Network system, method, and switch device

A method executed in a network system including a plurality of switch devices and an information processing device, the plurality of switch devices including a first switch device and a second switch device, the method comprising:

• when a failure occurring at a first port of a first plurality of ports in the first switch device, detecting the failure by a first processor of the first switch device;
• generating, by the first processor of the first switch device, failure information of the first port;
• transmitting, by the first processor of the first switch device, a failure notification packet including the failure information to other switch devices of the plurality of switch devices through the first plurality of ports other than the first port;
• receiving, by a second processor of the second switch device, the failure notification packet through a second port among a second plurality of ports,
• adding, by the second processor, selection condition information to the failure notification packet to generate a selection-condition-added packet,
• transmitting, by the second processor, the selection-condition-added packet through a port among a second plurality of ports which is coupled to the information processing device, the selection condition information indicating a selection condition that the second port that receives the failure notification packet is selected as a port to relay a packet;
• receiving the selection-condition-added packet by a third processor of the information processing device,
• extracting, by the third processor, the failure information and the selection condition information from the selection-condition-added packet,
• storing, by the third processor, the selection condition information and selection condition information into a first memory in the information processing device;
• and
• performing, by the third processor, a path control of a packet based on the selection condition information in the first memory.