Warning
Use a sudo-capable account, keep shell history for audit, and back up critical paths before changing boot, SSH, or package state.
What you will achieve
Give servers and appliances stable IPs — netplan examples you can adapt.
1) Find interface and current config
ip -br a
ip route2) Configure netplan on Ubuntu 22.04/24.04
sudo nano /etc/netplan/01-static.yaml
sudo netplan try
sudo netplan apply3) Verify route and DNS
ip a
ip route
resolvectl status