In a data recording apparatus, a monitoring unit detects a VLU including an MRB that manages an area that has not been accessed for a specified time period based on a current time, a time management table, and a parameter table. From MRBs of the detected VLU, the monitoring unit selects a plurality of MRBs with an unaccessed time period equal to or more than the specified time period and equal to or less than a total time. The monitoring unit performs synchronization process for data in a primary storage managed by the selected MRBs at a time. During the synchronization process, a correction value is adjusted when there is a data conflict with another device.