AAAA's for www.netflix.com

David Temkin dave at temk.in
Fri Jun 8 04:31:22 UTC 2012


On 6/7/12 10:23 PM, Daniel Roesen wrote:
> On Fri, Jun 08, 2012 at 12:11:20PM +1000, Mark Andrews wrote:
>>> $ dig @pdns3.ultradns.org www.netflix.com. A +norec +short
>>> wwwservice--frontend-313423742.us-east-1.elb.amazonaws.com.
>>> $ dig @pdns3.ultradns.org www.netflix.com. AAAA +norec +short
>>> dualstack.wwwservice--frontend-313423742.us-east-1.elb.amazonaws.com.
>>> $ dig @pdns3.ultradns.org www.netflix.com. ANY +short +norec
>>> $
>>>
>>> Resolving www.netflix.com using ANY RRtype fails with an empty answer
>>> section in the DNS response.
>> Which is just plain BROKEN.
> Yup.
>
>>> This DNS trickery seems to be from the "taking a shower, trying not
>>> to get wet" department. And has adverse effects in corner cases. While
>>> playing around, I had periods of time where I couldn't resolve the FQDN
>>> at all, possibly due some caching of the empty response.
>> It's not DNS trickery.
> The "trickery" is returning different CNAMEs for QTYPE=A and QTYPE=AAAA.
> I'm not sure what's the goal of that is, but it's 4am here so I have an
> excuse of not seeing the light. :)
>
> Best regards,
> Daniel
>
We've confirmed that UltraDNS had "additional" issues caused by the push 
that they fixed for the previously reported problem.  We are actively 
engaged with them to come to a resolution.

-Dave




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