single dns query for A and AAAA

Phil Mayers p.mayers at imperial.ac.uk
Tue Feb 19 09:47:29 CET 2013


On 02/19/2013 07:46 AM, Havard Eidnes wrote:
>> So, i was wondering if anyone has compared the following two
>> scenarios in terms of speed, performance and IPv4v6/IPv4
>> preference:
>>
>> 2 simultaneous dns queries (a & aaaa)
>> 1 single dns query (any)
>>
>> I'm almost 100% sure that the "any" query will be too heavy for
>> many domains (esp with DNSSEC), [...]
>
> That's not the primary issue with that method.  The issue is that
> this will simply not work, for other reasons:

All correct; good explanation.

"any" is for debugging, not production queries. Google "qmail any" for 
an example of the hassle that using it this way can cause.


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