I have built a base image from Dockerfile named centos+ssh. In centos+ssh's Dockerfile, I use CMD to run ssh service.
Then I want to build a image run other service named rabbitmq,the Dockerfile:
FROM centos+ssh
EXPOSE 22
EXPOSE 4149
CMD /opt/mq/sbin/rabbitmq-server start
To start rabbitmq container，run：
docker run -d -p 222:22 -p 4149:4149 rabbitmq
but ssh service doesn't work, it sense rabbitmq's Dockerfile CMD override centos's CMD.
Even though CMD is written down in the Dockerfile, it really is runtime information. Just like EXPOSE, but contrary to e.g. RUN and ADD. By this, I mean that you can override it later, in an extending Dockerfile, or simple in your run command, which is what you are experiencing. At all times, there can be only one CMD.
If you want to run multiple services, I indeed would use supervisor. You can make a supervisor configuration file for each service, ADD these in a directory, and run the supervisor with supervisord -c /etc/supervisor to point to a supervisor configuration file which loads all your services and looks like
[supervisord]
nodaemon=true
[include]
files = /etc/supervisor/conf.d/*.conf
If you would like more details, I wrote a blog on this subject here: http://blog.trifork.com/2014/03/11/using-supervisor-with-docker-to-manage-processes-supporting-image-inheritance/