AT&T Uverse/DSL Network Engineer DNS question

Jonathan Lassoff jof at thejof.com
Tue Feb 5 21:13:50 UTC 2013


On Tue, Feb 5, 2013 at 1:10 PM, Jonathan Lassoff <jof at thejof.com> wrote:

> These appear to be an anycasted service, as I reach different destinations
> based on my source address.
>
> Hopefully each deployment has unique origin IPs for their recursive
> queries.
>

Just confirmed this. As these resolvers traverse and query your servers,
they'll have different source IPs, depending on the regional resolver.

Return differentiated DNS responses, based on that.

--j

>
> I would recommend against looking at RIR registration data to determine IP
> location. There's often little to no correlation, there.
>
> --j
>
>
> On Tue, Feb 5, 2013 at 1:01 PM, Tim Haak <thaitim43 at hotmail.com> wrote:
>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>> Hi,
>>
>>
>>
>>
>> Can a AT&T Uverse/DSL Network Engineer answer a question about the DNS
>> server IPs that are handed out to customers please? I am currently
>> testing from
>> a Florida IP. Can you please let me know if all Uverse and DSL customers
>> across the United States only use these 2 IPs as their primary and
>> secondary
>> DNS servers?
>>
>>
>>
>> 68.94.156.1
>>
>> 68.94.157.1
>>
>>
>>
>> We
>> provide services based on IP GEO-location. Since the 2 recursive resolvers
>> below are registered in Texas every DNS query for any of our records
>> return
>> results that are intended for IPs in that region. In other words, users
>> on the
>> east coast would actually resolve to a central part of the US or west
>> coast IP.
>>
>>
>>
>> Thanks
>> in advance,Tim
>>
>>
>>
>>
>
>
>



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