Storage system, copy control method, and computer system

A copy control method by a storage system coupled to another storage system and a higher-level apparatus via a network to copy write data from the higher-level apparatus to the other storage system, the storage system including:

• a plurality of interface units each having a plurality of ports couplable to the network;
• and
• a plurality of controllers each being coupled so as to correspond to each of the interface units, the method comprising:
• when write data is received from the higher-level apparatus via a first port coupled to an interface unit coupled to a controller to which a storage system belongs, selecting a second port for transmitting the write data to the other storage system among the ports of the interface unit coupled to the controller to which the storage system belongs;
• and
• transmitting the write data to the other storage system via the second port.

A computer system including a host computer, a first storage system, and a second storage system, wherein

• the first storage system includes:
• a plurality of interface units each having a plurality of ports couplable to the network;
• and
• a plurality of controllers each being coupled so as to correspond to each of the interface units,
• the controller includes a processor unit, and
• when the processor unit receives write data from the higher-level apparatus via a first port of the interface unit coupled to a controller to which the processor unit belongs, the processor unit is configured to select a second port for transmitting the write data to the second storage system among the ports of the interface unit coupled to the controller to which the processor unit belongs, and to transmit the write data to the second storage system via the second port.