Strict NAT and Asuswrt-Merlin LTS

[frazor77]

Hi, since moving to the LTS fork of Asuswrt-Merlin (Which has been fantastically stable I might add) I've started to see Strict NAT warnings in some older games (e.g. Atomega). I've had a good ol' search and I can't seem to find a solution/setting to remedy this. Does anyone have any pointers? I'm also not sure if its due to some difference on the TLS fork or just a coincidence, but moving to that version and defaulting all my router settings is round about when I started seeing it. Advice welcome.

 

[ColinTaylor]

Apart from the warning message do you have an actual problem?

Is the WAN IP address shown at Network Map > Internet status > WAN IP the same as that shown by https://canyouseeme.org/

 

[frazor77]

I do indeed, the games that give the Strict NAT warning do not connect to online sessions - one possible caveat Atomega (which is the game I'm using to try and fix this, partly because my Son wants to play it but also because it launches quickly and shows the warning on the main menu screen) is neither particularly new nor has a particularly active player base... so it could be there aren't enough people online playing it anymore? (although for now I'm running on the assumption that's not the issue here given the warning for Strict NAT in that game specifying online sessions may not work at all)

The WAN IP is the same as shown on my router network map as it is on canyouseeme.org

 

[ColinTaylor]

Strange. I would expect you to have "moderate" NAT.

Make sure you have UPnP enabled on WAN > Internet Connection. If it's already enabled try changing the UPnP STUN setting and see if that makes a difference.

What were you using before the LTS fork?

What router model do you have and what version of LTS are you using?

 

[Vexira]

I do indeed, the games that give the Strict NAT warning do not connect to online sessions - one possible caveat Atomega (which is the game I'm using to try and fix this, partly because my Son wants to play it but also because it launches quickly and shows the warning on the main menu screen) is neither particularly new nor has a particularly active player base... so it could be there aren't enough people online playing it anymore? (although for now I'm running on the assumption that's not the issue here given the warning for Strict NAT in that game specifying online sessions may not work at all)

The WAN IP is the same as shown on my router network map as it is on canyouseeme.org

Sounds like an experience I had with symetric Nat, and Grand theft Auto V on the AC 88U I used to have, the issue is resolved with the full cone option in my AX88U.

Well it wasn't the only game that had the issue but like I said it's an issue with symetric Nat.

 

[frazor77]

@ColinTaylor

Router model? ‍ Yeah that's an obvious bit of info I could have shared at the start! its the RT-AC66U. Running LTS 46E8 (24/12/2020). Before that was using the last Merlin 380.70. Broadly speaking the LTS has proven to be more stable (which is why I changed - stability has been key in these Covid times of home-schooling and working from home) but there a few notable feature regressions, so this may be one of them.

I think I did try the UPNP-STUN setting, but will try again and reboot.

@Vexira

Correct me if I'm wrong but I don't think full cone is an option on these older routers?... although have been eyeing up the AX88U - the AC66U has performed admirably, but given my increasingly connected household have been considering an upgrade (but that's for later)

 

[ColinTaylor]

Yes the symmetric/cone options are not available on our routers. That said, I've not seen your NAT issue with my N66U and AC68U running John's firmware. My son has been playing all sorts of online games for years on his PS3, PS4 and PS5 without any problems.

Can you double-check it with another device/game? Also look at System Log - Port Forwarding when running the games to see if it has created any forwarding rules.

 

[frazor77]

Most games are fine, there's only a few games (like 2 or maybe 3) that I've seen this error in.. and TBH Atomega is the only one I can remember at this time. I'll post if I find another. Its not a well know game I grant you

The System Log shows nothing when I run the game. :/

 

[ColinTaylor]

The System Log shows nothing when I run the game. :/

Maybe there's a bug in the MIPS version of miniupnpd? Try running something else that uses UPnP and seeing if that appears in the log. Or SSH into the router and run ps w | grep miniupnpd and netstat -nlp | grep miniupnpd

 

[frazor77]

The outputs are as follows:

admin@RT-AC66U:/tmp/home/root# ps w | grep miniupnpd
  785 admin      872 S    miniupnpd -f /etc/upnp/config
  816 admin     1476 R    grep miniupnpd
admin@RT-AC66U:/tmp/home/root# netstat -nlp | grep miniupnpd
tcp        0      0 0.0.0.0:54187           0.0.0.0:*               LISTEN      785/miniupnpd
udp        0      0 192.168.1.99:41238      0.0.0.0:*                           785/miniupnpd
udp        0      0 192.168.1.99:5351       0.0.0.0:*                           785/miniupnpd
udp        0      0 0.0.0.0:1900            0.0.0.0:*                           785/miniupnpd

 

[ColinTaylor]

Thanks that all looks correct, assuming your router's IP address is 192.168.1.99.

 

[frazor77]

Yep, it is.

 

[Vexira]

@ColinTaylor

Router model? ‍ Yeah that's an obvious bit of info I could have shared at the start! its the RT-AC66U. Running LTS 46E8 (24/12/2020). Before that was using the last Merlin 380.70. Broadly speaking the LTS has proven to be more stable (which is why I changed - stability has been key in these Covid times of home-schooling and working from home) but there a few notable feature regressions, so this may be one of them.

I think I did try the UPNP-STUN setting, but will try again and reboot.

@Vexira

Correct me if I'm wrong but I don't think full cone is an option on these older routers?... although have been eyeing up the AX88U - the AC66U has performed admirably, but given my increasingly connected household have been considering an upgrade (but that's for later)

It's not available like Colin said you would need a newer unit to get the option to be able to enable it.

 

[frazor77]

@Vexira While that's indeed true, I am endeavouring to fix this with my existing hardware if I can - to get to a moderate/open NAT rather than a strict one... or to figure out if I have other (sensible) options

 

[Vexira]

@Vexira While that's indeed true, I am endeavouring to fix this with my existing hardware if I can - to get to a moderate/open NAT rather than a strict one... or to figure out if I have other (sensible) options

Unfortunately it would require Asus to step in an pain an update for that kind of thing similar to what Netgear did for its units, which is if I remember correctly some sort of black box code, the only other option I could think of is manually Port forwarding.

I understand that everything is extremely expensive at the current moment I nearly passed out seeing how much my router currently costs locally compared to what I paied for it.

 

[ColinTaylor]

@frazor77 Have you tried checking the NAT type with another game or application like I suggested. Your problem doesn't sound like something that can simply be fixed by buying a different router that supports symmetric/cone options. You said you didn't have this problem before so something has changed to cause it.

 

[frazor77]

I 'think' the change was going from Merlin 380 to Merlin-LTS 374... but this issue was discovered some weeks later... And I've still not managed to come across (re-discover) another app/game reporting this even though I know I've seen others report this. I did look for some sort of diagnostics tool to help but not sure if something like that exists.

 

[ColinTaylor]

For UPnP I like this tool: https://www.xldevelopment.net/upnpwiz.php

Although you don't actually need a specific tool because you can do it in Windows:

 

[john9527]

Just a thought.....if it's a really old game, perhaps it's not adhering to today's standards of using external ports >= 1024. Ports below this are blocked by default by upnp. You might try changing that setting on the WAN page.

 

[frazor77]

Its not old, 2017. The support page states the following ports: (https://support.ubisoft.com/en-gb/A...bleshooting-connectivity-issues-in-Atomega-PC)

TCP: 27015 - 27030
UDP: 3074, 4380, 27000 - 27030

Now, maybe I can explicitly forward those ports?... but I have TWO PC's on my network (both mine and my sons, when we previously played this game it was often together) so I'm not sure how that would work?

However neither of the methods/tools @ColinTaylor mentions above show these ports or Atomega... (in fact it only shows Minecraft and confusingly not for the (static) IP of the machine