How to keep Docker container running after startin

Question

I've seen a bunch of tutorials that seem do the same thing I'm trying to do, but for some reason my Docker containers exit. Basically, I'm setting up a web-server and a few daemons inside a Docker container. I do the final parts of this through a bash script called run-all.sh that I run through CMD in my Dockerfile. run-all.sh looks like this:

service supervisor start
service nginx start

And I start it inside of my Dockerfile as follows:

CMD ["sh", "/root/credentialize_and_run.sh"]

I can see that the services all start up correctly when I run things manually (i.e. getting on to the image with -i -t /bin/bash), and everything looks like it runs correctly when I run the image, but it exits once it finishes starting up my processes. I'd like the processes to run indefinitely, and as far as I understand, the container has to keep running for this to happen. Nevertheless, when I run docker ps -a, I see:

➜  docker_test  docker ps -a
CONTAINER ID        IMAGE                            COMMAND                CREATED             STATUS                      PORTS               NAMES
c7706edc4189        some_name/some_repo:blah   "sh /root/run-all.sh   8 minutes ago       Exited (0) 8 minutes ago                        grave_jones

What gives? Why is it exiting? I know I could just put a while loop at the end of my bash script to keep it up, but what's the right way to keep it from exiting?

Answer 1

you can run plain cat without any arguments as mentioned by bro @Sa'ad to simply keep the container working [actually doing nothing but waiting for user input] (Jenkins' Docker plugin does the same thing)