Some weird DNS redirection on BT Infinity

It looks as though BT are intercepting DNS requests for Google (8.8.8.8) and OpenDNS and redirecting them to BT addresses which fail.
Basically Google services are unavailable if you want to use these DNS services and devices such as Chromecast with hardcoded DNS are useless.
I hope is is a bug and not part of the 'Snoopers charte'r implementation.

Have you tried hard coding the DNS e.g. 8.8.8.8 into a PC and seeing how it resolves.

Given BT are promoting Chromecast in offers to customers I very much doubt they have deliberately broken them.

This is lifted from the BT forum as I'm not at home but matches my experience.

Primary DNS: 208.67.222.222 (OpenDNS) or 8.8.8.8 (Google DNS)

tracert google.com
Tracing route to google.com [31.55.184.119] <- Incorrect BT IP address

BT default DNS:

tracert google.com
Tracing route to google.com [74.125.230.228] <- Correct Google IP address

It is working for me and others have reported too that it works over 3/4G or if I use a VPN.

Edited by smouty (Fri 28-Nov-14 12:03:28)

In reply to a post by smouty:

This is lifted from the BT forum as I'm not at home but matches my experience.

Primary DNS: 208.67.222.222 (OpenDNS) or 8.8.8.8 (Google DNS)

tracert google.com
Tracing route to google.com [31.55.184.119] <- Incorrect BT IP address

BT default DNS:

tracert google.com
Tracing route to google.com [74.125.230.228] <- Correct Google IP address

It is working for me and others have reported too that it works over 3/4G or if I use a VPN.

Have you tried going directly to 31.55.184.119 ?

That is Google.com ...


and any intercept that BT is undertaking will be done with the agreement of Google. Google has agreements in place with major ISPs to route traffic to them in specific ways that minimise loading on the ISP's and Google's networks.

Edited by MHC (Fri 28-Nov-14 12:21:18)

As is 216.50.208.32 also another Google.com IP address

i.e. Google.com appears on many different IP addresses and will be a LOT more than just one server in one location, hence the variation in IP addressing

I'm on BT Inifinity and using the Google DNS servers and that resolves to 74.125.230.128 using tracert. It also takes me to google.com if I enter the fixed IP address.

The address 31.55.184.119 is not reachable when using BT.
It is a BT owned IP which does point to Google.
It has been mentioned that BT may have an agreement much like they do with Netflix where the traffic stays within BT in some form of cache but basically it is broken.
Weird why it would route to an address outside of BT when using their own DNS though.

Edited by smouty (Fri 28-Nov-14 12:42:11)

It looks like a routing fault to me. It that address just where tracert stops, or is it the final destination address? What does the DNS address actually resolve to? It that's correct, then it's not DNS redirection, but IP redirection, which is rather a different thing. My suspicion is more towards a routing fault.

nb. DNS names do not necessarily resolve to the same IP address from every place and at every time. There are valid reasons why they resolved differently/

I can access it without problems from a BT connection and did so before I posted. Tracert works fine.

Lucky you.

There are a number of threads on the BT community but pretty much the same symptoms and like MHC, not everyone is affected as some people have reported that rebooting the modem and getting a new IP fixed it.

https://community.bt.com/t5/Other-Broadband-Queries/...

https://community.bt.com/t5/Other-Broadband-Queries/...

https://community.bt.com/t5/Other-Broadband-Queries/...