follow these steps to add a failover IP address: Firstly go to your server and connect it by SSH then run the following command: vi /etc/netplan/50-cloud-init.yaml Use the editor to edit Ubuntu Network file. For example Nano text editor. After that, edit the file  replacing INTERFACE_NAME MAC_ADDRESS and FAILOVER_IP Then save and close your file. Test the configuration. By running the following command: netplan apply