Comment 7 for bug 1821867

This seems quite likely to be an issue with netplan; I've had a similar report on UC18; where systemd-networkd isn't started.

Turns out netplan moved the enablement of systemd-netwrokd to network-online.target; but unfortunately there may be no service or target depending on that. I'll revert the change to put systemd-networkd back under multi-user.target.