Patent ID: 6665815
Filing Date: 2003-12-16
Classification: G06F

Abstract:
A method of protecting computer data, said method comprising the steps of:acquiring a first state snapshot S1 of a first data volume consistent state at a time t1; acquiring a second state snapshot S2 of a second data volume consistent state at a time t2>t1; generating a first precedent snapshot difference list S21 comprising an identification of data blocks of said first state snapshot S1 differing from data blocks in said second state snapshot S2; creating a first precedent backup B21 by copying from said first state snapshot S1 data blocks identified in said first precedent snapshot difference list S21, said first precedent backup B21 further comprising said first precedent snapshot difference list S21; deleting said first state snapshot S1 following said step of generating a first precedent snapshot difference list S21; retrieving said first precedent backup B21; recovering said first precedent snapshot difference list S21 from said first precedent backup B21; and restoring said first state snapshot S1 by overwriting at least a portion of said second state snapshot S2 with the contents of said first precedent backup B21.