title: Symlink command in Dockerfile doesn't create the link in the container
body: <p>In my Dockerfile I have this line:</p>
  <p><code>RUN ln -s /var/www/html/some_file /var/www/html/another_file</code></p>
  <p>When running docker build all the steps are executed including the creation of the symbolic link, but when I start a container using the image created and check the folder <code>/var/www/html/</code> I don't see the link there.
  I tried searching online if this is something supported by docker and couldn't find an answer.
  The content of the container is already available by another container image I am using with the <code>FROM</code> instruction, so the file <code>/var/www/html/some_file</code> is not on my machine.</p>
  <p>No Volumes are involved. This is the Dockerfile:</p>
  <pre><code>FROM piwik:3.2.1-apache
  
  RUN apt update
  
  RUN ln -s /var/www/html/some_file /var/www/html/another_file
  
  CMD [ &quot;apache2-foreground&quot; ]
  </code></pre>