On Wed, 21 Apr 2004, Jeff Pitman wrote:
On Wednesday 21 April 2004 21:16, Nils O. Selåsdal wrote:
> On Wed, 2004-04-21 at 15:00, Jeff Pitman wrote:
> > be obnoxiously slow, both DNS lookups and simple "telnet
> >
www.google.com 80" tests.
>
> With ipv6 enabled, the libc resolver will afaik try to
> resolve hostnames as ipv6 addresses first. For alot of reasons
> that might take a long time..
> [...]
> So perhaps there should be(and maybe there is..) a way to say
> try ipv4 first in /etc/resolv.conf ?
This is interesting. However, the first hurdle is something deeper than
DNS because simple connects using "telnet x.x.x.x 80" takes longer
with IPv6 enabled. Editing /etc/modprobe.conf did the trick for me.
Have you looked with 'tcpdump -s 1500 -vvv -n' how the DNS packets
look like when you telenet to a host? Difference with earlier glibc's
etc.?
Guess 1: addition of getifaddrs() and detection whether v6 s enabled
or not in glibc may cause some problems, especially if kernel where
such glibc is used doesn't support it or vice versa.
(Guess 2..M): some other weirdness in glibc/kernel changes.
Guess M+1: you may be trying to connect to sites with broken DNS
load-balancers, see more and examples at:
http://www.watersprings.org/pub/id/draft-ietf-dnsop-misbehavior-against-a...
Guess M+2: you may be experiencing some other v6-related issue, see a
couple of issues at:
http://www.ietf.org/internet-drafts/draft-ietf-v6ops-v6onbydefault-01.txt
--
Pekka Savola "You each name yourselves king, yet the
Netcore Oy kingdom bleeds."
Systems. Networks. Security. -- George R.R. Martin: A Clash of Kings