I wanted test if is possible to create a docker container in a docker container recrusive.
Every used container is capable of running own docker containers. This sub container will run on the docker host of the first started container. All container are still running when started and start a new container. There is a counter implemented that count the started container instances.
!!! DANGER !!! This Docker file will work recrusive and can create very fast a lot of container from same image. In our test in 1 min 100 Docker Container can be created. There no direct way to stop the all containers because they are so many. Try in emergency STRG+C on Root Container or shutdown host
docker stop the-one
docker stop $(docker ps -a -q)
After this the docker daemon must be stopped, because the subcontainer are possible to contiune the creation without root.
sudo systemctl start docker
sudo service docker stop
docker build --tag=docker-recrusive-test .
And the simplest way is to just expose the Docker socket to your sub container, by bind-mounting it with the -v flag.
docker run --name=the-one -v /var/run/docker.sock:/var/run/docker.sock docker-recrusive-test