@zoltan-sule, can you add the results of running:
$ ls -l /etc/resolv.conf $ cat /etc/resolv.conf $ systemd-resolve --status $ grep . /run/resolvconf/interface/* -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to resolvconf in Ubuntu. https://bugs.launchpad.net/bugs/1816530 Title: DNS servers are not being set in the system correctly when you upgrade from 16.04 to 18.04 Status in resolvconf package in Ubuntu: New Bug description: I upgraded my 16.04 to 18.04 before the official release. After the upgrade I noticed that I don't have internet access. The wired network and the wifi settings looked good, but the internet didn't work. After the login the system always switched itself into airplane mode. I tethered the network via USB and Bluetooth by my mobile but they also didn't work. I found a useful answer from @andrew-woodhead666: https://answers.launchpad.net/ubuntu/+question/665374 it seems this bug is still not fixed for the upgraded dists in the main release and affects a few dozens of ubuntu users. https://askubuntu.com/questions/1021884/no-internet-after-upgrade-from-16-04-to-18-04 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/resolvconf/+bug/1816530/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
