AAAA queries (was: Realtek 8139 (rl) very poor performance)

[Kevin Oberman]

> From: Imobach =?iso-8859-1?q?González_Sosa?= <imobachgs at banot.net>
> Date: Sat, 22 Jan 2005 02:37:49 +0000
> Sender: owner-freebsd-stable at freebsd.org
> 
> Thank you all for your responses and your support. However, I changed the 
> network card and it didn't work (I have now a Davicom 9102).
> 
> Well, anyway, after playing around with ethereal and tcpdump, I think that 
> the 
> problem have to do with IPv6. Well, not exactly. I found that when I try to
> make an HTTP connection (for example, with lynx), my machine sends an AAAA
> query and my DNS server doesn't seems to handle it properly.
> 
> So, I'd like the software stop doing such queries... what can I start for?
> Must I recompile aplications? I've get out "INET6" support from the kernel,
> but it's not sufficient.
> 
> Ideas? A link to documentation about it?

Have you used dig(1) or other diagnostic tools to confirm that your DNS
server is really not handling AAAA queries? This is really a a sign that
the DNS server is seriously broken. AAAA has been a standard for years
and any server that does not understand it is probably in very bad
shape.

Having (or not having) INET6 support is not relevant as the problem is
in the resolver. the queries may be sent as either INET6 or INET, but
either will ask for AAAA records. The problem is that any application
that is INET6 aware will make a call to the resolver for INET6 (AAAA)
resolution. Other than modifying the code or using an option to use only
INET, I'm afraid you are stuck. Many applications (finger, ssh, telnet,
...) have a -4 option to restrict the operation to INET.

But you really need to either get the nameserver fixed or find another
nameserver.
-- 
R. Kevin Oberman, Network Engineer
Energy Sciences Network (ESnet)
Ernest O. Lawrence Berkeley National Laboratory (Berkeley Lab)
E-mail: oberman at es.net			Phone: +1 510 486-8634