6to4 extinction (was: Re: 6to4 route at AS27552? (AS7922?))

Bjørn Mork bjorn at mork.no
Tue Nov 27 12:40:06 CET 2012

"Steinar H. Gunderson" <sesse at google.com> writes:
> 2012/11/10 Ivan Shmakov <oneingray at gmail.com>:
>>         Which makes me wonder on what are the costs of operating one's
>>         own “IPv6-to-6to4” relay?  As it seems, the “no valid route to
>>” case is much easier to troubleshoot that the
>>         converse “no valid route to 2002::/16” one, so the latter may
>>         indeed deserve some extra care.
> It's simple; if you wish, you can add a 6to4 decapsulation on every
> server if you wish. I've done it a few times, with a marked increase
> in reliability to 6to4-using hosts. (Nowadays it's quite irrelevant,
> though, since 6to4 is all but extinct.)

I stumble across this oddity from time to time, and it surprises me just
as much every time (which of course says a lot more about my memory than
anything else):

$ dig aaaa kernelnewbies.org

; <<>> DiG 9.7.3 <<>> aaaa kernelnewbies.org
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 2815
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 3, ADDITIONAL: 4

;kernelnewbies.org.             IN      AAAA

kernelnewbies.org.      3600    IN      AAAA    2002:4a5c:3b41:1:216:3eff:fe57:7f4

kernelnewbies.org.      3357    IN      NS      ns1.infradead.org.
kernelnewbies.org.      3357    IN      NS      mithlond.surriel.com.
kernelnewbies.org.      3357    IN      NS      ns1.sosdg.org.

ns1.infradead.org.      38346   IN      A
ns1.infradead.org.      38346   IN      AAAA    2001:770:15f::2
mithlond.surriel.com.   2329    IN      A
mithlond.surriel.com.   2329    IN      AAAA    2002:4a5c:3b41:1::65

;; Query time: 193 msec
;; WHEN: Tue Nov 27 12:32:22 2012
;; MSG SIZE  rcvd: 237

Yes, they still run dns, http and smtp services over 6to4.  Really.

Thought I'd just mention it here so that Google can find it for me the
next time it strikes me by surprise :-)


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