Patent ID: 7085788

Claim:
A system for copying data between a plurality of storage systems, comprising: a first storage system coupled to a plurality of computers, which comprises a first logical volume storing data received from the plurality of computers; and a second storage system coupled to said first storage system, which comprises a second logical volume storing copy data of data stored in said first logical volume; wherein said plurality of computers include at least one computer issuing a write request including a write time and at least one other computer issuing a write request without a write time, when a write time is included in a write request received from one of the plurality of computers, said first storage system records the write time and sends write data and the write time to said second storage system, when a write time is not included in the write request, said first storage system assigns a write time recorded by said first storage system to the write data and sends the write data with the write time to said second storage system, and said second storage system stores the write data received from said first storage system in said second logical volume in an order based on the write time received from said first storage system, wherein said first storage system comprises a plurality of said first logical volumes, said second storage system comprises a plurality of said second logical volumes, a plurality of logical volume groups are provided, each said group including at least one said first logical volume and at least one said second logical volume, and further wherein said second storage system, in respect of each of said plurality of logical volume groups, records a latest write time in the write times assigned to the write data to be stored in said second logical volumes in each of the logical volume groups sequentially, selects the oldest write time from among the write times stored as the latest write time for each of the logical volume groups, identifies the write data to which a write time has been assigned that is earlier than the selected oldest write time, and stores the identified write data in its respective said second logical volume.