Patent ID: 6694413
Filing Date: 2004-02-17
Classification: G06F,Y10S

Abstract:
A method of managing snapshot information in a computer system including a computer and a storage system coupled to the computer, the storage system having a disk controller and at least a first storage unit and a second storage unit connected to the disk controller, the method comprising:setting the storage system in a mode to be synchronized; and maintaining duplicate data in the first storage unit and the second storage unit; using the disk controller, writing data to both the first storage unit and the second storage units; setting the storage system in a mode for acquiring a snapshot using data in the second storage unit; using the disk controller, writing data to the first storage unit; maintaining as differential information, storage locations of data to be updated according to each write request; setting the storage system in a mode for being resynchronized; copying data stored in the storage locations maintained as differential information from the first storage unit to the second storage unit; thereby assuring that the first storage unit and the second storage unit have duplicate data.