Roon ARC : Can I use Forward Port form DDNS?

My ISP use CG-NAT. I contact them about method to forward port. They give DDNS service for port forwarding instead unlock the NAT.

Add forward port router.
image

I test a connection with roon display. It’s work.

But the path of ARC not through the DDNS. In the Roon ARC app have no any setting, what should I do?

DNS has nothing to do with ARC and is not needed.

DNS is a database for mapping things. It’s most often used mapping is Fully Qualified Domain Name (FQDN) to an IP Address. Or, in other words, www.server.com to 192.168.7.100. The Internet works off of these addresses. Our brains work off names. It’s a convenience but has nothing to do with connectivity.

Dynamic DNS is a service that “discovers” changes in IP Addresses to keep the FQDN pointed at the right address. This is commonly used on residential internet connections where your public IP address might change but your camera app wants a consistent way to get to ipeverywhere.cameraapp.com

ARC, in a very simplified (and maybe inaccurate) explanation works as a private dynamic DNS. The ARC service tracks changes to the public IP of your Core but only exposes that IP to the ARC client once you login. The “discovery” of your Core IP changing is handled by ARC. You don’t need DDNS.

But, none of this… not any of it… has anything to do with ARC connecting to your Core at an address and port. That part all needs to work. And it won’t work via dynamic CGNAT.

Now, I’m a bit intrigued why your ISP said to use DDNS. If they actually put the proper infrastructure in place to let you build forwarding rules within the CGNAT it’d be excellent and a first. But there isn’t enough info here for me to determine that.

So… Who is your ISP?
Where are you building those forwarding rules? Is that on your router? Or within some ISP provided portal?

The reason “display” works is probably because you’re on your local network. It’s still just connecting to your Core via the local network. That’s expected to work. What is probably not working, and what’s needed for ARC, is connecting from another network.

This picture is Port Forwarding on ISP website
www.totddns.com

I use mobile service to access a display. Can access from outsite.

My ISP’s DDNS service is different from other DDNS service. They said the system will bypass NAT if you use forward port number from website to forward port at you router. CCTV can also be used this way.

Check DDNS forward port.

ISP website

Would you like more information? I don’t know what to do.

Hi @Surasiri_Ruamsap,

Please accept my apologies for the delayed response as we work diligently to reach every ARC-related issue.

It would help us if you’d provide a few details missing from the tech support team’s understanding of your setup:

I’m afraid @ipeverywhere is correct that if your service provider has carrier-grade network address translation, you’d almost certainly have to bypass it entirely to allow ARC to work at all while on a mobile connection.

So, can you take us back to the beginning? It appears you have a MultiplenNAT error in your initial diagnostics from earlier this month. This can either be your ISP’s CG-NAT, or a redundant layer of NAT in your local network.

Let’s first double-check for the latter.

  1. How many routers are in your setup?
  2. Is it just one modem/router combination, or do you have a second router downstream?
  3. Are you using a VPN?
  4. Please pass these questions to your ISP’s support team, if possible and at your convenience:
  • Have you implemented carrier-grade NAT for my account level?
  • Have you fully implemented IPv6, or do you have IPv4 addresses available?
  • Can I request a routable public IPv4 address to support port forwarding?
  • Are there any ports you have reserved at the ISP level I should be aware of?
  1. How many routers are in your setup?
    Ans : One router is zte f670.

  2. Is it just one modem/router combination, or do you have a second router downstream?
    Ans : zte f670 is modem/router combination. I have no second router downstream.

  3. Are you using a VPN?
    Ans : No.

I’ve asked your questions before.

  • Have you implemented carrier-grade NAT for my account level?
    Ans : Yes. my account is carrier-grade NAT.

  • Have you fully implemented IPv6, or do you have IPv4 addresses available?
    Ans : IPv6 is unable for my packet. I will pass the question to ISP’s support team again.

  • Can I request a routable public IPv4 address to support port forwarding?
    Ans : No. They offer DDNS services instead for port forwarding.

  • Are there any ports you have reserved at the ISP level I should be aware of?
    Ans : The DDNS service allows 10 fixed ports for port forwarding.

I have a question, Is it possible to have the Roon ARC application can input the host name for connection?

Hi @Surasiri_Ruamsap,

Thank you for your detailed response.

If you’ve configured a matching port assignment in Roon and the router’s web administration (one of the reserved ports for forwarding per your ISP’s instructions, for example) and still receive a 504 ETIMEDOUT diagnostic message, then it’s likely this CG-NAT is simply innavigable.

It sounds like your ISP won’t offer your account a routable IPv4 address, likely due to an IPv4 shortage in your region.

In that case, until the team implements different methods for connecting outside the home (we’re working on it), you’ll have to pursue a VPN or other unofficial workaround in our #tinkering section or await your ISP’s response. Please see our tracking thread for CG-NAT issues here for updates: ISPs and Routers: List of Known Solutions and Workarounds