US Patent 7860832 Systems and methods for maintaining data files

In a storage system having a source storage system and target storage system, systems and methods maintain information from which a set of source data files stored on a storage system can be retrieved. In one embodiment, baseline images of one or more source data files are stored in target files of the target storage system. For a selected target storage time, locations in the source storage system where changes have been made since a previous target storage time are dynamically identified. Contents that occupy the locations are read and sent to the target storage system. The contents are stored in the target storage system together with associations of the contents with the locations.