摘要 |
Restoring a mass storage device 12, including the corresponding data blocks 20 stored thereon, to a state in which it existed at a prior instant in time to minimize the data loss caused by data blocks 20 becoming corrupt or lost. After a mirrored or backup copy has been made, data blocks 40 that are to be overwritten in response to a write request are stored in a preservation memo ry 14 prior to being overwritten. The data blocks 40 stored in the preservation memory 14 are time-stamped to designate the chronological order by which the data blocks 40 were overwritten. If data becomes corrupted, the data blocks 40 of the presentation memory 14 are applied to the corrupted data 20 in revers e chronological order until such time that a valid, non-corrupted set of data obtained. In this manner, data more recent than that associated with the ful l mirrored or backup copy can be reconstructed. |