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AngusFlag for United Kingdom of Great Britain and Northern Ireland

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Home Network - IP Conflict

I have just recently changed my network setup and I am having problems.

Current Setup
I have just upgraded to BT Infinity (I am based in the UK).  So, attached to the phone socket I have a BT modem.  Then there is a LAN cable coming out of the modem to a DLAN device (Powerline LAN).

In a cupboard, I have another DLAN device and attached to this I have a BT Home Hub.  This provides a wireless signal.

Also in the house I have DLAN devices attached to TV, Home Computer and Home Server.

The wireless is working fine.  I can connect any device to the WIFI.  However all my DLAN connected devices are not working.  On the home computer it is reporting an error with the IP address.

Previous Setup
It is worth noting what the previous setup was - which worked perfectly.  I had a Netgear Home Modem router.  Therefore the phone line went into the Modem Router and coming out of that was a LAN cable to a DLAN device.


Suggestions?  Should I fix ip addresses for all my DLAN connected devices?  Should I turn off the DHCP on the new BT Router? Should change the IP address range in the BT Router?


Thanks in advance
Avatar of Gajendra Rathod
Gajendra Rathod
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Please check static IP address configuration on your machine.

Exclude that static IP address from DHCP pool address of the router.
Do the DLAN devices have a web management page? If yes, can you access all their pages / do they have individual IP addresses? If all the DLAN devices aren't working, how is your wireless working (I thought you said it was connected to a DLAN device). Most likely, one of the new devices has a default IP thats conflicting with another device. Set them to dhcp or give them static addresses.
Avatar of Angus


Thanks for coming back to me.

I have tried setting a static ip address on my home computer and it did not work.  But I get an error message

"Warning - The default gateway is not on the same network segment (subset) that is defined by the IP address and subnet mask.  Do you want to save this configuration?"

 I have also tried setting the IP range in the hub to 172.x.x.x range so that the 192.168.x range was completely different... also did not work.

When the hub was 172.x.x.x range, I ran ipconfig and it confirmed that static IP address 192.168.x.x was set.

The exact error message that I am getting is "Local Area Connection" doesn't have a valid IP configuration.

As for the question on DLAN - no I cannot log into it.  In the link below is what I am using

Suggestions please?

Many thanks
I didn't mean set a static IP on your computer. All the IP addresses must be on the same subnet.  It doesn't look like the DLAN adapters have IP addresses.

Are all the DLNA adapters linked via the connect button on the bottom?

What are the IP addresses of the BT modem and the BT home hub? Does the modem have a built in router or do you have a separate router?
Avatar of Angus


thanks for getting back to me.

Re the same subnet, when setting the static IP address - I used the same subnet and did not get the error "Warning....." as captured above.

For the LAN adapters. The button at the bottom is for security and it is to pair devices if you are in a building with other tenants.  As I am not... I have not touched the button at the bottom.

The Modem is purely a modem.  It only has one Lan port (the other one is not in use).  The link below is the modem that I have

The IP address for the BT Home Hub & Subnet

I am completely lost....

Avatar of pergr

I suppose the BT Home Hub is doing NAT and/or routing for your networks.

That means that all your appliances should be "on the inside" of the BT Home Hub.

With your set-up you seem to have a mixture where both the inside and the outside of the Hub is connected to the LAN formed by the DLAN devices.

As a test, you can connect the modem to the Hub with a normal Ethernet cable, and see if everything works.
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Pergr - thanks.  I will test this evening - ahead of this - I have a follow up question.

You say that all devices should be on the inside? The reason that I split the modem and the router is to have less IT stuff in my hallway.    Are you saying the setup in having a mixture of in and outside the hub is not possible?

Thanks and will get back to you with results of my text
The Hub is for sure working as a DHCP server on the "inside", and most like the on the BT side of the modem there is another DHCP server that gives an address to the Hub.

The can confuse the PCs, etc, since there are two DHCP servers on the same LAN.

If all devices has static IP addresses, there would not be any problem either, but you can run first run the test above, just to see if this is the problem.
Avatar of Angus



I did the following setup  -

1) ADSL into Modem
2) Modem into BT Hub 3 Wireless Router
3) BT Hub 3 Wireless Router into Powerline LAN (DLAN)
4) TV, Computer, Server connected via their own Powerline LAN (DLAN)

and.... it works well - no ip issues. everything ok.  Good news.

However, this means that I have to have the Modem and BT Hub together... The setup I would like is to have the BT Hub 3 away from the hallway (where the modem is) and in a cupboard....i.e. connected via DLAN.

So I guess the question is - Is this network topology possible and if so, how can I get it to work?

Once again... many many thanks for your continued help.
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Thanks for the advice.  Before I go off and buy another couple of DLANs - is there any way to do this via getting all my DLAN connected things (TV, Computer, Server) to use the DCHP on the BT Router?

Or must there be at least one connection into yellow Ethernet sockets (as shown here)?

Thanks again.
There must be a connection to the yellow ethernet socket. The thing in the closet is just a modem, not a router, the BT hub is the router.  So, you need a cable from the modem to to BT hub, then the yellow port to the rest of the network.

My guess is that you want to keep the BT hub closer to get better wireless signal strength? Another solution is to move the BT hub to the closet, avoid another DLAN device, but add an access point elsewhere in the home using existing DLAN.
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ok.  understood.  getting to the bottom of this and starting to regret not asking the BT engineer to move the master socket.  That would prevent all of this.

I guess my final thought is - would replacing the BT standard modem with a Modem Router be another solution?  Or is there likely be to something specific to the BT Infinity Modem that cannot be a simple replace....

I'm unfamiliar with the BT Infinity (hence some of my confusion in the thread above), and there may be some mincing of terms here.

What it appears is that BT is a fiber to the home/curb/etc service. The box in the closet, the
Huawei EchoLife is a modem (or in the case of fiber, some sort of optical network terminal). It takes the fiber cable from the street and converts it to "internet" but it does no NAT or routing functions. The BT hub you are provided is the router, which does NAT and routes your entire network.  Hence why the huawei needs to be connected to the BT hub then to the rest of the network (the inside/outside thing pergr was talking about).

I'm going to go out on a limb here and say that BT Infinity does not have a modem router combo device as it seems they give you both units. Another option may be to place a 3rd party router in the closet, and turn off the routing on the BT hub and leave it in the cupboard, or the access point or 2nd DLAN adapter as I mentioned above.

Certainly, there is no harm in contacting BT Infinity to make sure they don't have such a device, or offer any other alternatives.
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Dear All,

So I took the advice posted.  I purchased two new DLANs and created a secure connection between the modem and the router.  I purchased Solwise versions which provided me the software to configure it - this removed the hassle of the security button and waiting for the blinking of the light and wondering if the settings worked.

This then created a private connection and then with the other DLAN I connected to the ethernet port.

I now have fully working Wireless AND Powerline LAN (DLAN).

Many thanks for all the advice.  I would have spent hours playing with IP settings.

Very glad to hear its up and working :)

Hope the new DLAN kit didn't set you back too much cash.
Avatar of Angus


Actually... it wasn't too bad.  

This is what I ended up going for.

Thanks again
Not bad, even after converting to USD :)

Enjoy the fiber connection!