Abstract: A data deduplication method providing direct look up and storage in an instance repository (IR). The method includes receiving a data object and processing the data object to generate a fingerprint that includes a location component, which defines a file location within the IR such as by first using a hash function to create a hash for the data object and parsing the hash value into sub-strings defining sub-directories of the IR. The method includes determining whether the data object is a duplicate by verifying the presence of a file in the IR at the file location. Determining if the data is unique involves performing a system call on the IR providing the location component as the file path. The method includes, when a file is not in the IR, updating the IR to store the data object as a file at the file location defined by the location component.

Abstract: A virtual data storage system stores data as data objects to a plurality of storage devices in accordance with storage management policies. The system manages multiple copies of stored data objects on multiple media types over time. Storage pools define groups of media that are to be treated in a uniform manner. A policy is composed of a series of policy copy/delete rules that direct movement of data objects into the storage pools. A rule defines a destination storage pool, a length of time that the data objects are to remain in the destination storage pool, and a data source for the data objects. Copy and delete actions are performed to manage copies of data objects among the storage pools in accordance with the policy.

Abstract: A data deduplication method providing direct look up and storage in an instance repository (IR). The method includes receiving a data object and processing the data object to generate a fingerprint that includes a location component, which defines a file location within the IR such as by first using a hash function to create a hash for the data object and parsing the hash value into sub-strings defining sub-directories of the IR. The method includes determining whether the data object is a duplicate by verifying the presence of a file in the IR at the file location. Determining if the data is unique involves performing a system call on the IR providing the location component as the file path. The method includes, when a file is not in the IR, updating the IR to store the data object as a file at the file location defined by the location component.

Abstract: A virtual data storage system includes a device emulator and a storage system for storing data to a plurality of physical devices in accordance with storage management policies. The data received by the device emulator is converted into a data object. The data object and object specific metadata are stored to storage media in accordance with the storage management policies. The object specific metadata is stored separate from the data object. In addition, the object specific metadata is embedded into the data object. Upon detecting an error when attempting to access the data object, an extent of data loss is determined by examining the object specific metadata.

Abstract: A virtual tape storage system includes an original virtual tape library for storing data and includes snapshot virtual tape library (SVTL). The SVTL includes a snapshot of the data stored in the original virtual tape library. A host is operable to receive the snapshot data from the SVTL to perform a disaster recovery test of the original virtual tape library. The SVTL is generated from the original virtual tape library using a copy-on-write snapshot process. In an embodiment, the original virtual tape library stores the stored data on a number of virtual tape volumes (VTVs), and the SVTL includes a snapshot of those VTDs and VTVs which are required for a disaster recovery test of the original virtual tape library. In this case, the host uses the SVTL to perform the disaster recovery test of the original virtual tape library.

Abstract: A virtual tape system and method for mapping variable sized data blocks from a host to a fixed sized data block structure of a direct access storage device (DASD) utilizes a buffer between the cache and the host. The control logic operates to access the storage device by transferring data between the cache and the buffer in fixed chunk sizes, and in parallel, transferring data between the host and the buffer in data-chained blocks.