Patent ID: 7386755
Filing Date: 2008-06-10
Classification: G06F

Abstract:
1. A data restoring method for restoring data stored in a second storage system in a storage subsystem including a first storage system and a second storage system, each of which is connected to a host via a communication channel, in which the second storage system stores a copy of data to be transmitted from the first storage system, wherein the first storage system processes an I/O request from the host, and as a result of I/O processing of the second storage system, transmits updated data according to said I/O request, the second storage system retains data received from the first storage system as update log data, and the host transmits a command for settling a state of an application to the first storage system as data, the first storage system transmits the data to the second storage system, and the host and the second storage system both retain an identifier corresponding to the command, and relate the identifier to the log data whereby the host designates the identifier at any given time to thereby restore data at any given time by the second storage system.