An information processing system includes a plurality of control apparatuses communicably coupled to each other. A first control apparatus of the plurality of control apparatuses includes a first memory configured to store first instructions and a first processor configured to operate using standby power before a power-on selection is made. The first processor executes the first instructions causing a process including collecting first identification information of each of the plurality of control apparatuses other than the first control apparatus. The process includes storing the first identification information in the first memory. The process includes determining a role of the first control apparatus based on a comparison result derived by comparing second identification information of the first control apparatus with the first identification information.