How do I manually configure DNS name resolution on Ubuntu 16.04?

Question

I'm relatively new to Ubuntu, having previously used Debian and Red-Hat based distros. I'm trying to configure my Ubuntu 16.04 (KDE) desktop's DNS settings. The machine is running a DHCP client but I want to manually configure DNS different to the DHCP setting to allow me to point my DNS at a separate nameserver. The file /etc/resolv.conf contains:

nameserver 127.0.1.1

As I understand it, this is pointing to a local dnsmasq instance. I've read elsewhere that this can be disabled by commenting out the "dns=dnsmasq" setting in /etc/NetworkManager/NetworkManager.conf. I tried this and then manually edited resolv.conf. All seemed well until I rebooted, then resolv.conf pointed back to 127.0.1.1 and DNS no longer worked.

As background to why I'm doing this: I'm trying out a Samba 4 AD Domain Controller with SSSD on the Ubuntu client so the client must use the Samba machine's DNS, but I don't want to change my DHCP settings to point all clients at the Domain Controller.

Answer 1

I think you should make changes to interfaces file instead of NetworkManager.conf file. Add dns-nameservers to interfaces file. location of interfaces file should be /etc/network/interfaces

I hope this should resolve your issue. If it does not, then post the contents of both the files here.