Subject: Re: Unexpected AAAA queries
To: der Mouse <>
From: Thomas Seeger <>
List: tech-net
Date: 07/13/2003 19:03:54
>> While using NetBSD on an i386 machine I experience large delays in
>> http/ftp/etc. connections:  [...tcpdump showing AAAA queries...]
> The resolver library is trying to do IPv6 lookups.  (It
> doesn't realize, at this point, that it can't do v6 connections, and
> indeed, I'm not sure it should; it's perfectly reasonable to do a v6
> address lookup on a v4-only host.)
> I'd be more inclined to address the question of why they're
> going unanswered.  What DNS server are you using?

The DNS server on bummi is WinRoute 4.2, configured as a caching forwarder.
For some reasons there is at the moment no chance to switch over to another
routing software (and OS...). As a fix I'm now using the name server at my
ISP instead the WinRoute forwarder. Its somewhat ticklish that all flavors
of Windoze show no problems with WinRoutes forwarder. As a test I booted a
life-on-CD Linux (Knoppix), tcpdumped, voila, no problems, no AAAA queries.
The matter reminds me of the pmtud/mssclamp discussion..... Would be nice if
the NetBSD resolver showed some more robustness to the real world. How about
the resolver DOES realize it cant do v6 lookups and stops fiddling around
with AAAA requests?

Thanks for the help!