<p>I'm attempting to create an FTP service with Kubernetes via google cloud. I've created the docker image with and exposed the necessary ports with: <code>EXPOSE 20 21 50000-52000</code>.</p>

<p>I've run into several problems so far: The biggest involving port ranges. ProFTPD needs a good amount of ports available to be able to handle passive connections, so I'm not quite sure how to create a service that will allow this.</p>

<p>This lead me to <a href="https://stackoverflow.com/questions/35603658/configure-port-range-mapping-into-containers-yaml-for-google-container-engine">this issue</a> which mentions I should use the <code>hostNetwork: true</code>, but that doesn't help the fact that each service needs to have well defined ports. After some configuration changes, I was able to add the 2000 ports by defining them out manually. When I did this though, now google API returns an error when trying to create the load balancer because it only allows 100 ports in the array (But it does appear via the console they support ranges).</p>

<p>How do I go about adding this FTP service, and supporting the passive range?</p>

<p>Kubernetes does not currently support port ranges.  It's difficult to implement with the legacy (but still supported) userspace proxy.</p>

<p>I think there are a few GH issues open on this but <a href="https://github.com/kubernetes/kubernetes/issues/20420" rel="nofollow">https://github.com/kubernetes/kubernetes/issues/20420</a> is one.</p>
