Date: Sun, 27 May 2001 17:59:31 +0200 From: Jens Schweikhardt <schweikh@schweikhardt.net> To: tlambert@primenet.com Cc: freebsd-current@freebsd.org Subject: Strange DNS behavior; I'm stumped Message-ID: <20010527175931.A729@schweikhardt.net>
next in thread | raw e-mail | index | archive | help
Terry,
thanks a lot for taking the time to attack my DNS problem.
I think, however, that there's something fishy with either
my DNS setup or FreeBSD's new nsswitch configuration.
# Make your test program do a gethostbyname(), like it does.
#
# Then take the resulting IP address, and call gethostbyaddr(),
# to get the _canonical_ name and IP address of the host you
# obtained by name, so that it will give you the A record name
# of the host, instead of some CNAMe which may be transient.
#
# Now watch your modem dial out, because you have not set up
# correct in-addr.arpa delegations for all of your local IP
# addresses in your DNS server.
#
# Now look up. See the lightbulb.
Hmm. Pardon my blindness, what I don't understand is that
1) My 4.3-RC#0 system does not show that behavior; it's configured
the old way with /etc/host.conf. Starting ctwm there does not
lead to the resolver doing a remote ns query.
2) The DNS query causing dial out requests an A record for
hal9000.schweikhardt.net. and not a reverse lookup for whatever.in-addr.arpa:
19:19:36.504837 IP 74: 213.7.20.247.1025 > 129.143.1.1.53: 34068+ A?
+hal9000.schweikhardt.net. (42)
In fact there is no reverse lookup among the first dozen or so packets.
3) The ctwm sources only have one call to gethostbyname(), none for
gethostbyaddr, so it's not as anal as one would think. The lines are
XmuGetHostname(client, MAXHOSTNAME);
hostname = gethostbyname(client);
I'm not sure if XmuGetHostname could be the culprit.
[Setting up a caching-only server]
Before I do that I want to track down what has changed. I still believe
that when my DNS works properly with 4.3 it should as well with 5.0
without jumping through this hoop.
Regards,
Jens
--
Jens Schweikhardt http://www.schweikhardt.net/
SIGSIG -- signature too long (core dumped)
To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-current" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20010527175931.A729>