Abstract: Provided are a method, system, and program for managing data in storage units. Storage pool information indicates an assignment of a plurality of storage units to a plurality of storage pools, wherein each pool is assigned zero or more storage units, wherein data associated with one storage pool is stored in a storage unit assigned to the storage pool, wherein the storage pool information for each pool indicates a threshold and target storage pool, and wherein the target storage pool is capable of being different from the storage pool. One storage unit associated with a source storage pool is selected and a determination is made of the threshold from the storage pool information for the source storage pool.

Abstract: Provided are a method, system, and program for managing storage units. Storage pool information indicates an assignment of a plurality of storage units to a plurality of storage pools, wherein each pool is assigned zero or more storage units, and wherein data associated with one storage pool is stored in at least one storage unit assigned to the storage pool. User selection is received to move at least one storage unit to a target storage pool. A determination is made of at least one storage unit assigned to a source storage pool to move to the target storage pool. The storage pool information is updated to indicate the determined at least one selected storage unit as assigned to the target storage pool.

Abstract: Disclosed is a system, method, and program for transferring data. Whether data is being transferred to physical volumes in peak mode is identified. If the data is being transferred in peak mode, whether a large chain of data is available for transfer to physical volumes is determined. If the large chain of data is not available, whether a small chain of data is available for transfer to physical volumes is determined. If the small chain of data is available, the small chain of data is transferred to physical volumes. Additionally, if one or more files that have ages greater than a steady state age threshold are available, the one or more files are transferred to the one or more physical volumes. If one or more files that have ages greater than a peak age threshold are available, the one or more files are transferred to the one or more physical volumes.

Abstract: A method and apparatus to recover a construct definition associated with a logical volume in a virtual tape server (VTS) system following a disaster situation involving a library manager database. The method and apparatus re-establish the association between a logical volume or data file or block and a construct definition or volume attribute that assigns certain actions that may be taken on the logical volumes. Such actions and constructs may be defined by a client processor or by the VTS system in order to provide quality storage media management. The constructs may be uploaded to or reconstructed within the library manager database in combination with the host or virtual tape server and consequently made available to the system. In particular, the method and apparatus are configured to recover one or more of a storage group construct, a management class construct, a storage class construct, and a data class construct associated with a logical volume within a VTS system.

Abstract: Provided are a method, system and article of manufacture for return processing in storage pools. A plurality of physical volumes are allocated to a first storage pool. A determination is made whether the first storage pool has more than a threshold number of empty physical volumes. If the first storage pool has more than the threshold number of empty physical volumes, then at least one empty physical volume is returned to a second storage pool.

Abstract: A system, method, and apparatus are provided for copying a virtual volume to multiple physical volumes within a virtual tape system. The virtual tape system may include a virtual tape server (VTS), a library manager, and a plurality of tape drive units into which cartridges may be individually mounted. The virtual tape system stores virtual volumes, each of which represents a physical volume, although one or more virtual volumes are actually stored on a real physical volume. The library manager contains a volume database with a plurality of constructs and associated storage management actions. The constructs are received from a host computer connected to the VTS, but the storage management actions may be entered directly into the library manager, independently of the host. The library manager reads the management action associated with one or more constructs of a virtual volume and, along with the VTS, determines whether multiple physical copies of the virtual volume are to be made.

Abstract: Provided are a method, system, and article of manufacture for borrow processing in storage pools. A plurality of physical volumes are allocated to a first storage pool. A determination is made whether the first storage pool has less than a threshold number of empty physical volumes. If the first storage pool has less than the threshold number of empty physical volumes, then at least one empty physical volume is borrowed to the first storage pool from a second storage pool.

Abstract: A system, apparatus, and method to recover a logical volume on a read-only physical volume, or data storage cartridge, within a dual copy data storage system, such as a virtual tape server (VTS) system. The recovery follows a disaster situation involving the primary physical volume and the requested logical volume. The system, apparatus, and method include modules and steps as required to recover a logical volume through recalling a selective dual copy of the logical volume stored on a secondary physical volume. The primary and secondary logical volumes are stored on distinct physical volumes in order to provide quality storage media management and reduce the likelihood of loss of data. The recovery and recall procedures are implemented in a manner that is substantially transparent and asynchronous to a host or client. Additionally, the recovery and recall require no additional input from the host in order to carry out the recovery of the logical volume.

Abstract: Provided are a method, system, and article of manufacture for pooling of storage. Volume attributes are assigned to a plurality of physical volumes. Pool attributes are assigned to a plurality of storage pools, wherein the pool attributes include policies for borrowing and returning the plurality of physical volumes to and from the plurality of storage pools. One of the plurality of physical volumes is allocated to one of the plurality of storage pools based on the volume attributes of the one of the plurality of physical volumes and the pool attributes of the one of the plurality of storage pools.

Abstract: Disclosed is a system, method, and program for managing an out of available space condition. A mount command for a logical volume is received that identifies one or more physical volume pools to be subsequently used for pre-migration. It is determined that one or more of the physical volume pools have no physical volumes available for storing data. Data is prevented from being written to cache by deferring completion of the mount command until the determined one or more physical volume pools has one or more physical volumes available for storing data.