Docker inside Docker (without command line)

Question

I want to run docker daemon inside my docker image. I know I can easily achieve this by exposing outer docker process during running my docker image, but unfortunately I have no possibility to control how my image is run. I CAN NOT use DIND.

Therefore I would like to start docker service inside either Dockerfile or some script that is my entrypoint. I tried invoking command:

CMD service docker start

after downloading and installing docker in the image and also including this command in some script start.sh and calling it:

ENRYPOINT ["path/to/script/start.sh"]

None of this worked. Is it at all possible to run docker as I want or am I doing something incorrectly or it is just not possible in my execution environment?

score 1 · Accepted Answer · answered Jul 23 '16 at 20:19

1

Per your requirements, you can't.

To run the docker service inside of a docker container, you need to modify how the container is launched to give the inner docker service privileges the outer docker service restricts by default.

answered Jul 23 '16 at 20:19

BMitch

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Ok, thanks. I was afraid that it can be impossible. Thanks! – Jakub Nowak Jul 23 '16 at 23:00

score 0 · Answer 2 · answered Jul 23 '16 at 11:50

0

I would suggest to use the DIND Container (Docker in Docker)

docker run --privileged --name some-docker -d docker:1.8-dind

Link to Docker Hub: https://hub.docker.com/_/docker/

answered Jul 23 '16 at 11:50

opHASnoNAME

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I said I am not able to configure the way of running the container so I can't use DIND. – Jakub Nowak Jul 23 '16 at 14:27

Docker inside Docker (without command line)

2 Answers2