Sounds like lxc-docker.service simply wasn't enabled. "enabling" is basically creating a symlink from multi-user.target.wants to lxc-docker.service. This is don

Sounds like lxc-docker.service simply wasn't enabled. "enabling" is basically creating a symlink from multi-user.target.wants to lxc-docker.service. This is done by 'systemctl enable lxc-docker.service' once that service declares WantedBy=multi-user.target in its [Install] section. Other symptoms that would indicate this was the problem would have been that 'systemctl status lxc-docker.serivce' would have said "Loaded: loaded (...; disabled)" and "Active: inactive (dead)". i.e., systemd never started the service because nothing ever wanted it.