I have a blank site running in IIS, bound to port 80 HTTP traffic. This sits behind a router that port-forwards HTTP traffic to my server. Publicly I have a domain registered and use FreeDNS.Afraid.org as my dynamic DNS provider to point at my router. This is working, I can see my site publicly.
Also on my router, I am port-forwarding Plex's assigned port to the same port on my server. This is also working, I can manually find the Plex web page via mydomain.com:<plex port>/web.
I have a sub-domain registered that is in the format plex.mydomain.com where my regular domain is www.mydomain.com. On FreeDNS I can successfully point plex.mydomain.com to my blank web page.
What I am trying to do is have IIS listen for requests to plex.mydomain.com and route them to either localhost:<plex port>/web or mydomain.com:<plex port>/web.
I installed the URL Rewrite module and created a standard rule for redirecting based on matches with the word "plex" in it, this didn't work. I attempted to log what was happening using Failed Request Tracing; I got log files but they didn't mention any attempts to rewrite the URL.
I installed Application Request Routing, but this won't let me specify a port number. I have yet to try adding a new application to IIS that represents the Plex server.
How can I route requests to plex.mydomain.com to mydomain.com:<plex port>/web?
I haven't got access to my server currently (but can provide the URL Rewrite configuration if necessary). Also, my experience with IIS and deployment is limited so pardon any contradictions I've made, if any.
I believe this is IIS Express on Windows 8 Pro.