A storage system includes a plurality of storage devices connected together, where the plurality of storage devices include a copy-source storage device having data to be copied and copy-target storage devices capable of receiving the copied data. The copy-source storage device includes a copy-source controller for checking parameters contained in a buffer newly setting command to determine a group of storage devices to be subjected to a newly setting of a buffer and a copy-target storage device in the group and transmitting the parameters to the specified copy-target storage device. The copy-target storage device includes a copy-target controller for performing a buffer newly setting process in the specified copy-target storage device on the basis of the parameters received from the copy-source storage device and notifying the copy-source storage device of a result of the buffer newly setting process.