Charles, I have the Pace gateway also. In the Firewall application, pinholes and DMZ tab, have you also done the following:
In Section 1, have you selected the IP address of the computer hosting your Roon Core? In my case, I have a second router attached to my Pace gateway (for providing improved WiFi and other capabilites), and this is the device I have selected here. In your case, this should be your Orbi router.
In Section 2, Edit firewall settings for this computer, have you selected:
Allow individual application(s) →
User-defined →
Select your port forwarding rule under “Application List” →
“Add” →
and the port forwarding rule should be in the Hosted Applications list
If your Orbi also is acting as a router, then you need to also configure the main Orbi router with the identical TCP/UDP port forwarding rule as for the Pace gatewat
One area to note: if your Orbi is in bridge mode and all routing and DHCP functions are performed by the Pace gateway, and Step 3 above does not allow ARC to connect, you may need to put the IP address of your Roon Core computer in Step 1 in place of the Orbi router
OK, I tried, one at a time, removing each exception when it didn’t work: the IP of the Orbi router, the IP of the satellite, and the IP of the MacBook that is the core, none worked. I used the range 55009 to 55002 and forwarded to port 55002 which is hard coded in Roon. No sure how to edit bridge mode, don’t see that in the Orbi interface
If you’re getting into the ATT interface there is a chance that the modem/router isn’t in bridge mode. With the employment of a mesh system like orbi or eero, the modem should be in bridge mode. This allows for the Orbi setup to manage the network instead of both of them bumping heads in trying to do so.
@Jim_F is correct. You need to create a User-Defined rule for port forwarding on the Pace and match that with the same port forwarding rule on your Orbi router. The Pace then needs to enable the port forwarding rule by referencing the Orbi router in the Pinhole, DMZ settings section on the Pace.