router behind another router

[unclebob1]

I've picked up a THG3000 router, which I want to use BEHIND my existing router.

Router A for example has 192.168.1.1 as its internal ip, with a dhcp range 2-10 

It is connected to the internet directly.

I want to connect Router B such that it picks up a WAN ip from the dhcp pool from Router A, and then has its own internal LAN IP of say 192.168.2.1 with its own DHCP range of 192.168.2.2-10

Is this possible with the THG3000 running as router B? I tried to connect a cable between LAN port on Router A to WAN port on router B, but the THG3000 interface couldn't figure out that it had a connection to the internet - but the port was showing as active - so it knew there was a connection.

The aim for this setup in case anyone will ask why is that I want to separate the kids devices directly to router A and then have a second network for my devices. Happy for my devices to connect to devices on kids network, but dont want kids devices connecting to my devices.

I understand the double Nat problem etc, but this doesn't concern me as I don't do any port forwarding in my use.

[Cynric]

If you have this setup

BT Green Cabinet -> THG3000 (192.168.1.1) -> Netgear Router (192.168.0.1) -> LAN

Then ...

THG3000 connects to VF and provides a WAN to the second router

Second router does not know about VF and it doesn't care about VF. Second router provides DHCP, WiFi, LAN, and is where the DNS settings are configured. The WAN port of second router is connected to LAN port of THG3000. (EDITED)

[Jayach]

---

@Cynric wrote:

If you have this setup

BT Green Cabinet -> THG3000 (192.168.1.1) -> Netgear Router (192.168.0.1) -> LAN

Then ...

THG3000 connects to VF and provides a WAN to the second router

Second router does not know about VF and it doesn't care about VF. Second router provides DHCP, WiFi, LAN, and is where the DNS settings are configured. The internet port of second router is connected to WAN port of THG3000.

---

I don't think that will work, surely it should be a LAN port of the THG3000

[Cynric]

.@Jayach Haha good spot. Thank you. I have edited.

[unclebob1]

Hold up, so the wan port on thg3000 is an OUT from the thg 3000 to provide a connection to a second router?

[Jayach]

No, that was a mistake, @Cynric has corrected it.

[Jayach]

---

@unclebob1 wrote:

So if I go with voda, I'd have two, the second would still be in the same position or will it recognise that the outer one is voda and allow connectivity via wan?

---

I have a spare THG3000 router, and have tried to get it to work behind my main THG3000, but no way can I get it to connect to the internet. I think the firmware just won't allow it.

[Anonymous]

There are a few possibilities as to why this would be but without the kind of wireshark packet inspection that VF would seem to prefer we not do, it's hard to say for sure.  On top of just the issues from network translating local addresses and VLANs, there is also the possibility that the secondary router is trying to create a PPPoE connection through the primary connection, using either a token or a password/username allocated to another user/line.

It's one of the reasons that third party routers even do a better job of Double NAT - there isn't all that additional garbage to deal with!  FYI, Asus routers fair worse than most third-party routers when embedded in a double NAT due to the way they handle the WAN port.

*I'm definitely out of my comfort zone on this - feel free to challenge/correct me!

[Cynric]

I had just connected my THG3000 to the LAN, now don't laugh but I like a challenge and the setup looks like this (no sniggering at the back):

OpenReach -> ZyXel Router -> Netgear Router (192.168.0.1) -> THG3000 (10.0.0.1) -> Laptop

Because the THG cannot get PPP (I am not a VF customer any more - you can tell by the huge smile) it will not even pass local traffic to 192.168.0.1, there is something "baked in" with the firmware that wants a direct connection to the VF mothership.

[unclebob1]

Thanks for testing, so it seems that the router is only good enough to extend the WiFi range, with the main router still doing DHCP etc and connected Lan to Lan. I guess the next question (which I believe the answer to is no!) Is there any alternative firmware or is the Vodafone firmware the only option? (Openwrt is not supported)

[Jayach]

@Cynric wrote:

Because the THG cannot get PPP (I am not a VF customer any more - you can tell by the huge smile) it will not even pass local traffic to 192.168.0.1, there is something "baked in" with the firmware that wants a direct connection to the VF mothership.

---

In my tests both THG3000's can authenticate to Vodafone if used separately, but can't when connected via the others LAN.

---

@unclebob1 wrote:

Thanks for testing, so it seems that the router is only good enough to extend the WiFi range, with the main router still doing DHCP etc and connected Lan to Lan. I guess the next question (which I believe the answer to is no!) Is there any alternative firmware or is the Vodafone firmware the only option? (Openwrt is not supported)

---

You are correct, the answer is no, there is no alternative firmware. (as far as I know)