Patent ID: 7330948

Claim:
A migration method of an asynchronous remote copy pair in a system comprising primary site and secondary site, wherein the primary site includes a first primary storage system having a plurality of first primary volumes including a source primary volume and a first primary controller controlling the plurality of first primary volumes, and a second primary storage system having a plurality of second primary volumes including a destination primary volume and a second primary controller controlling the plurality of second primary volumes, the secondary site includes a first secondary storage system having a plurality of first secondary volumes including a source secondary volume and a first secondary controller controlling the plurality of first secondary volumes, and a second secondary storage system having a plurality of second secondary volumes including a destination secondary volume and a second secondary controller controlling the plurality of second secondary volumes, between the primary site and the secondary site, a plurality of asynchronous remote copy pairs of a primary volume and a secondary volume, in which an asynchronous remote copy pair of the source primary volume and the source secondary volume is included, are defined, and the first primary controller, the second primary controller, the first secondary controller, and the second secondary controller execute asynchronous remote copy processing for the plurality of asynchronous remote copy pairs to write data in first and second secondary volumes based on an order of write requests issued for first and second primary volumes, the migration method comprising steps of: a first copying step for copying data stored in the source primary volume to the destination primary volume; a second copying step for copying data stored in the source primary volume to the destination secondary volume via one of the second primary storage system or the first secondary storage system to define an asynchronous remote copy pair between the destination primary volume and the destination secondary volume; an I/O destination change step for changing destination of an I/O request from the source primary volume to the destination primary volume; and an asynchronous remote copy processing step for executing asynchronous remote copy processing for the defined asynchronous remote copy pair between the destination primary volume and the destination secondary volume and the plurality of asynchronous remote copy pairs, and writing data in the first secondary volumes and the second secondary volumes including the destination secondary volume based on an order of write requests issued for the first primary volumes and second primary volumes including the destination primary volume, whereby the asynchronous remote copy pair between the source primary volume and the source secondary volume is migrated to the asynchronous remote copy pair between the destination primary volume and destination secondary volume.