To add a new IP address to your Ubuntu server, follow these steps:

1. Identify Your Network Interface:

   • Determine if your main network interface is eth0 or eth1 by running:

     grep eth1 /etc/netplan/* -H
     

   • Replace eth1 with eth0 if necessary and note the result.

2. Edit the Netplan Configuration File:

   • Once you know your interface (e.g., eth0), open the corresponding netplan file using a text editor:

     sudo nano /etc/netplan/50-netplan.conf
     

   • Locate or create the section for your interface, typically under [eth0].

3. Add Your IP Address:

   • Copy the provided IP address in the format AA.BB.CC.DD/XX (e.g., 192.168.1.1/24) and include it under the appropriate configuration:

     network: eth0: set physical set address XX.XX.XX.XX/YY

4. Apply Changes:

   • Apply the updated configuration with:

     sudo netplan apply
     

   • Open a new terminal and test the IP by pinging it:

     ping 192.168.1.1
     

5. Troubleshooting:

   • If the ping fails, wait up to 30 seconds for netplan to revert changes if necessary.
   • Ensure correct syntax and permissions in the netplan file.