Starting Docker as Daemon on Ubuntu

Have been using Docker successfully for a few weeks but today when I was following a set of instructions which suggested adding the following two lines to the docker configuration file at `/etc/init/docker.conf`: limit memlock unlimited unlimited limit nofile 262144 It then suggested restarting Docker with `sudo /etc/init.d/docker restart`. When I did this under Ubuntu 14.04 it reported back that: > * Docker is managed via upstart, try using service docker restart I tried `sudo service docker restart` to which it reported: > stop: Unknown job: docker > > start: Unknown job: docker Now I'm stuck with the docker daemon not running! I tried rebooting but it's still not running and when run something as simple as `sudo docker version` I get: Client version: 1.2.0 Client API version: 1.14 Go version (client): go1.3.1 Git commit (client): fa7b24f OS/Arch (client): linux/amd64 2014/10/01 09:57:45 Get http:///var/run/docker.sock/v1.14/version: dial unix /var/run/docker.sock: no such file or directory To troubleshoot I tried starting the docker daemon on the commandline with: sudo docker -d And in another terminal window I am now able to run Docker normally. That's great but HOW do I get it to startup normally again? Also I notice that I have TWO docker config files: /etc/init/docker.conf /etc/init/docker.io.conf They look like DUPs. Are they redundant? Which one should I be looking at? Do I need both? I also noticed that this duplicity shows up when I run `sudo service --status-all |grep docker` I get both `docker` and `docker.io` as listed services. Grown.