Also... did you know you can now install ALL of Openstack into a single LXC container. Each of the Openstack "services" (nova, swift etc) are then all installed into "nested" lxc containers inside the "master/parent" container.
Takes a while to install everything but when done you have a nice testing OpenStack environment on your laptop or desktop to experiment with.
If you want to stop OpenStack you just lxc-stop the master/parent container same to restart Openstack.