Docker container running tomcat - could not access the server using the host IP address

Question

I am trying to build a docker container running tomcat from a docker file. Please find below the Dockerfile content:

FROM ubuntu:trusty
MAINTAINER karthik.jayaraman
VOLUME ["/tomcat/files"]
ADD /files/tar/apache-tomcat-7.0.47.tar.gz /usr/local/tomcat
ADD /files/scripts/. /tmp/tomcat_temp
RUN ls /tmp/tomcat_temp
RUN cp  -a /tmp/tomcat_temp/. /etc/init.d
RUN chmod 755 /etc/init.d/tomcat
RUN chkconfig --add tomcat && chkconfig --level 234 tomcat on
ADD /files/config   /usr/local/tomcat/apache-tomcat-7.0.47/conf/
ADD /files/lib  /usr/local/tomcat/apache-tomcat-7.0.47/lib/
ENV CATALINA_HOME /usr/local/tomcat/apache-tomcat-7.0.47
ENV PATH $PATH:$CATALINA_HOME/bin
EXPOSE 8080
CMD ["service","tomcat","start"]

When i create the image and run a bash in the container, with the command "Service tomcat start", the server is started. I checked the catalina.out file and ensured that its running. But when i try the host IP on which docker is installed and access the port using the port number 8080, i could connect to tomcat page. But when i specify the internal IP address of the container - 172.24.0.7:8080, i could view the tomcat page. I guess the port forwarding is not properly. Can someone tell me the error i am making here.

Answer 1

Your docker container is running as long as last command is not done. You are booting up your tomcat as a daemon. This makes docker to stop running container as soon as tomcat is started.

You can changed your last line to:

CMD service tomcat start && tail -f /var/lib/tomcat/logs/catalina.out

Or just try using one of precreated tomcat containers from Docker Hub: https://registry.hub.docker.com/search?q=tomcat&s=downloads