Roon ARC will not connect (UDMP w/ AT&T Gigabit Internet)

[Rugby (aka Daniel or Big Dan)]

Hi Preston,

Sorry to hear about your issues getting ARC connected. Have you had a read of this thread which might help you get things sorted?

Ubiquiti UniFi Dream Machine UDM-US with Zyxel C3510XZ Modem/Router (Gateway) [Solution Edited into Post - Please Read OP's Full Post]

Following Roon’s documentation for router configuration, I was unsuccessful enabling ARC to connect to Roon Core. It turned out I needed a “Modem Port Forwarding rule”, which is outlined below. NOTE: One of the first tests I did was to connect my NUC (Roon Core) directly to my Zyxel Modem and see if Roon ARC could connect to Roon Core. This test was successful, leading me to believe there was a configuration that will work, even though I was getting an error after configuring UPnP and Port Forw…