How do I enter this dockerfile / nginx container?

Question

With centos in a docker container, I just type 'docker attach container ID' and it takes me to the shell prompt, where i can install and configure nginx.

This one is easier: docker.com dockerfile/nginx You just run the file and everything is installed and configured.

but i can't figure out how to get in and access the files.

Answer 1

In my case the standard bash didn't exist. Using /bin/sh helped me:

docker run -it -p 80:80 dockerfile/nginx /bin/sh 

Answer 2

UPDATE (a much easier method that was introduced later):

docker exec -t -i container_name /bin/bash 

Original answer

Actually you can access a running container too.

Find your container's ID:

docker ps 

Export the ID of the process that runs the container:

PID=$(docker inspect --format '{{.State.Pid}}' my_container_id) 

"Connect" to it by changing namespaces:

nsenter --target $PID --mount --uts --ipc --net --pid 

Originally this was described here: http://jpetazzo.github.io/2014/03/23/lxc-attach-nsinit-nsenter-docker-0-9/