I have a fresh install of the Ubuntu 18.04 server image, on which I run
apt install ubuntu-desktop to get a desktop environment. No matter what I do, NetworkManager refuses to manage the ethernet device. I want this because I want to be able to manage my OpenVPN client from my desktop.
I've tried all the answers in both of these questions to no avail:
I've traced the problem to the file
/run/NetworkManager/conf.d/netplan.conf which contains the contents:
[keyfile] # devices managed by networkd unmanaged-devices+=interface-name:enp0s3,
If I remove the
unmanaged-devices line and restart NetworkManager then it works. But since
/run/ is a temporary filesystem, as soon as I reboot my changes are discarded.
I have no idea where this file is coming from, and my googlefu has failed me when it comes to figuring out how to get networkd to not take control of my ethernet port.