Wifi hub loses admin interface and DHCP server after a period

[mr-b]

I've just switched from BT to Vodafone and I had to change my Vodafone Wifi Hub LAN interface straight away to 192.168.0.1 as it's behind my firewall (which is on 192.168.1.1). This was no problem but I noticed after a short while that the admin interface was unresponsive. Ping to 192.168.0.01 was fine though.

The laptop that I'd plugged into the back of the router also could not get an ip address after I'd disabled/reenabled its LAN interface. I restarted the router and everything worked again. But after a short period the same thing happened.

I logged it with support but they weren't aware of this being an issue and insisted that I change it back again to 192.168.1.1, even though I explained why I could not easily with all my existing kit (firewall, wifi APs etc. etc.). However I can reproduce it easily, so what happens next?

The router is a THG3000, firmware 19.2.0203-3261005.

What's the next step?

[Anonymous]

You might want to tell us what make & model the firewall is, how you've connected the VF modem/router to it, and what additional settings you've made while trying to get it to work.  *I assume you are on Gigafast, as otherwise, you'd need a modem too, and I'm curious as to how you're handing the needed VLAN ID too!

I think it would be fair to say that the VF equipment does not play nicely when connected to other modems, routers, and hardware firewalls!

[mr-b]

The firewall is a red herring. The problem also exists with a laptop plugged into the back of the router.

I don't know Gigafast - mine is just plain old "Superfast" FTTC via VDSL. The THG3000 has a integrated modem.

This morning the admin interface returned (and through the FW, but that's irrelevant)! I grabbed the syslog but all it contains is bunch of DHCPv6 msgs and nothing else over a short period of time though I note theuptime is only 5h and I did't reboot it during the night! I'll ask on another thread about if it's possible to filter it ...

But the admin page has hung now again.  😞 Laptop also fails to get a DHCP address.

SSH access is refused, anyone found a way in?

Also from the other postings on here I doubt support are going to be of much help, they'll just insist I go back to 192.168.1.1. 😞

It's a shame as I had Vodafone a couple of years ago and it was fine, but obviously the 'new improved' router isn't so great.

[clint_flick]

Hi

Many years ago I had to change (hack) the registry and change to 0.0.0.0 for an IP address, which worked.

C:\>route /?

Manipulates network routing tables.

CIDR is the name of the game.  

ip route 0.0.0.0 0.0.0.0 192.168.10.1

But not a lot of use for TV I expect.

[Anonymous]

My attempt at being diplomatic here failed.  I was trying to find out what additional equipment you are using and how you have it connected so I could rule out what the symptoms suggest!

It sounds as though you have two competing DHCP servers, each issuing local IPs within their own subnet, but existing on the same network segment.

Fin

[mr-b]

Ha, Ok just for you.

Internet

|

VDSL

Voda router

LAN changed to 192.168.0.1 static with DHCP scope of 192.168.0.x - y for that subnet. (Class C). Wifi disabled.

|

WAN 192.168.0.x - DHCP client enabled

PF Sense box

LAN 192.168.1.1 static - DHCP server enabled for that subnet

If I pull the Pfsense WAN connection to the Voda router (LAN port) and leave the laptop in the back of the Voda router LAN port the exact same admin symptoms occur, even if I do a DHCP renew or a LAN port disable/enable on the laptop.

Sometimes ping from laptop to 192.168.0.1 works, sometimes it doesn't. Sometimes the laptop gets an ip via  Voda DHCP, sometimes it doesn't.

If I restart the Voda router, admin access and DHCP server all works, for a while.

The same setup all worked fine with Virgin and BT routers (and Voda before). It's just this Voda router which seems to have issues.

[network123]

---

@mr-b wrote:

Ha, Ok just for you.

Internet

|

VDSL

Voda router

LAN changed to 192.168.0.1 static with DHCP scope of 192.168.0.x - y for that subnet. (Class C). Wifi disabled.

|

WAN 192.168.0.x - DHCP client enabled

PF Sense box

LAN 192.168.1.1 static - DHCP server enabled for that subnet

If I pull the Pfsense WAN connection to the Voda router (LAN port) and leave the laptop in the back of the Voda router LAN port the exact same admin symptoms occur, even if I do a DHCP renew or a LAN port disable/enable on the laptop.

Sometimes ping from laptop to 192.168.0.1 works, sometimes it doesn't. Sometimes the laptop gets an ip via  Voda DHCP, sometimes it doesn't.

If I restart the Voda router, admin access and DHCP server all works, for a while.

The same setup all worked fine with Virgin and BT routers (and Voda before). It's just this Voda router which seems to have issues.

---

Try changing the VF router to something completely different, try 192.168.100.1 and DHCP 192.168.100.x.

Are you using subnet mask 255.255.255.0 for all of your subnets?

[Anonymous]

In order to prove that it is indeed an interaction between the VF router and the Pfsense device, I think you'll need to unplug the Pfsense box, reboot the VF router and then see what happens when you connect your laptop (having previously released its leases) to the back of the router.

My personal experience with Pfsense is very minimal, and most of it has been bad!

It does though seem as though the Pfsense box could be expressing what should be its subnet over the WAN port in addition to the LAN ports (as if it had been set up as a switch rather than a router) and hence you would get two DHCP servers on the network offering up IPs on different subnets, whichever gets there first being the winner (even a device plugged directly into one device can end up being served an IP from the other)!  At the moment based on the description of the problem, this still seems more likely to me than the classic "double NAT".

Q: Have you considered just getting your username and password and replacing the VF modem/router with a VDSL modem?

[mr-b]

Finally got some time to do some experiments.

 I unplugged pfSense from the router and restarted the direct router-attached laptop, it received a correct DHCP address but the GUI was still non-reponsive. A Wireshark capture of the GUI session showed TCP keepalives but no reponse to the HTTP GET.

Then I restarted the router and changed the ip to 192.168.100.1 and DHCP server scope - all with Class C addresses - and it works fine of course. I also changed the DHCP lease from infinite to 24h, just in case.

But then the GUI fails to respond after an hour or so, just as before.

Pfsense has been fine in the exact same deployments before - the only diff is this new Voda router. Also Pfsense's DHCP server is on a different scope entirely so it wasn't that.

And yes by this time my 80/20 "flogging a dead horse" rule kicked in so I ordered a Huawei Echolife fibre modem! The irony was that I'm sure I used to have one ages ago but it got recycled in a clearout. Hopefully it won't be too painful obtaining the auth details.

The other thing that tipped it was that the GUI's Expert mode had so few parameters so I guess it's meant for basic deployments only and so support just won't be interested in anything "different" despite the UI allowing you to change the LAN IP.