a plurality of CPU module units, each of the plurality of CPU module units being provided with at least one I/O adapter and a processor;

at least one I/O switch module unit which has a plurality of Ethernet interface controllers, and connects each said at least one I/O adapter of each of said plurality of CPU module units to one of said plurality of Ethernet interface controllers via an I/O switch;

at least one Ethernet switch module unit which is provided with a plurality of internal ports and a plurality of external ports wherein each of the plurality of internal ports is connected with each of the plurality of Ethernet interface controllers of said at least one I/O switch module unit via Ethernet, and wherein each of the plurality of external ports is connected to an external network; and

at least one management module unit which is connected to said plurality of CPU module units, said at least one I/O switch module unit, and said at least one Ethernet switch module unit, and performs management of said plurality of CPU module units,

wherein said at least one management module unit performs control of said at least one I/O switch module unit to be capable of changing a number of said plurality of Ethernet interface controllers to be allocated to each of said plurality of CPU module units,

wherein said at least one management module unit has network configuration information showing a correspondence relationship between each of the plurality of Ethernet interface controllers of each of said plurality of CPU module units and a corresponding internal port of the plurality of internal ports, and of the at least one Ethernet switch module unit,

wherein each of said plurality of CPU module units has a device driver which sets at least one said plurality of Ethernet interface controllers on a corresponding CPU module unit of the plurality of CPU module units, and a management agent unit performing setting of the device driver into said at least one Ethernet interface controller through communication with a management terminal which is externally connected to said composite computer apparatus for performing management of said composite computer apparatus,

wherein when network setting is performed to one of the plurality of Ethernet interface controllers through the communication with said management terminal, said corresponding CPU module unit performs network setting of the one of the plurality of Ethernet interface controllers of said corresponding CPU module unit to said management agent unit operating on said corresponding CPU module unit through the communication with said management terminal at a time of the setting of the corresponding internal port of the at least one Ethernet switch module unit connected to said one of the plurality of Ethernet interface controllers,

wherein said management agent unit performs setting to the device driver of the one of the plurality of Ethernet interface controllers of said corresponding CPU module unit and creates network setting information required for the corresponding internal port of the at least one Ethernet switch module unit connected to the one of the plurality of Ethernet interface controllers of said corresponding CPU module unit to notify the network setting information to said at least one management module unit, and

wherein said at least one management module unit identifies one internal port of the plurality of internal ports, and of the at least one Ethernet switch module unit to be set from said network configuration information to perform network setting in accordance with said network setting information to the identified one of the internal ports of the plurality of internal ports, and of said at least one Ethernet switch module unit.