From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jason Opperisano <opie@817west.com>
Subject: RE: How to block only MX query made to DNS server
Date: Sun, 28 Nov 2004 01:21:46 -0500
Message-ID: <1101622905.10064.29.camel@hubcap.ljm.dom>
References: <20041128041755.17971.qmail@web12307.mail.yahoo.com>
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On Sat, 2004-11-27 at 23:17, pravin rane wrote:
> That is right but only when all clients are using my
> DNS server. I will not be able to block MX requests if
> they are using some other DNS servers which are
> out-side of my network and I can not force my clients
> to use only my DNS server.

iptables -t nat -A PREROUTING -i $INSIDE_IF -p udp \
  --dport 53 -j REDIRECT --to-port 53

or some variant thereof...

-j

--
"Lisa, if the Bible has taught us nothing else, and it hasn't, it's
 that girls should stick to girls sports, such as hot oil wrestling
 and foxy boxing and such and such."
	--The Simpsons