After I upgraded a PC with 18.04 Ubuntu to 20.04 my wifi won’t work. After some troubleshooting, I have found that if I have an ethernet cable plugged into the network the wifi says it can’t find an adapter, but if you unplug the network cable the wifi comes on and you can pick any SSID that is listed and seems to work as it should. If you plug in the network cable again the wifi shuts off again. Can someone explain why after the upgrade the wifi would work like this?
I can only assume that there is an adapter priority as a feature. Meaning, if you plug in the Ethernet cable, the priorized adapter is the Ethernet adapter (which is just logical and totally reasonable). There is absolutely no reason to use the WiFi if you have a working internet connection over Ethernet. That’s why it probably disabled WiFi when an Ethernet cable is connected.
I recommend keeping this feature turned on, due to aforementioned reasons.
I just wanted to make sure there isn’t something wrong and it was intended to be this way. I like the idea but my users are going to ask about why they don’t have wifi at the same time.
I think the problem is solved by explaining that an internet connection over cable will always be better than a connection over wave signals.
A post was split to a new topic: Lost Wi-Fi after upgrade to Ubuntu 20.04
There seems to be a problem with Ubuntu and Wifi sometimes. My own story. I D/L’ed both Ubuntu and Xubuntu 20.04 and installed both on the same laptop. Ubuntu worked fine with Wifi, but Xubuntu would only work with the Ethernet cable. I could not get the Wifi to work. A week / 10 days later, I D/L another copy of Xubuntu, installed it, and it works fine with wifi. Of course, I don’t know what fixes the wifi. The reload or the second copy of Xubuntu.