ARC connection failure with Roon despite correct settings (ref#C2RNJI)

[Geert_Wanten]

What’s happening?

· I'm having trouble with Roon ARC

What best describes your issue with ARC

· I can't log into ARC but I can log into Roon

How can we help?

· None of the above

Other options

· Other

Describe the issue

Despite Roon saying that connection with ARC is fine I cannot connect with ARC without wifi.
I run ROCK on a NUC directly attached through ethernet cable to my router; port forwarding TCP protocol with IP address fixed: 192.168.2.109 and port forwarding at 55002: ARC says that Roon server cannot be found

Describe your network setup

KPN Experia Box V10; Intel NUC

[Keith_Hunten]

I also have lost ARC connectivity. A solution that does not require redownloading my library would be greatly appreciated!

I’ll also add that ARC stability continues to be quite vexing to put it politely.

[connor]

Hi @Geert_Wanten,

If you’ve set up port forwarding on a router/modem combination provided by KPN, there are two reasons why it might suddenly fail:

1. KPN has implemented Carrier-Grade Network Address Translation above the level of your account, blocking port forwarding. In this case, you’ll need to use the Tailscale network interface in ROCK to bypass CG-NAT instead of using port forwarding. See here:
   https://help.roonlabs.com/portal/en/kb/articles/tailscale-setup-instructions-roonos-roonserver

2. The second possibility is that RoonServer cannot traverse a local NAT layer imposed by a router in order to reach ARC through the open port. You can usually resolve this by changing any port forwarding rules you’ve created to use a different port range, eg. 56000. However, we would need to see an error message presented in Roon Settings → ARC to ascertain the specific blockage.

In general, we recommend Tailscale for ROCK uses with newer NUC models, since it’s more reliable for NAT traversal than port forwarding. Tailscale is not subject to your ISP’s implementation changes, and it’s impervious it changes in your local router setup provided the ROCK still have an internet connection.

@Keith_Hunten, welcome to the Community. Diagnostics from your ARC account don’t indicate you have an issue with port forwarding, but rather that the session layer has become unauthorized, requiring reinstall. There is ongoing work to prevent these token authorization issues from occurring - the most common culprits are a) restoring a Backup of RoonServer or b) going 1-2 weeks without opening ARC in the phone. Downloading the app again is the only workaround for now, but this condition should be prevented with future ARC releases.

In any case, a reinstall is the only workaround for now. This is a separate issue from the OP’s problem above, so we’ll need to split this into a separate dedicated thread for troubleshooting.