How to Set DNS Server in Linux Ubuntu?

In the vast realm of Linux operating systems, Ubuntu stands as one of the most popular and user-friendly distributions. Configuring the Domain Name System (DNS) server settings on Ubuntu can be a crucial step for optimizing your internet connectivity and enhancing network performance. In this guide, we'll explore the step-by-step process of setting DNS servers on Ubuntu, ensuring a smooth and efficient browsing experience.

Checking Current DNS Settings:

Before diving into the DNS configuration, it's essential to check your current DNS settings. Open a terminal and use the following command:

nmcli dev show | grep 'IP4.DNS'

This command will display the current DNS server addresses configured on your system.

Setting DNS Servers Using Network Manager:

Ubuntu utilizes Network Manager for handling network-related settings, including DNS configurations. Follow these steps:

1. Open the terminal by pressing Ctrl + Alt + T.
2. Enter the following command to edit your connection settings:

sudo nano /etc/network/interfaces

3. Locate the line containing dns-nameservers and add your preferred DNS server addresses, separated by commas. For example:

dns-nameservers 8.8.8.8, 8.8.4.4

Replace the addresses with your desired DNS servers.

4. Save the changes and exit the text editor by pressing Ctrl + X, then Y to confirm, and finally Enter.

5. Restart your network manager with the following command:

sudo service network-manager restart

Setting DNS Servers Using systemd-resolved:

Ubuntu also employs systemd-resolved to manage DNS configurations. Here's how to set DNS servers using this service:

1. Open the terminal and edit the systemd-resolved configuration file:

sudo nano /etc/systemd/resolved.conf

2. Uncomment the line #DNS= by removing the # at the beginning and add your DNS server addresses:

DNS=8.8.8.8 8.8.4.4

Replace the addresses with your preferred DNS servers.

3. Save the changes and exit the text editor.

4. Restart systemd-resolved to apply the new settings:

sudo systemctl restart systemd-resolved

Verifying DNS Changes:

After making the changes, it's crucial to verify whether the new DNS servers are in effect. Use the following command to check the updated DNS settings:

systemd-resolve --status | grep 'DNS Servers'

This command will display the currently configured DNS servers.

Additional Tips:

• If you encounter any issues or want to revert to default settings, you can reset the DNS configuration. For Network Manager:

sudo nano /etc/network/interfaces

Remove or comment out the dns-nameservers line, save, and restart Network Manager.

For systemd-resolved:

sudo nano /etc/systemd/resolved.conf

Comment out the DNS line, save, and restart systemd-resolved.

Configuring DNS servers on Ubuntu is a fundamental aspect of optimizing your network connectivity. Whether you choose Network Manager or systemd-resolved, the process is relatively straightforward. By following the step-by-step instructions outlined in this guide, you can take control of your DNS settings and enjoy a faster and more reliable internet experience on your Ubuntu system.