Updating resolv.conf on Linux with Google DNS

The resolv.conf file is a vital component on Linux systems that specifies the DNS servers used to resolve domain names into IP addresses. Sometimes you need to update this file to use reliable DNS servers, such as Google’s. This step‑by‑step guide shows how to do it safely.

First, check if systemd-resolved is active

systemd-resolved is a DNS resolver service provided by systemd, commonly used in modern Linux distributions. Before changing resolv.conf, ensure that systemd-resolved is in use to keep DNS settings compatible and working.

Check its status:

sudo systemctl status systemd-resolved

If the service is active and running, you’ll see output indicating “active (running)”. If not, enable and start it:

sudo systemctl enable systemd-resolved
sudo systemctl start systemd-resolved

Step 1: Open resolv.conf

Open the file with your preferred editor (Vim, Nano, Gedit, etc.):

sudo vim /etc/resolv.conf

Step 2: Make the changes

Replace the current nameservers with Google’s DNS servers:

nameserver 8.8.8.8
nameserver 8.8.4.4

Step 3: Save and close the file

In Vim, press Esc, then type :wq and press Enter. Follow your editor’s instructions otherwise.

Step 4: Verify the changes

Use cat to confirm the new configuration:

cat /etc/resolv.conf

You should see the new Google DNS servers listed.

Conclusion

Updating resolv.conf on Linux to use Google’s DNS servers is simple and helps ensure fast, reliable name resolution. By following this guide, you can configure your system with confidence.