This container runs systemd and does nothing else.

You can:

1. Start it with docker run --privileged -d -v /sys/fs/cgroup:/sys/fs/cgroup:ro rasschaert/systemd_centos7
2. Create a bash session with nsenter
3. install, configure and start another service
4. Create a more useful image with docker commit.

All credit for getting this to work goes to Dan Walsh, you can read more about it on his blog.

Motiejus Jakštys has made a very similar container image that also spawns a bash shell immediatly in the foreground.

I prefer my approach, with nsenter, at least until docker implements a similar mechanism.