Transparent DNS proxying on Telecom ADSL conection

Forums › Spark New Zealand › Transparent DNS proxying on Telecom ADSL conection

bertgt

8 posts

Wannabe Geek

Topic # 143791 27-Apr-2014 13:16

Hi,

Long time reader, first time poster.

I'm at my G/F's place and have had a bit of trouble accessing particular sites/things on the net. I decided to do some digging. Something very suspicious (and peculiar) is happening and I'm trying to figure out exactly what is being futzed with on her connection.

I'm currently trying to determine whether any transparent DNS proxying is being applied by Telecom. A simple way to test this is with the useful site DNSLeakTest.com

Trying to run a test using the router-assigned DNS servers result in the tests getting stuck before completing. If I use alternative DNS servers via a VPN (home is a SNAP connection, work is a DTS connection) there's no problem and the standard tests completes as expected.

Telecom staff members on Geekzone:

Can someone from Telecom confirm or deny whether transparent DNS proxying takes place please? If so, is there any disclosure that this takes place?

For other readers (Telecom customers):

Could you please do me a favour and point your browser to http://www.dnsleaktest.com and click the "Standard Test" button.
If the test completes you will be presented with a "Test Complete" heading on the page (plus some other stuff). Please advise if the test completes OK.

Optional details would also be helpful, consisting of:
Whether your IP allocation is dynamic or static.
Your location (city) in NZ.
The model of router/modem you have.
Your DNS servers (from your modem's broadband connection status page, not your PC/Mac.).

Thanks VM.

Bert

sbiddle

26634 posts

Uber Geek
+1 received by user: 6136

Moderator

Trusted

Biddle Corp

Lifetime subscriber

Reply # 1031997 27-Apr-2014 13:22

It might help to explain what problem you're trying to solve, and more importantly whether you're using the Telecom DHCP allocated DNS servers. If you're not you should be unless you fully understand the issues that will result from using something different.

If you're seeing issues loading pages the most obvious cause is the use of incorrect DNS servers, DNS proxying won't be the cause of such issues. Telecom will let you use any DNS you want, but if you're going to use DNS servers other than those handed out to you (which are geo balanced to ensure you get the best performance) you need to be weighting up the pros and cons of 3rd party servers.

Talkiet

3574 posts

Uber Geek
+1 received by user: 2087

Trusted

Spark NZ

Reply # 1032014 27-Apr-2014 14:24

Can someone from Telecom confirm or deny whether transparent DNS proxying takes place please? If so, is there any disclosure that this takes place?

No, and no, because there isn't.

How about explaining the issue you're having?

Cheers - N

nitrotech

1225 posts

Uber Geek
+1 received by user: 150

Reply # 1032036 27-Apr-2014 14:34

Not using a Technicolor router with windows 8.1 by chance? if so call telecom support and have it replace by a Huawei.

bertgt

8 posts

Wannabe Geek

Reply # 1032061 27-Apr-2014 14:43

Hi Steve, thanks for the reply.

My specific problem appears to be that certain hosts are not being resolved. NSLookup reports "non existent domain". In summary - When using Telecom's DNS servers, stuff doesn't work. When using another DNS server (connected via VPN to another network using other nameservers) (or Google's public ones) stuff does work.

The context of my post was in relation to Telecom's DNS servers (as this is a Telecom connection I'm on at present). The DNS server being used by my machine is the router (a TG585v8) and the router is forwarding DNS queries to dynamically assigned (presumably) Telecom DNS servers 122.56.237.1 and 210.55.111.1. Putting those two DNS servers into the TCP/IP settings of my machine manually does not resolve my problems. (i.e still using Telecom's DNS servers, but bypassing the router).

In summary, NSLookup and DIG fail to get results from Telecom's nameservers. I do get results querying Google's nameservers, or nameservers from an alt. ISP when connected to another network via a VPN.

Cheers
Bert

Talkiet

3574 posts

Uber Geek
+1 received by user: 2087

Trusted

Spark NZ

Reply # 1032062 27-Apr-2014 14:45

COuld you please supply some examples of domains that aren't being resolved by the Telecom DNS servers?

Cheers - N

bertgt

8 posts

Wannabe Geek

Reply # 1032065 27-Apr-2014 14:52

Hi Neil, thanks for responding.

Thank you for confirming that no proxying takes place.

At a high level, I guess the issue is that some DNS queries return empty (no) results when in fact I do know said host does exist.

As yet I can't provide any steps to reproduce, other than suggesting you try dnsleaktest.com and see whether or not the test completes OK. In my case it never completes when using Telecom's nameservers, but does complete when using nameservers from another network or when I tried Google's DNS servers. Therefore I can't really define the problem more specifically, or suggest what the cause of these problems is, other than perhaps erroneous DNS query caching.

Cheers,
Bert

Talkiet

3574 posts

Uber Geek
+1 received by user: 2087

Trusted

Spark NZ

Reply # 1032066 27-Apr-2014 14:56

bertgt: [snip]

As yet I can't provide any steps to reproduce, other than suggesting you try dnsleaktest.com and see whether or not the test completes OK. [snip]

How about some examples of the websites that you have issues with?

bertgt: I'm at my G/F's place and have had a bit of trouble accessing particular sites/things on the net.

Cheers - Neil G

bertgt

8 posts

Wannabe Geek

Reply # 1032067 27-Apr-2014 14:57

Hi Aaron,

As mentioned above it is a Thompson TG585v8. It is running FW 8.2.7.8.
I patched it with non-Telecom firmware a few months ago due to random issues I was once having with Google Drive causing the router to freeze.

Yes I know this voids any warranty etc.

What's the problem with the Technicolour routers and W8.1?

Cheers,
Bert