Patent ID: 8176273

Claim:
A backing-up apparatus that produces, for each time point at which backing up is executed, a snapshot representing original data at the time point at which the backing up is executed for the original data to be backed up, the apparatus comprising: an allocating unit that, upon receiving an instruction to execute the backing up, allocates, with respect to each time point designated by the instruction, a storage area to store a snapshot produced at a time point designated by the instruction; a checking unit that, on the occasion that original data is updated after the time point designated by the instruction, checks whether the original data corresponding to a place for which the updating has been executed at a time point immediately before the time point designated by the instruction is stored in the storage area allocated by the allocating unit as a storage area to store the latest snapshot produced for the immediately previous time point; and a storing unit that, on the occasion that the checking unit confirms that the original data is not stored, stores the original data immediately before the updating in only the storage area for the latest snapshot, the original data immediately before the updating corresponding to the place for which the updating has been executed.