Hi,

I have 3 TP-Link Deco XE75 routers at home, 2 of which are connected via Ethernet, and the third one is connected via 6Ghz Wi-Fi.

Today I wanted to connect the main router to a TP-Link TL-SG105 unmanaged switch as I ran out of Ethernet ports on the router.

However, all devices connected to the switch had no internet access. I suspected that maybe the port I connected to the switch to on the main router had something wrong with it (and I know for a fact it works fine as another device was connected to this port and had internet access), but switching to another port didn't help. I found this situation so strange that I suspected the main router might have an issue, so I made one of the other 2 routers the main one, but still that didn't help. I then suspected the switch might be defective, so I tried another TL-SG105 switch that was being used to connect devices (so I know for a fact it works) and it had the exact same issue.

There are many posts with people having issues connecting Deco routers to switches for Ethernet backhaul, but I'm not connecting multiple routers through the switch; I simply want to add extra Ethernet ports to my router for external network devices. Moreover, many answers suggest using TP-Link switches as they support iEEE 1905.1, which I'm doing already.

Does anyone have an idea why this is happening? Any help is appreciated!