Due to the unstable external power supply, power line aging or lightning strikes, etc., the power supply is damaged, the fan is stagnant, or other internal components are damaged, which affects the normal operation of the switch. If the POWER indicator light on the panel is green, it indicates that it is normal; if the indicator light is off, it means that the switch is not supplying power normally. Such problems are easy to detect, easy to solve, and the easiest to prevent. For such failures, the first thing to do is to supply external power, generally by introducing an independent power line to supply an independent power supply, and adding a voltage regulator to avoid instantaneous high or low voltage phenomena. If conditions permit, you can add UPS (uninterruptible power supply) to ensure the normal power supply of the switch. Some UPS supply voltage stabilization effect, while others do not. Pay attention when choosing. Set up professional lightning protection methods in the computer room to avoid lightning damage to the switch. Now there are many professional companies doing lightning protection engineering, which can be considered when performing network wiring.