Thanks, @Axel_Lesch. I’ve just had a chat with my ISP, BT, and they’ve said that they provide Public IP address to all their residential customers (of whom I am one).
WRT the two routers, both the BT Hub and the Asus ZenWiFi have DHCP servers enabled. Should I disable the DHCP server on the BT Hub (all the wifi is dealt with via the ZenWifi)?
I am using Zenwifi AX, I have the same problem that Roon ARC is not able to connect to the Core. I have tried all the tips mentioned above, did I miss any :
NAT Type change to Fullcone,
Manual input the port forwarding with both external port and internal port put 55002, use protocol both and TCP
Something strange has happened. Must be the result of me changing various settings. Now when I try to assign Roon’s user defined IP address, I get a message saying “The host does not belong to any recognized LAN.”
@Philip_Gibson
Are you possibly able to restore from memory your previous settings on both devices?
I always take a screenshot of the router configuration before making any major changes.
It’s difficult to say anything helpful from a distance as we can’t know what you changed and how the settings for both devices now work together.
Did you backup your Asus router so that you can at least restore the Asus to previous settings?
If you have changed something in the DHCP settings on one or both routers, this may be the cause.
Solution
Google your ISP and see if they use CGNAT. If they do - ROON ARC wont work.
I live in Australia - most ISP use CGNAT - but if you call them - they can take you OFF it. Or you can pay small amount to have non CGNAT IPV4.
I had all the same issues above and tried all solutions with Asus Router. ONLY removal of CGNAT fixed it.
It should say “failed” with a message that the port is closed - this actually means the port is available to the internet but the test wasn’t able to handshake/talk to roon.
If the test passes and says “stealth” your port forwarding isn’t working
NOTE you want this test to fail as it is testing your firewall is closed – a fail indicates that your port forward is working
Interestingly, I don’t have Port Forwarding enabled on my DSL-AC68U and ARC connected automatically like a charm. However, I did check that NAT and UPnP were enabled before upgrading.
I don’t think these issues are ASUS router specific. I had the same error message as mentioned above at first. Tried all the suggested changes which didn’t help. In my case the problem was the firewall of my NAS. I’m running my Core on my Synology and had to change the port forwarding in the Synology firewall as well as in my Asus router. Now it works fine. So it looks like these issues are related to multiple firewalls in your network or double NAT.
That might solve the problem as you won’t have double NAT anymore.
You would then have to make all the settings manually in the BT HUB. Can the Hub use UPnP?
I would try that first.
If that doesn’t work, disable UPnP again and enable port forwarding if the hub allows for it.
Then manually set up everything for port forwarding there.
Wish you that it works.
However, if not and you want to use ARC, you should consider purchasing another router that can be set to bridge mode.