This problem can be detected by checking whether the light port is on, then checking whether the light module parameters such as wavelength, speed and transmission distance match, and then checking whether the gateway is configured and whether the VLAN is the same. This document describes how to check the switch interface or port status and how to locate an interface physically down fault and restore the interface to the up state. Hardware failures: include hardware. Problem: All optical ports cannot be connected, and the indicator lights are not on. During use, reading optical module information helps understand its real-time operating status, enabling faster troubleshooting of link abnormalities.