Patent ID: 7930498

Claim:
A method of managing mapping information for creating in a second storage system a replica of a snapshot volume in a first storage system; wherein the first storage system includes a first file system having a first source volume that contains data, and having a second source volume; the method comprising: storing mapping information of the first source volume and the second source volume in the first storage system; copying, in the second source volume, data from files or blocks that were on the first source volume prior to the files or blocks being changed on the first source volume, the data being copied following each predetermined point in time that a snapshot is taken; sending to the second storage system, information regarding the first source volume and the second source volume in the first file system; receiving from the second storage system information regarding a first target volume in the second storage system and a second target volume in the second storage system, the first target volume receiving replication of the first source volume, the second target volume receiving replication of the second source volume; and sending transfer information to the second storage system, the transfer information being provided using the information received from the second storage system, the transfer information including the mapping information of the first source volume and the second source volume and information of the first and second target volumes.