Restarting Docker


I am trying to restart docker in a build and with the following. I am trying to adjust the docker storage to support a larger image.

echo 'DOCKER_OPTS="-s devicemapper --storage-opt dm.basesize=30G"' | sudo tee /etc/default/docker > /dev/null
sudo service docker restart

I try running docker info and get the following.

docker info
Cannot connect to the Docker daemon. Is the docker daemon running on this host?

docker info returned exit code 1

Action failed: docker info

The build output is here,

I am trying to run Cloud Foundry through a Docker container,

Any idea on what is going on?


I ran a fork of your build via SSH.

Looking in the Docker daemon logs (/var/log/upstart/docker.log) I see:

INFO[0000] API listen on /var/run/docker.sock
FATA[0000] Error starting daemon: error initializing graphdriver: driver not supported

This happens right after Docker starts which explains why docker restart works, but then docker info fails right afterwards. If you were to run service docker status you would see that it is actually not running.

I’ve never seen this specific error message before, but on thing to keep in mind is that we are running a fork of Docker in an unprivileged LXC container which may limit some of the things that you are able to do. Specifically it looks like we do not support editing devicemapper right now.


I was thinking about this more. The Docker fork explains why you can’t do this, but I am curious why you need to at all. We do not impose any limits on the disk size per se, is this a docker limitation? Do you have a link to a build where it complains about the size of the image?