Yahoo and IPv6

Mark Andrews marka at
Wed May 11 00:19:17 UTC 2011

In message <alpine.BSF.2.00.1105101608140.19724 at>, Jason Fesler wr
> > Of course I'm assuming individual participants will do stuff, but that 
> > doesn't change that this IPv6 day as it stands now is a one-off event,
> > not the first step towards the Ultimate Goal.
> The intent is to get folks together after we digest the data, to talk 
> about next steps.  Date is not yet picked.
> I'm hoping we collectively prove there is no broken user problem.  I 
> realistically expect we'll have another "v6d" - either as 24h, or as a 
> roll-on-and-stick.   But, until we get through the day, and analyze the 
> data, any decisions on what to do next are premature.
> The NANOG following v6d should be interesting; I'm hoping a number of 
> folks from both access and content are willing to share any early stats 
> they have.

What I would like OS and application vendors to do is test every
network product they ship with 3 sets dual stack servers which are

* With the service on both IPv4 and IPv6.
* With the service on IPv4 and the IPv6 service silently blocked.
* With the service on IPv6 and the IPv4 service silently blocked.

If the product is designed to work on a dual stack client it should
work correctly though perhaps slowly with the server configured in
all three of these states.  This isn't hard and is just basic quality
control.  And for Apple, don't forget to prime the address cache
so that both A and AAAA records are present.  There is no excuse
for any vendor to be currently shipping products that fail such a

For the record Apple's current iChat (the OS (10.6.7) is completely
up to date) fails such a test.  It will try IPv6 and not fallback
to IPv4.  End users shouldn't be seeing these sorts of errors.

Yes, this is name and shame.
Yes, I have reported this to Apple through their web site.

Mark Andrews, ISC
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742                 INTERNET: marka at

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