troubleshooting no WAN IP

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oliver
Posts: 48
Joined: Wed Jun 04, 2014 7:30 pm

troubleshooting no WAN IP

Post by oliver »

Last week we had a huge thunderstorm which seemed to sit directly over my house.

My router (tp-link wdr3600 v1.4; running 1.1.12) looked OK but couldn't get a WAN IP from my ISP. I also couldn't ping the modem LAN IP at 192.168.100.1 from a PC.

I plugged an old router in and all was good. I was back on the internet with a WAN IP and 192.168.100.1 showed good signals.

I tried flashing 1.1.13 (not preserving anything) but it has the same problem.

The only explanation I have is that lightning zapped the WAN port on the router. Is this likely/possible or am I missing something?

I know I can SSH in but is there a way to go into some kind of debug and prove this out?

Lantis
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Joined: Mon Jan 05, 2015 5:33 am
Location: Australia

Re: troubleshooting no WAN IP

Post by Lantis »

What make and model of router?
The only real test is to convert another LAN port to a WAN port and plug it in. If it starts working, device itself is fine and you’ve got a dead port.
This is done through the network config on the command line.
http://lantisproject.com/downloads/gargoyle_ispyisail.php for the latest releases
Please be respectful when posting. I do this in my free time on a volunteer basis.

oliver
Posts: 48
Joined: Wed Jun 04, 2014 7:30 pm

Re: troubleshooting no WAN IP

Post by oliver »

Lantis wrote:
Wed Jul 06, 2022 6:52 pm
What make and model of router?
The only real test is to convert another LAN port to a WAN port and plug it in. If it starts working, device itself is fine and you’ve got a dead port.
This is done through the network config on the command line.
It's a TP-Link WDR3600 (n600) v1.4.

Is the n/w port re-config documented somewhere?

Thanks for the answer, BTW

Lantis
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Posts: 6735
Joined: Mon Jan 05, 2015 5:33 am
Location: Australia

Re: troubleshooting no WAN IP

Post by Lantis »

There's plenty of examples on the openwrt forums for switching a LAN port to WAN.
There's rarely an example that is specific to your device.

If you examine /etc/config/network, you'll see sections like the following:

Code: Select all

config switch
        option name 'eth0'
        option reset '1'
        option enable_vlan '1'

config switch_vlan
        option device 'eth0'
        option vlan '2'
        option ports '0t 1'

config switch_vlan
        option device 'eth0'
        option vlan '1'
        option ports '0t 2 3 4 5'
You can reference it against this table here:
https://openwrt.org/toh/tp-link/tl-wdr3 ... _for_vlans

But basically if "1" is your WAN, and "2" is a LAN port, then just switch them out.
e.g.

Code: Select all

config switch_vlan
        option device 'eth0'
        option vlan '2'
        option ports '0t 2'

config switch_vlan
        option device 'eth0'
        option vlan '1'
        option ports '0t 1 3 4 5'
http://lantisproject.com/downloads/gargoyle_ispyisail.php for the latest releases
Please be respectful when posting. I do this in my free time on a volunteer basis.

oliver
Posts: 48
Joined: Wed Jun 04, 2014 7:30 pm

Re: troubleshooting no WAN IP

Post by oliver »

Thanks so much for the advice. I'll give it a go later on.

oliver
Posts: 48
Joined: Wed Jun 04, 2014 7:30 pm

Re: troubleshooting no WAN IP

Post by oliver »

Thanks again. Swapping the WAN port with a LAN port seems to have done the trick. I'm using my WDR3600 right now.

Code: Select all

$ sdiff -s network.working network.orig 
        option ports '1 2 3 4 0t'                             |         option ports '2 3 4 5 0t'
        option ports '5 0t'                                   |         option ports '1 0t'

Lantis
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Posts: 6735
Joined: Mon Jan 05, 2015 5:33 am
Location: Australia

Re: troubleshooting no WAN IP

Post by Lantis »

Well, at least that works :)
Sucks about your wan port getting fried though :(
http://lantisproject.com/downloads/gargoyle_ispyisail.php for the latest releases
Please be respectful when posting. I do this in my free time on a volunteer basis.

oliver
Posts: 48
Joined: Wed Jun 04, 2014 7:30 pm

Re: troubleshooting no WAN IP

Post by oliver »

Lantis wrote:
Fri Jul 08, 2022 5:35 am
Well, at least that works :)
Sucks about your wan port getting fried though :(
Yeah, I was using all 4 LANs too but I'd rather have gargoyle with 3 LANs than stock f/w with 4. This will tide me over until I find a reasonable deal on a replacement.

oliver
Posts: 48
Joined: Wed Jun 04, 2014 7:30 pm

Re: troubleshooting no WAN IP

Post by oliver »

I wanted to update this because pretty much everything I thought I knew was wrong.

After a short while with LAN4 as WAN, the same problem occurred (WAN IP was lost - the only thing populated in the GUI WAN section was the MAC address.) No matter what sequence or how many times I rebooted the modem and router, it wouldn't pick up a WAN IP.

I tried the latest openwrt (v21) and that worked and therefore disproved the fried WAN theory. I was missing the graphing stuff in gargoyle though so I went back to 1.1.13 and, within the hour, it lost the WAN IP, never to return.

I re-flashed openwrt 21 and all was good until I realised my d/l speed was consistently about 15% of what it should be.

Thought I'd have one last try back on gargoyle 1.1.12 (which had been rock solid since it came out) and it's been working as expected ever since with all 4 LANs in use and the WAN keeping it's IP.

I don't know if this is just coincidence or something else happened with Xfinity but when I flashed 1.1.13 I hit the default for TZ (0 offset) rather than set my real -5 offset. Could this have caused a WAN side issue? The only other thing I noticed was that my WAN IP went from 73.x.x.x to 104.x.x.x and is now back on 73.x.x.x

It's been such a confusing issue for me but 1.1.12 now has 3 days uptime so all is good and I'm happy again.

pythonic
Posts: 230
Joined: Mon Mar 11, 2019 5:47 am
Location: Australia

Re: troubleshooting no WAN IP

Post by pythonic »

oliver wrote:
Sat Jul 30, 2022 8:17 pm
The only other thing I noticed was that my WAN IP went from 73.x.x.x to 104.x.x.x and is now back on 73.x.x.x
Did you notice whether your WAN MAC address changed between the different installations at all?

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