Subject: DNS lookup for internal adresses
To: None <firstname.lastname@example.org>
From: David TAILLANDIER <email@example.com>
Date: 03/07/2002 23:18:34
We have a LAN of several computers connected to the internet via a
NetBSD gateway. We don't have any DNS ; We only use our provider's DNS
to resolve internet adresses.
Our local network is 192.168.0.0/16
Nothing special as you can see.
Our internet provider have recently made a change to its DNS, and I
found it because... there is a problem now :-)
Their DNS *seems* to not answer anymore to reverse lookup requests like
"how is 192.168.0.199 ?". Since this change, when I log onto the
NetBSD gateway via SSH, it took several seconds before I can enter my
password because the NetBSD box wait the name of the computer I use
(and, since the provider's DNS drops requests for 192.168.0.0 ...).
And when I logged in, it tooks several seconds before a simple ping to
internal network to start. ping 192.168.0.x for example.
I think NetBSD send reverse lookup requests for every of thoses cases
and I have to wait for timeout. Around 2 minutes (!).
I then modified nsswitch.conf to explain NetBSD I don't want it to ask
anything to the DNS ("host: file" instead of "host: file dns").
All this because I very new into *nix familly.
Of course, I can't use DNS resolution anymore on the NetBSD box.
How can I tell the NetBSD box to use DNS reverse lookup only for
"real" internet adresses ?
Not for 192.168.0.0/24 or 10.0.0.0/8 (or what I want in fact because
we have some other LANs connected via 'vtun').
where can I find any documentation because it seems to be very hard to
find something written about NetBSD (or I'm too dumb to find it).
Many thanks from France :-)