GL-AX1800 (Flint) No internet as secondary router

sebastiencs · 2022-05-14T12:54:42.317Z

Hello.

I just bought the GL-AX1800 and I’m not able to get internet access.
My main router is a DLINK DIR-882, I plugged an ethernet cable on one of its LAN port to the WAN port of the Flint.
The flint has the static IP 192.168.0.156 on the main router.
On the flint, the LAN IP is 192.168.8.1 with the range 192.168.8.200 to 192.168.8.249
I enabled DMZ on the main router for the IP 192.168.0.156.

Here are some pictures showing the configuration on both routers:

DLINK (main router):

image3158×1600 283 KB

image2464×918 95.2 KB

Flint (secondary router):

Capture1057×636 38.5 KB

Capture d’écran 2022-05-14 1445031054×680 87 KB

Capture2895×624 41.5 KB

My main goal is to setup a VPN client (wireguard) on the flint, so that all clients connected to the flint use the VPN.

Thanks for you help !

vvv · 2022-05-14T13:06:50.757Z

Is the D-Link detecting the Flint? Check the client list, and I think D-Link’s also should be able to give the port status of the LAN port you plugged it into.

sebastiencs · 2022-05-14T13:31:52.012Z

Yes, when I click on clients list, the flint does appear, and the port status seems correct.
The flint is connected to the port 3 of the main router:

image968×536 17.4 KB

Not sure if it helps, but when I try to ssh into the flint, it times out, while pinging the flint works.
This is from a computer connected to the main router:

image3838×388 146 KB

And the following is from a computer connected to the flint.
I am able to ssh 192.168.8.1, but pinging google.com and 8.8.8.8 fails:

image921×983 109 KB

vvv · 2022-05-14T13:56:24.124Z

sebastiencs:

I am able to ssh 192.168.8.1, but pinging google.com and 8.8.8.8 fails:

Ha. Weird that google is resolving to 192.168.8.1. Very strange, everything seems to be setup correctly, maybe a factory reset of the Flint could clear something up - just test it with a dynamic IP from the D-Link. That’s all I can really think of, I’m afraid.

xize11 · 2022-05-14T15:19:18.942Z

Hi there!,

It might be that your flint router blocks upstream dhcp responses or concurrent dhcp connections.

Since flint is not the first dhcp inside the network you can try to disable rebind protection under dhcp settings, edit: you can find this in dns settings.

If it seems to happen again there are two other options you can find both via ssh or via luci inside the dhcp settings.

Authoritative, this means this is ment to be the master dhcp if not and you are on a dhcp child or childs, then you can consider unchecking this checkbox, though I have never had problems with it default checked on double routers, its more a flag for more priority over other dhcp imo but might conflict when there are two authoritative dhcp servers.
Domain required, this could also block things unintended when checked which is default.

I think 9/10 times rebind protection should fix the problems.

sebastiencs · 2022-05-14T16:19:28.024Z

@vvv:
maybe a factory reset of the Flint could clear something up - just test it with a dynamic IP from the D-Link

Weird indeed. I tried to reset it, and use dynamic IP, but that still fails.

@xize11
Thanks for the explanation.
I’ve modified the dhcp settings as you recommended, but there is still no internet connection.
Both ping commands (in my screenshot above) fail in the same way.

Here is the dhcp configuration on the flint:

image1280×1426 171 KB

xize11 · 2022-05-14T16:35:51.870Z

Hmm let me think about this,

Could you check if you don’t use static settings on the device you perform the test? (I often make this mistake myself).

Also have you tried to reconnect to flint when renewing lease via ipconfig /release and ipconfig /renew in windows?

From what I see, it should normally work, aslong you put it as router mode and place the cable inside the wan port and you also see a wan ip there from the d-link.

sebastiencs · 2022-05-14T17:44:17.332Z

@xize11

Could you check if you don’t use static settings on the device you perform the test? (I often make this mistake myself).

Yes, the device which is connected to the flint is getting its IP with DHCP, not a static one.
Note that when I run the commands ping google.com and ping 8.8.8.8, it is run from the flint, through ssh.
Though if I run those same command from the device (which is connected to flint), I get the same results.

Also have you tried to reconnect to flint when renewing lease via ipconfig /release and ipconfig /renew in windows?

I just tried that, it didn’t change anything

From what I see, it should normally work, aslong you put it as router mode and place the cable inside the wan port

Yes, the ethernet cable is plugged to the dlink on its LAN port, and the other side of the cable is plugged to the WAN port of the flint.
The flint is setup as router mode.

and you also see a wan ip there from the d-link

Not sure if it’s relevant, but my dlink has actually 2 wan ip: one IPV4 and another IPV6

image3188×2022 438 KB

xize11 · 2022-05-14T20:06:31.307Z

hmm very strange it could be your firmware version which version is it?

from everything I readed, all looks fine configurated, you could try to disable ipv6 and see what it does on wan for flint.

since I also noticed a screenshot you were pinging from d-link subnet and not being able to ssh thats fine, ssh is firewalled from the outside ping not on flint as default openwrt firewall rule, but maybe there is a rebind/dhcp protection on d-link side?

also its not a dns issue I think since also pinging to a ip address failed, have you verified with the wireguard vpn completely off too?

wcs2228 · 2022-05-15T17:12:15.055Z

Can you test disabling DMZ on the DIR-882 and try accessing the Internet (ping, websites) through the Flint and out through the DIR-882? Maybe something is not working with the DIR-882 DMZ.

EDIT:
I noticed that your SSH “ping google.com” thinks the google.com IP address is 192.168.8.1, which is not correct.

I do not work for and I do not have formal association with GL.iNet

sebastiencs · 2022-05-16T08:13:14.959Z

I’ve been able to resolve the issue.

@xize11 hmm very strange it could be your firmware version which version is it?

The firmware was the latest version, 3.213.
While making a factory reset did not work, I’ve downloaded the same version from GL.iNet download center
Once reinstalled, the flint directly worked as router mode, without any configuration needed.
The firmware from factory could have been wrongly flashed/installed ?
There was also some weird errors in logread, which disappeared after I reinstalled the firmware.

I’ve been able to configure the wireguard client and now everything works as expected.

Thank you all for your help !

xize11 · 2022-05-16T08:29:55.047Z

It could be the stock firmware is a older build but still the same version.

From what I know but not 100% sure is that there are two 3.213 versions because I was one of the first ones using it, and that one caused certain issues in where in a very short time it got updated again, the checksum changed and compile time, only the version remained the same but im not entirely sure if this was with 213 or 212, maybe im wrong but somehow this bad version ended up in stock firmware?

Well im happy its fixed now