Eero routers and port fowarding

R-tulip · 19 Aug 2025 at 21:27

Hello all

Im trying to set up a dedicated server for friends to use for Project Zomboid.

Ive followed all the guides I can and it seems to boot up correctly, however no one but myself can connect and I imagine that is because its local to my PC.

As stated I have an Eero router. ISP is Brillband.

As far as I can tell I can access my router settings through my browser and have to do everything through the app.

I need the following ports to be open,

16261 UDP
16262 UDP - Direct Connection Port

and

8766, 8767 UDP - for earlier builds of the game

As far as I can tell with the app I have done so.

I've made specific rules in my firewall for those ports and created a rule for the server itself but still no joy.
Looking at <netstat -ano> in command prompt the ports don't seem to be listed. Not sure if that's what I should use to check but its the only thing I know.

I've tried with the firewall off. I've tried with my VPN on and off using the IP the VPN gives me and my normal IP.

According to IP config my local IP ends in 102 where as in the Eero app it ends in 103. Not sure if that makes any difference but I've created a new rule for both to which I get told there are conflicts of port rules already established if I try to add them to the second IP reservation.

With my port forwarding on for ports 16261-16262 in the app I get this in the server cmd:

LOG : Network , 1755634519243> 15,796,219> [19-08-25 21:15:19.243] > ZNet: Using http://192.168.4.1:1900/ipc to map external UDP port 16261 to local port 16261...
LOG : Network , 1755634519244> 15,796,220> [19-08-25 21:15:19.244] > ZNet: Checking if the port is already mapped...
LOG : Network , 1755634519267> 15,796,242> [19-08-25 21:15:19.267] > ZNet: Failed to get existing mapping: 714 (NoSuchEntryInArray)
LOG : Network , 1755634519267> 15,796,243> [19-08-25 21:15:19.267] > ZNet: Adding mapping to the routing table...
LOG : Network , 1755634519326> 15,796,301> [19-08-25 21:15:19.326] > ZNet: UPNP_AddPortMapping() has failed with code 718 (ConflictInMappingEntry)
LOG : Network , 1755634519326> 15,796,302> Failed to add port mapping, retrying with zero lease time
LOG : Network , 1755634519327> 15,796,302> [19-08-25 21:15:19.327] > ZNet: Using http://192.168.4.1:1900/ipc to map external UDP port 16261 to local port 16261...
LOG : Network , 1755634519328> 15,796,303> [19-08-25 21:15:19.327] > ZNet: Checking if the port is already mapped...
LOG : Network , 1755634519337> 15,796,313> [19-08-25 21:15:19.337] > ZNet: Failed to get existing mapping: 714 (NoSuchEntryInArray)
LOG : Network , 1755634519338> 15,796,314> [19-08-25 21:15:19.338] > ZNet: Adding mapping to the routing table...
LOG : Network , 1755634519382> 15,796,357> [19-08-25 21:15:19.382] > ZNet: UPNP_AddPortMapping() has failed with code 718 (ConflictInMappingEntry)
LOG : Network , 1755634519382> 15,796,358> Failed to map default port
LOG : Network , 1755634519383> 15,796,359> [19-08-25 21:15:19.383] > ZNet: Using http://192.168.4.1:1900/ipc to map external UDP port 16262 to local port 16262...
LOG : Network , 1755634519383> 15,796,359> [19-08-25 21:15:19.383] > ZNet: Checking if the port is already mapped...
LOG : Network , 1755634519395> 15,796,371> [19-08-25 21:15:19.395] > ZNet: Failed to get existing mapping: 714 (NoSuchEntryInArray)
LOG : Network , 1755634519395> 15,796,371> [19-08-25 21:15:19.395] > ZNet: Adding mapping to the routing table...
LOG : Network , 1755634519438> 15,796,414> [19-08-25 21:15:19.438] > ZNet: UPNP_AddPortMapping() has failed with code 718 (ConflictInMappingEntry)
LOG : Network , 1755634519438> 15,796,415> Failed to add port mapping, retrying with zero lease time
LOG : Network , 1755634519440> 15,796,415> [19-08-25 21:15:19.440] > ZNet: Using http://192.168.4.1:1900/ipc to map external UDP port 16262 to local port 16262...
LOG : Network , 1755634519440> 15,796,415> [19-08-25 21:15:19.440] > ZNet: Checking if the port is already mapped...
LOG : Network , 1755634519453> 15,796,429> [19-08-25 21:15:19.453] > ZNet: Failed to get existing mapping: 714 (NoSuchEntryInArray)
LOG : Network , 1755634519453> 15,796,429> [19-08-25 21:15:19.453] > ZNet: Adding mapping to the routing table...
LOG : Network , 1755634519490> 15,796,465> [19-08-25 21:15:19.488] > ZNet: UPNP_AddPortMapping() has failed with code 718 (ConflictInMappingEntry)
LOG : Network , 1755634519490> 15,796,465> Failed to map AdditionUDPPort

If i remove the port forwarding rule for 16261-16262 on the app I get this in the server cmd:

LOG : Network , 1755634783964> 16,060,940> [19-08-25 21:19:43.964] > ZNet: Using http://192.168.4.1:1900/ipc to map external UDP port 16261 to local port 16261...
LOG : Network , 1755634783965> 16,060,941> [19-08-25 21:19:43.965] > ZNet: Checking if the port is already mapped...
LOG : Network , 1755634783976> 16,060,952> [19-08-25 21:19:43.976] > ZNet: Failed to get existing mapping: 714 (NoSuchEntryInArray)
LOG : Network , 1755634783977> 16,060,952> [19-08-25 21:19:43.976] > ZNet: Adding mapping to the routing table...
LOG : Network , 1755634784374> 16,061,349> [19-08-25 21:19:44.374] > ZNet: UPNP_AddPortMapping() succeeded, testing now...
LOG : Network , 1755634784393> 16,061,368> [19-08-25 21:19:44.393] > ZNet: UPNP_GetSpecificPortMappingEntry() succeeded, seems that we're good
LOG : Network , 1755634784393> 16,061,369> Default port has been mapped successfully
LOG : Network , 1755634784394> 16,061,370> [19-08-25 21:19:44.394] > ZNet: Using http://192.168.4.1:1900/ipc to map external UDP port 16262 to local port 16262...
LOG : Network , 1755634784394> 16,061,370> [19-08-25 21:19:44.394] > ZNet: Checking if the port is already mapped...
LOG : Network , 1755634784407> 16,061,383> [19-08-25 21:19:44.407] > ZNet: Failed to get existing mapping: 714 (NoSuchEntryInArray)
LOG : Network , 1755634784407> 16,061,383> [19-08-25 21:19:44.407] > ZNet: Adding mapping to the routing table...
LOG : Network , 1755634784802> 16,061,777> [19-08-25 21:19:44.802] > ZNet: UPNP_AddPortMapping() succeeded, testing now...
LOG : Network , 1755634784824> 16,061,799> [19-08-25 21:19:44.824] > ZNet: UPNP_GetSpecificPortMappingEntry() succeeded, seems that we're good
LOG : Network , 1755634784824> 16,061,800> AdditionUDPPort has been mapped successfully

Any knowledge on the subject would be greatly appreciated.

Anything you need to know that will help give me a shout.

Cheers

becks · 19 Aug 2025 at 21:42

Had the same headache with Eero before – the app is so locked down it fights with the game’s own UPnP. From your logs it looks like double rules are clashing: if you forward in the app and the server tries UPnP, you get that 718 conflict. What fixed it for me was killing the manual forwards and letting UPnP handle it alone, plus making sure the IP reservation matches your PC exactly. Awkward, but once set, it stuck.

R-tulip · 19 Aug 2025 at 21:55

OK thanks becks.
I'll have another mess about tomorrow. I've had enough of fighting it today haha.

In terms of removing the manual forwards, is it worth removing all the rules I've added to my firewall and VPN?

Disco_P · 19 Aug 2025 at 21:57

Brillband uses CG-NAT so that'll be a hurdle you might have trouble with.

R-tulip · 19 Aug 2025 at 22:09

That does look like an issue.
I can get a dedicated IP through my VPN, at a cost obviously, but may be worth paying just so I don't have to deal with this anymore :cry:

Thanks for the info Disco

ChrisD. · 20 Aug 2025 at 06:49

You could run up cloudflared as a container, create a free Cloudflare account then set up free tunnels. Also more secure than port forwarding. Not sure it would be performant enough as I don’t know the app/game.