Abstract: A virtual data storage system stores data as data objects to a plurality of storage devices in accordance with storage management policies. Storage pools define groups of medial 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. Copy and delete actions are preformed to manage copies of data objects among the storage pools in accordance with the policy. As an extension of the storage management policies, the process of creating export media sets is automated. These processes can also be used to create backup media. When an export media set is created, subsequent commands are prevented from modifying the media in the export media set. When a backup is created, subsequent commands are prevented from overwriting media containing data referred to by the manifest media for the backup.

Abstract: A virtual data storage system includes a device emulator and a storage system. The virtual data storage system requires the performance of activities on a scheduled basis. An activity scheduler manages a set of pending, running, and completed activities. The activity scheduler provides scheduler services for use by external processes. A scheduler process examines a list of to-be-run activities. For each activity that has reached its scheduled time, that activity is considered for starting. An activity monitor process monitors started activities. Upon determining a problem with an activity, a recovery process is performed. The recovery process includes returning the problem activity to the list of to-be-run activities.