6to4 in Internet aaaa records

Jeroen Massar jeroen at massar.ch
Fri Oct 3 04:31:25 CEST 2014

On 2014-10-02 22:24, Ca By wrote:
> Folks,
> What is the general impression of 6to4 addresses in AAAA records?
> I recently had a customer complain about this situation, and i am not
> sure, as a service provider, how to deal with it.
> From my home comcast connection with real full dual-stack, i get this 
> cbyrne at xxxx ~ $ wget -6 www.azdes.gov <http://www.azdes.gov>  
> --2014-10-02 19:19:48--  http://www.azdes.gov/
> Resolving www.azdes.gov <http://www.azdes.gov> (www.azdes.gov
> <http://www.azdes.gov>)... 2002::cf6c:8846

That is an invalid 6to4 address as it would have a 6to4 gateway of

One would think with all the "IPv6 consultants" in the US, that .gov
agencies would be able to get that part right...

Though, better point them out that 6to4 is a bad idea in general anyway.

I would not be surprised if the "DNS solution" generated that broken
address though as cf6c:8846 does map to which matches the
A record.


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