Configure a static IP address, subnet mask, gateway, and DNS server in Ubuntu.

Problem Statement:-

Configure a static IP address, subnet mask, gateway, and DNS server for a network interface using the command line. Verify that the network configuration persists after rebooting the system.

Solution:

First of all, I must remove all your confusion:

Earlier in Ubuntu, when we want to change the IP address we use /etc/network/interfaces        

This file is used by “ifupdown” tools from Debian. Now Ubuntu has switched from “ifupdown” to “Netplan”.

So now your network settings are handled from /etc/netplan/? in this folder you will get a ‘.yaml’ file.

Now talk about the solution:

• Go to /etc/netplan here you get a YAML file, as you can see below -

• In this file you see renderer, if it is set to ‘NetworkManager’, it means your Ubuntu system Network configuration is managed by GUI Network Manager.
• But we want to do it on the command line. For this set rendered to networkd and define interface information like IP address, subnet mask, gateway, and DNS like the below screenshot.

• Now save the file and run sudo netplan apply
• Now your changes will persist across reboots.

Now if you made any mistake or want to get back the old stat of network configuration as it was.

Then do this:

• Change renderer back to ‘NetworkManager’ and also erase the interface information that you gave.
• Now your .yaml file should look like this-

• Save it and run “sudo netplan apply”
• Now restart the system and your network will work fine.

Now hope you understand the whole process and if you have any suggestions DM me.

Thank you for reading.