Patent ID: 7865680

Claim:
A remote copy system for copying write data, which is sent from a host system to a first storage system configuring a local site, from said first storage system to a second storage system configuring a remote site, wherein said first storage system comprises: a primary data volume to which said write data is written; a first controller for creating journal data from said write data; a primary journal volume for storing the created journal data; and a second controller for transferring the journal data stored in said primary journal volume to said second storage apparatus; wherein said second storage system comprises: a secondary journal volume for storing the journal data transferred from said first storage apparatus; a secondary data volume corresponding to said primary data volume; a replica volume corresponding to said secondary volume; a third controller wherein said journal data is given a time stamp; and wherein said third controller continues to receive said journal data transferred from said first storage apparatus to store said received journal data in said secondary journal volume while said third controller: (a) restores said journal data to said secondary data volume from said secondary journal volume and split a pair between said secondary data volume and said replica volume until a designated time; (b) stops restoring said journal data to said secondary data volume from said secondary journal volume and starts to replicate data stored in said secondary data volume to said replicated volume when said time stamp exceeds said designated time and (c) resumes to restore said journal data to said secondary data volume from said secondary journal volume and splits pair between said secondary data volume and said replica volume after said third controller finishes replicating data stored in said secondary data volume to said replicated volume.