title: Docker image builds, but doesn't run
body: <p>I am trying to create a docker build for <a href="http://www.libreplan.com" rel="nofollow">libreplan</a>, using the install instructions <a href="http://www.libreplan.org/INSTALL.html#libreplan-manual-installation" rel="nofollow">here</a>.  The dockerfile is </p>
  
  <pre><code>FROM tomcat:6
  
  RUN apt-get -yq update &amp;&amp; apt-get -yq install \
    cutycapt \
    patch \
    postgresql-client \
    libpg-java \
    xvfb
  
  # Prepare webapp location
  RUN mkdir -p /usr/local/tomcat/webapps/libreplan
  # Get WAR file
  RUN wget -q -O /usr/local/tomcat/webapps/libreplan/libreplan.war http://downloads.sourceforge.net/project/libreplan/LibrePlan/libreplan_1.3.0.war
  # Install libreplan.xml
  ADD libreplan.xml /usr/local/tomcat/webapps/libreplan/libreplan.xml
  # Patch the policy to include libreplan
  ADD catalina.policy.patch catalina.policy.patch
  RUN patch -o /usr/local/tomcat/conf/catalina.policy /usr/local/tomcat/conf/catalina.policy catalina.policy.patch
  
  CMD ["catalina.sh", "run"]
  </code></pre>
  
  <p>The build works but doesn't do anything when I try to run it.  All the code is on <a href="https://github.com/aquavitae/docker-libreplan" rel="nofollow">github</a> and I have set up an automated build on the <a href="https://registry.hub.docker.com/u/aquavitae/libreplan/" rel="nofollow">docker registry</a>.  Included in the repo is a sample docker-compose.yml which should work, but when I try it no output is shown from the libreplan container and I can't access it through a browser.  I don't know tomcat at all so it is probably something that I have done wrong, but I don't know how to even start figuring out what.  Is there anything obvious that I have missed?</p>