Another one... Port Forwarding: Comcast / Airport Router

ARC is unable to connect to Roon Server:

Running on:
Mac Mini
macOS 11 Big Sur
Comcast Gateway - in Bridge Mode

  1. Comcast Xfinity
  2. Xfinity XB8 gateway cable modem / router in bridge mode (modem only)
  3. Apple Airport Extreme Router is connected to the Comcast modem
  4. No VPNs, proxy servers, or enterprise-grade security


“connectivity”: {“status”:“NetworkError”,“status_code”:502,“error”:“error: Error: connect EHOSTUNREACH, response code: undefined, body: undefined”},
“external_ip”: {“actual_external_ip”:“”,“router_external_ip”:null},
“natpmp_autoconfig”: {“server_ip”:“”,“found_natpmp”:true},
“upnp_autoconfig”: {“status”:“NotFound”}

ARC cannot connect to Roon server.

I’ve reserved an IP for the machine running Roon Server in DHCP settings of my Airport Router:

Screen Shot 2022-09-24 at 2.50.01 PM

And forwarded port 55000 to this IP address:
Screen Shot 2022-09-24 at 2.50.21 PM

NAT port mapping protocol is enabled:
Screen Shot 2022-09-24 at 2.52.28 PM

I’ve noticed that my public IP doesn’t seem to be the same as that reported by my modem. I think I Comcast provides dynamic IPs. Is this the problem?

Thanks for any help you can offer.

Hi Jim,

Is port number 55000 the port number which is displayed in the Roon app under Settings → Roon Arc? If not, you should change the port forwarding to the port number which is mentioned in the Roon Arc setting tab in the Roon app.

Hope it helps.

Kind regards,


1 Like

Thanks for the response.

It is not. I must have misunderstood the directions. I thought 55000 was universal for Roon ARC. Will report back.

Yes. That worked. I feel pretty dumb because I thought it was weird that the listening port didn’t match the forwarded port. I told myself it was some NAT on the LAN side.

How did I convince myself it was 55000?

1 Like

I think i now why…

This is from the manual. In my opinion this should be changed to something like Check the port number from Settings → Roon ARC in the Roon App.
@support is that an idea?

@Jim_Meyer great it’s working now!

Kind regards,


Yep. That’s it!

This topic was automatically closed 36 hours after the last reply. New replies are no longer allowed.