US Patent 7707375 Storage system and controller for controlling remote copying

The reconfiguration controller selects for each data whether or not to execute remote copying of data from the first storage device to the second storage device. Each data sent from the host to be stored in the first storage device contains a copy policy tag that defines the policy relating to remote copying. The reconfiguration controller determines whether or not remote copying of the each data is necessary based on the copy policy tag of the each data, and selectively transmits the data requiring remote copying to the second storage device.