BT Smart Hub 2 Gateway I.P. Locked

[Les-Gibson]

@Crimliar 

The gateway is the hub not the line and you don't want two devices on the same network with the same IP address, this is called an IP clash.

Remember the old analogy of an IP address, it's a bit like telling the postman which house you live in so that he can deliver your packages to the correct address, now think of the confusion it would cause if there were two houses in your street with the same address, where should your postman (the internet) deliver you packages (packets) then?

Believe me, you do not want IP duplication on your network

[SamuraiMelon]

They both have exclusive addresses.

The 3rd party is the main router with the DHCP server and I've even reserved the I.P. address on the 3rd party router based on the MAC address of the hub.

However, because the BT hub refuses to change its address from 192.168.1.254, my 3rd party router has never seen that mac address connect to it.

Not that it should matter, but its important to add I've got a switch in the middle, with a reserved i.p. from the 3rd party router.

So it essentially goes WAN -> 3rd Party Router (DHCP Server) -> Switch (Reserved I.P. #1) -> BT Hub (Should be Reserved I.P. Address #2)

[Crimliar]

I'll have a go at duplicating your setup tonight I can manage:

ONT - GT-AX6000-Tpl1008-SH2

But as I've already set my SH2 to 192.168.50.254 with it's DHCP off (and the GT-AX6000 set as the gateway - ie the device that interfaces between the LAN and WAN) I don't think I'm going to have the issue.  I only did this so I could play with the settings and see what the SH2 is capable of (not much), but it all worked.

*When you made your changes isn't the "SAVE" button in a strange place - very odd!

**I might also have a go at looking at how the save is triggered, and even use the "Lynx" browser to see if that helps spot anything.

[Les-Gibson]

You could try and get round it by changing the subnet mask on the SH2 to 255.255.254.0, this would give you host addresses in the range of 192.168.0.1 to 192.168.1.254 thus covering both subnets

EDIT!!! Correction, on the third party router, which won't see 192.168.1.254 with the standard subnet mask and therefore the problem would remain

[Crimliar]

Okay, so I've replicated-ish what our OP is trying to do.

First step was to factory reset the SH2 with it unplugged from everything apart from the mains:

Next step and this is where it was a little quirky.  Set the SH2 to 192.168.50.254 so that it'll fit in with my existing router.  I had to do this in two parts, changing the IP address, save, reconnect and then turn off the DHCP and save:

When I tried doing everything in one step, even setting the IP address on my WiFi adapter it wouldn't work if I didn't split this into two steps.

After this I connected the SH2 to my TL-SG108E V3 (the correct model number this time).  At this point, I removed the set IPv4 from my WiFi adapter properties and could connect to the internet using the SH2 as an Access point.  Looking at the device table on the GT-AX6000 the SH2 could be seen there at 192.168.50.254 (remember that discovery is performed using the MAC address - the IP address comes later).  Oh, the GATEWAY address whether I connect to the SH2 or the GT-AX6000 is 192.168.50.1 AS IT SHOULD BE.

So, I cannot replicate the issue.  I also tend to think it's not an issue with the router, it's not the kind of fault you'll see from bad code or failing hardware.  This leads me to think it has to be something to do with the browser settings or the environment on the machine you are using.

*images compacted as much as is sensible...

[simon3270]

If you change the gateway IP to a different subnet, you must initially leave DHCP enabled and set a custom DHCP range to be in that same subnet, and save your settings. Then turn off DHCP and save settings again.

The code on the smart hub clearly checks for a valid DHCP range, even if DHCP is turned off.