cache less a size of all other partitions combined.