title: Linking exposed port of docker with with the default nginx port
body: <p>I have this Dockerfile:</p>
  
  <pre><code>FROM alpine:3.4
  RUN apk update
  RUN apk add nginx 
  RUN apk update
  RUN cp index.html /var/lib/nginx/html/
  EXPOSE 8080    
  </code></pre>
  
  <p>Now, how can I access the file index.html on lets say port 9000 on localhost? I got puzzled. Please ask if I am not clear. Just an outline to solution is highly appreciated.</p>