Docker How To Map Ports To Tomcat Application Server

How to map ports to your Tomcat application server in Docker.
Example uses Tomcat 7.
Adapt to your tomcat directory if using another version.

In Dockerfile:

#start Tomcat and map Port 8080 to Container Port 8080
RUN sed -i 's/port="8080"/port="8080"/' /opt/apache/tomcat/conf/server.xml

URL: http://localhost:8080



Example 8081:

#start Tomcat and map Port 8080 to Container Port 8081

RUN sed -i 's/port="8080"/port="8081"/' /opt/apache/tomcat/conf/server.xml

URL: http://localhost:8081

How to make Virtualbox available on Windows via localhost

Sometimes fate forces us to work with Windows.
Because Linux is so good, we get a VirtualBox to emulate it.

How can we access a webapplication via localhost:8080 from the Windows machine inside of a Webbrowser?

VirtualBox Manager -> VM-Tools -> Settings -> Network -> Port Forwarding

Name: http8080 
Protocol: TCP
HostIP: empty
Host-Port: 8080
Guest-IP: empty
Guest-Port: 8080


Name: ssh 
Protocol: TCP
HostIP: 127.0.0.1
Host-Port: 2222
Guest-IP: empty
Guest-Port: 22