I have been able to use Arc together with a Nucleus One for months without and problems. I am also using the same provider. The provider modem is in bridge mode so all configuration is done on my router. UPNP is enabled Also have created a forwarding rule just in case that solves the issue but no luck. Help very much appreciated Thank you Kind regards Michael
You ISP is probably providing you with an IP address through CG-NAT - Based on the MultipleNatFound and the router external IP address starting with 100 (Addresses in the 100.64.0.0 to 100.127.255.255 range are reserved for use with CG-NAT).
With CG-NAT in place, port forwarding cannot work and so your only option is to use Tailscale or similar.
You may be able to use wireguard in your Asus router to achieve the same thing.
Some Asus routers have wireguard support built in in the VPN settings section and, with these routers, wireguard can be set up from the web admin pages.
I don’t know whether your AC88U is one such router or not. I had an AX88U and that definitely supported Wireguard. Unfortunately, I don’t have that router any more so I can’t provide specific help.
I do seen to remember that it was not very difficult. Set up wire guard on the router, download the wireguard app on the phone and set up a new wireguard connection on the phone using the information provided by the router.
I your router does not support Wireguard, then Tailscale installed directly on your Roon Server (supported on all Roon servers except the original Nucleus, the Nucleus Plus and some older ROCK installations that use BIOS boot rather than the more modern UEFI boot).
The Roon help centre article on Tailscale can be found at:
Be sure to follow the links for the specific installation instructions for your Roon Server OS.
We’re going to allow this thread to auto-close due to inactivity under the assumption the issue was resolved behind the scenes. Tailscale (see the above post) is the most common solution in cases where ISPs implement CG-NAT.