Patent ID: 7243197
Filing Date: 2007-07-10
Classification: G06F,Y10S

Abstract:
1. A storage system comprising: a first data volume storing data of a first journal group; a second data volume storing data of a second journal group; snapshot storing areas storing at least one snapshot of at least a portion of each of the first and second data volumes; a first journal storing area storing journal entries associated with the first journal group; and a second journal storing area storing journal entries associated with the second journal group; wherein the first journal storing area is configured to permit data recovery within a first determined range by using said at least one snapshot of at least a portion of the first data volume and a portion of the journal entries stored in the first journal storing area, wherein the second journal storing area is configured to permit data recovery within a second determined range by using said at least one snapshot of at least a portion of the second data volume and a portion of the journal entries stored in the second journal storing area, wherein the storage system releases at least one of the stored journal entries from the first or second journal storing areas while permitting data recovery within the first and second determined ranges; and wherein in order to recover data of a portion of the first or second data volume at a specific point in time within the first or second determined range, the storage system recovers the data of the portion of the first or second data volumes at the specific point in time by using said at least one snapshot and a portion of the stored journal entries.