Patent ID: 8204864

Claim:
A method comprising the steps of: performing, by a storage server, a dump operation from a set of storage blocks that form a snapshot of a consistent state of an active filesystem at a past time, said snapshot taken from said active filesystem at said past time, said dump operation including copying at least a subset of said set of storage blocks from said snapshot to a plurality of secondary storage devices using a linear dump format, wherein the plurality of secondary storage devices are used to recover the set of storage blocks in the event of a system failure after the dump operation is completed; and setting a checkpoint, wherein the checkpoint comprises an indication of which blocks in the set of storage blocks said dump operation has successfully copied to one of the plurality of secondary storage devices as time proceeds, wherein the checkpoint is set to identify a physical end of an individual secondary storage device of the plurality of secondary storage devices for which the dump operation has actually completed, wherein said dump operation resumes copying to another of the plurality of secondary storage devices at a stage of the dump operation indicated by the checkpoint in the event of an interruption in performing said dump operation, and wherein the setting of a checkpoint is performed atomically, and wherein setting said each of the at least one checkpoints is performed at completion of a secondary storage device of the plurality of secondary storage devices.