ubuntu - Docker error : no space left on device

Question

I installed docker on a Debian 7 machine in the following way

$ echo deb http://get.docker.io/ubuntu docker main > /etc/apt/sources.list.d/docker.list
$ sudo apt-get update
$ curl -sSL https://get.docker.com/ubuntu/ | sudo sh

After that when I first tried creating an Image it failed with the following error

 time="2015-06-02T14:26:37-04:00" level=info msg="[8] System error: write /sys/fs/cgroup/docker/01f5670fbee1f6687f58f3a943b1e1bdaec2630197fa4da1b19cc3db7e3d3883/cgroup.procs: no space left on device"

Here is the docker info

Containers: 2
Images: 21
Storage Driver: aufs
Root Dir: /var/lib/docker/aufs
Backing Filesystem: extfs
Dirs: 25
Dirperm1 Supported: true
Execution Driver: native-0.2
Kernel Version: 3.16.0-0.bpo.4-amd64
Operating System: Debian GNU/Linux 7 (wheezy)
CPUs: 2
 Total Memory: 15.7 GiB


WARNING: No memory limit support
 WARNING: No swap limit support

How can I increase the memory? Where are the system configurations stored?

From Kal's suggestions:

When I got rid of all the images and containers it did free some space and the image build ran longer before failing with the same error. So the question is, which space is this referring to and how do I configure it?

Answer 1

The current best practice is:

docker system prune

Note the output from this command prior to accepting the consequences:

WARNING! This will remove:
  - all stopped containers
  - all networks not used by at least one container
  - all dangling images
  - all dangling build cache

Are you sure you want to continue? [y/N]

In other words, continuing with this command is permanent. Keep in mind that best practice is to treat stopped containers as ephemeral i.e. you should be designing your work with Docker to not keep these stopped containers around. You may want to consider using the --rm flag at runtime if you are not actively debugging your containers.

Make sure you read this answer, re: Volumes

You may also be interested in this answer, if docker system prune does not work for you.