DATA MEDIUM WITH RECOVERABLE BASIC DATA BASIS STATE AND ITS FORMATION

摘要

PROBLEM TO BE SOLVED: To reduce execution in reinstallation and to minimize time required for recovery by disconnecting an area of a data medium which has a data basic state formed in an effective area and storing a freely recoverable backup copy. SOLUTION: It is confirmed whether or not data to be packed up first exceed 50% of the whole capacity of the medium (step 1); when not, 50% of it is assigned as a backup recovery area (step 5), the rest is found as a data block for signature (step 6), and the data medium is divided corresponding to the data block for signature (step 7). Then data blocks are read out of the effective data area (step 8), compressed (step 9) simultaneously with operation for inspection totalization, and written to the backup recovery area (step 10). Then other data blocks present in the effective data area are confirmed and repeatedly processed (step 11) and then the divisions of the data medium are adjusted (steps 12).