Disable Docker autostart at boot?

Question

I was trying to experiment with docker, Ubuntu 14.04, 64-bit. I managed to run an image, and I gave it the path on one of my removable drives, /media/Drive1.

Now, whenever I reboot, I see there is a /media/Drive1 with only a docker directory inside it, and the actual drive which should be Drive1 ends up mounted on /media/Drive11, and this happens every reboot - even when I unmount these drives, and do a sudo rm -rfv /media/Drive1 before rebooting!

So something probably creates /media/Drive1 before it is fully mounted, and I guess that something is docker, because when I boot, I have:

$ ps axf | grep docker
 2085 ?        Ssl    0:00 /usr/bin/docker -d

So, how can I disable the docker autostart, so it doesn't interfere with the mounting of external USB drives at boot?

Answer 1

On the systems since Ubuntu 16.04+ (where OS uses systemd), according to the doc, autostart on boot can be turned off by:

$ sudo systemctl disable docker.service
$ sudo systemctl disable docker.socket

or as @Burak said in the comment, here is the one liner command:

sudo systemctl disable docker.service docker.socket

Note that if you do not disable the socket as well as the service then the service will get started anyways as the socket depends on it.

Answer 2

Ok, I think I managed to get it working, following How to enable or disable services?:

sudo bash -c 'echo manual | sudo tee /etc/init/docker.override'

Hope that was it...

Answer 3

I think the best way is to apply mask to the service:

sudo systemctl mask docker