How do I configure my DNS settings in Ubuntu server?

Question

According to this page it appears to be simple. However, /etc/bind does not exist on the default installation of Ubuntu 12.04.3 LTS server.

So, without installing any further software, how can configure DNS and remove dnsmasq on ubuntu server? I am quite familiar with sudo & nano.

Answer 1

Set DNS Servers

You need to configure the /etc/network/interfaces file if you want to change your DNS server via the command line.

It should look something like this:

# The loopback network interface  
auto lo  
iface lo inet loopback  


# The primary network interface  
auto eth0 
iface eth0 inet static  
address 192.168.X.X
netmask 255.255.255.0
gateway 192.168.X.X
dns-nameservers X.X.X.X 

If you have more than one DNS server, just add a space between each:

dns-nameservers X.X.X.X Y.Y.Y.Y Z.Z.Z.Z

Just replace the Xs, Ys, and Zs with your own IPs of the DNS servers of choice, and when this is done, run this command to update the settings:

sudo ifdown eth0 && sudo ifup eth0

Hope this helps!

Answer 2

Ubuntu 20.04 does not use resolv.conf anymore by default, however it can be installed by:

sudo apt install resolvconf

However if you are on some older Ubuntu version or some fork, you might be using resolvconf (a package that manages the contents of /etc/resolv.conf).

In order to set dns-nameservers which won't be removed after reboot add them in

sudo nano /etc/resolvconf/resolv.conf.d/base 

like

nameserver x.x.x.x
nameserver x.x.y.y

And afer that just do

sudo resolvconf -u

Answer 3

I use Ubuntu 20.04 and unfortunately non of the other answers worked for me.

So, I will share the way I fixed the problem below:

First install resolvconf, if it is not already installed

sudo apt update
sudo apt install resolvconf

check that resolvconf service is started and enabled

sudo systemctl status resolvconf.service

If service is not enabled, you can start and enable using the following commands:

sudo systemctl start resolvconf.service
sudo systemctl enable resolvconf.service

Now edit the resolv.conf.d/head configuration file

sudo nano /etc/resolvconf/resolv.conf.d/head

and add your DNS addresses into it (for example I use 8.8.8.8 and 8.8.4.4)

nameserver 8.8.8.8 
nameserver 8.8.4.4

Now force resolvconf to run update scripts when invoked with -u

sudo resolvconf --enable-updates 

Now run updates

sudo resolvconf -u

Now if you check the content of resolv.conf file using the following command

cat /etc/resolv.conf

you must see your DNS configuration. If not, try the following commands and check again

sudo systemctl restart resolvconf.service
sudo systemctl restart systemd-resolved.service

References:

https://www.tecmint.com/set-permanent-dns-nameservers-in-ubuntu-debian/ http://manpages.ubuntu.com/manpages/trusty/man8/resolvconf.8.html

Answer 4

As of 20.04 Focal Fossa, Ubuntu Server uses systemd-resolved to manage nameserver configuration. /etc/resolv.conf is a static file and should not be edited.

To configure your resolver, you set it in your netplan configuration file, like this:

network:
  version: 2
  renderer: networkd
  ethernets:
    enp0s25:
      addresses:
        - 192.168.0.100/24
      gateway4: 192.168.0.1
      nameservers:
          search: [mydomain, otherdomain]
          addresses: [1.1.1.1, 8.8.8.8, 4.4.4.4]

For more information on how to use the netplan system, see the Ubuntu article on network configuration.

Answer 5

NetworkManager TUI: nmtui

Beside this alternative using nmcli connection edit you might like a more ncurses approach with nmtui, the GNOME's CLITUI alternative to nm-connection-editor.

^{Note: This anwer is more related to Ubuntu Desktop, but since the suitable question was marked as duplicate of this one (incorrectly, IMO) I post it here.}