Yesterday's Windows update causes IPv4 to be default

Sander Steffann sander at
Thu Nov 15 10:48:58 CET 2012


> The URL it tries to visit is, and
> searching the Internet for that FQDN yields some details of how it
> works.  If it can't retrieve the expected text at that URL, Windows 
> will order IPv6 to the bottom of its address preference table (by
> tweaking its internal RFC3484 rules).  The success (or failure) to
> get to that IPv6 site is remembered for that network for 30 days,
> and then re-tested.  I don't know how to encourage it to try a
> fresh test, but there must be a registry setting to force that to
> occur.

WTF? So one failure (either locally or of a Microsoft webserver) causes an IPv6 outage of one month... It will be 'interesting' to see internet traffic patterns shift for a month when has an outage...

I think this is a *very* bad design decision.

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