Patent ID: 7681001

Claim:
A computer system, comprising: a management computer; a first storage system connected to a host computer and the management computer; and a second storage system connected to the host computer, the management computer, and the first storage system, wherein the first storage system comprises: a data volume including write data from the host computer; a first journal volume including journal data acquired in accordance with the corresponding write data; a first snapshot volume including snapshots, each corresponding to the data volume at a plurality of given times; and a first controller that applies a predetermined size of journal data to a snapshot at a first journal read speed, wherein the second storage system comprises: a second journal volume including journal data received from the first storage system; and a second controller that applies the predetermined size of journal data to a snapshot at a second journal read speed, which is lower than the first journal read speed, wherein the management computer comprises: a service level table that manages a designated elapsed time after acquisition of the journal data and a required recovery time, corresponding to the first storage system and the second storage system; and a processor that migrates a set of journal data from the first journal volume of the first storage system to the second journal volume of the second storage system, based on the designated elapsed time after acquisition of journal data corresponding to the first storage system defined in the service level table, wherein the processor adjusts a necessary recovery time of the second storage system, which is calculated by the second journal read speed and an amount of journal data for recovery, such that the necessary recovery time does not exceed the required recovery time defined in the service level table, and wherein the processor sends a recovery request including a designated recovery point of time to the second storage system, for applying journal data to a latest snapshot up to the designated recovery point of time within the required recovery time.