Today I plug the cable to WAN (from another router) and at first I was able to get internet. After about 5 mins, I found there is no internet connection. I have since tried unplug and replug, reboot, and even press the reset button. Nothing seems to work. In the end, I just use the wireless bridge and connect to the wifi of the other router. I tested the other router’s lan to make sure it is working. So it looks like something is wrong with the GL-SF1200’s WAN?
You can make a final attempt to update the firmware using uboot. If the problem persists, please contact the after-sales service.