Patent ID: 9092379
Filing Date: 2015-07-28
Classification: G06F,Y10S

Abstract:
1. A storage system comprising: a plurality of data volumes storing data sent from a computer; a snapshot storing area storing a plurality of snapshots; a journal storing area storing journal entries associated with the data, the journal entries including at least one journal entry between a first point in time and a second point in time; and a storage controller configured to store a management table including information which identifies one or more of the data volumes as a journal group, and associates one or more of the journal entries and one or more of the snapshots with the one or more of the data volumes, the storage controller further configured to conduct write operations to the data volumes according to write requests received from the computer, to manage snapshot operations to store the snapshots of the journal group, and to perform data recovery of the journal group with a target time using at least one of the journal entries and a snapshot selected from the snapshots identified in the management table for the journal group, wherein each of the journal entries includes a unique sequence number assigned by the storage system when a corresponding one of the journal entries is generated, wherein the storage system is configured to manage journal operations to record the journal entries of the journal group, wherein, to perform data recovery for the one or more of the data volumes of the journal group, the storage controller selects a snapshot that is closest in time to the target time from the plurality snapshots as the selected snapshot, and applies at least one journal entry to the selected snapshot in sequential order to perform the data recovery by referring to the unique sequence numbers of the journal entries and the management table, wherein said journal storing area stores journal entries for write data to said plurality of said data volumes in said journal group, and wherein the unique sequence numbers of the journal entries are unique within the journal group.