riak - Run a service automatically in a docker container

Question

I'm setting up a simple image: one that holds Riak (a NoSQL database). The image starts the Riak service with riak start as a CMD. Now, if I run it as a daemon with docker run -d quintenk/riak-dev, it does start the Riak process (I can see that in the logs). However, it closes automatically after a few seconds. If I run it using docker run -i -t quintenk/riak-dev /bin/bash the riak process is not started (UPDATE: see answers for an explanation for this). In fact, no services are running at all. I can start it manually using the terminal, but I would like Riak to start automatically. I figure this behavior would occur for other services as well, Riak is just an example.

So, running/restarting the container should automatically start Riak. What is the correct approach of setting this up?

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For reference, here is the Dockerfile with which the image can be created (UPDATE: altered using the chosen answer):

FROM ubuntu:12.04
RUN apt-get update
RUN apt-get install -y openssh-server curl 
RUN curl http://apt.basho.com/gpg/basho.apt.key | apt-key add -
RUN bash -c "echo deb http://apt.basho.com precise main > /etc/apt/sources.list.d/basho.list"
RUN apt-get update
RUN apt-get -y install riak
RUN perl -p -i -e 's/(?<={http,s[s{")127.0.0.1/0.0.0.0/g' /etc/riak/app.config
EXPOSE 8098 
CMD /bin/riak start && tail -F /var/log/riak/erlang.log.1

EDIT: -f changed to -F in CMD in accordance to sesm his remark

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MY OWN ANSWER

After working with Docker for some time I picked up the habit of using supervisord to tun my processes. If you would like example code for that, check out https://github.com/Krijger/docker-cookbooks. I use my supervisor image as a base for all my other images. I blogged on using supervisor here.

question from:https://stackoverflow.com/questions/17252356/run-a-service-automatically-in-a-docker-container

Answer 1

To keep docker containers running, you need to keep a process active in the foreground.

So you could probably replace that last line in your Dockerfile with

CMD /bin/riak console

Or even

CMD /bin/riak start && tail -F /var/log/riak/erlang.log.1

Note that you can't have multiple lines of CMD statements, only the last one gets run.