When I connect to a network (e.g. home or work network), I have to manually enter the nameserver adresses in /etc/resolv.conf every time (I change to a new network). It used to be automatic. Any ideas how to change this back to automatic again ?
/etc/resolv.conf shoud be symbolic link to /run/resolvconf/resolv.conf file which is updated automatically by resolvconf program when network configuration changes. Probably your /etc/resolv.conf is a separate file. Just check it with:
ls -l /etc/resolv.conf
Rename or delete this file and make a symbolic link to /run/resolvconf/resolv.conf
ln -s /etc/resolvconf/resolv.conf /etc/resolv.conf
Change Default DNS 127.0.0.53 To your NEW DNS (Changes the default DNS automatically on reboot) In Terminal:
sudo rm -f /etc/resolv.conf sudo ln -s /run/systemd/resolve/resolv.conf /etc/resolv.conf sudo reboot