External access via UAG only shows gray page, no login form, just CS Favicon
Hey there, kind folks!
I'm having problems accessing my Horizon HTML portal page externally via UAG.
Internally, when connecting via Windows VM (it's in the same network as the UAG) it works just fine. I can access the Admin interface, and as a user I'm being re-directed to the HTML interface of the Connection Server this UAG instance is married to (as intended). Also, all VM operations within vCenter work as expected. All good here.
Externally, on the other hand, this solution is integrated into a security portal governed by an external IT organization. You have to login to a web portal first, there shortcuts are set up that should open up the connection to the VDI Desktop(s) by pointing to the same UAG user facing page. Therefore what I expect to see: The HTML portal of the connection server, right?
What I see is only (!) the Favicon but other than that only a gray page with no login forms and no further information whatsoever.
Does anyone have an idea, what the problem could be? Seeing the Favicon speaks for the fact I'm already past the UAG and that the Connection Server is the culprit actually blocking the connection. It's totally unclear to me whether there's extended logging functionality where I can find the reason for this or if anyone else has an idea why it happened etc. - no further idea(s).
To anyone interested I am pretty sure I found the reason for the login page not showing.
First you login to some FortiGate web component providing an initial login page where you have to type in AD credentials and where you're being asked for 2FA (SMS code). Once entered, you'll be re-directed to a portal page where you can place shortcuts to internal resources, such as the Horizon UAG.
I re-formatted the original CS welcome webpage to display it more clearly and here's what the gray page's source code looks like:
This will now have to be discussed with Fortinet as an update might have already solved the issue. That means that the provider of this initial web portal might have to update some components first. AAAAAAAAAAAAAAAAAAAAAAAARGH!