A request from one of our support technicians said
"Please exclude www.acompany.com:6969 from the proxy server.".
Note that it’s the :6969 which is important here. It tells the web browser to speak with the web site over port 6969 (normally this would be port 80).
"It’ll be blocked by our firewall", was my response to the request.
"but good luck with getting that port open.", I thought.
There are days when I think that when we were assigned the chimpanzees which run our network, we got the ones too dumb to peal their own bananas.
"How to tell though?", I thought
(whether port 6969 was open, not the intelligence of our chimps)
The answer was simple, firebind.com.
"Firebind provides a straightforward way to verify whether your application will be able to successfully communicate to its respective server via your Internet connection."
Firebind works, unlike port 6969: