From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Mark E. Donaldson" <markee@bandwidthco.com>
Subject: RE: Question about REJECT in FORWARD rule
Date: Wed, 11 Aug 2004 18:32:44 -0700
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To: 'Carlos Villegas' <villegas@math.gatech.edu>, 'Jason Opperisano' <Jopperisano@alphanumeric.com>
Cc: netfilter@lists.netfilter.org

 
Really? I thought "-j REJECT --reject-with tcp-reset" would always do the
right thing, even without specifying --syn (of course, it wouldn't be a bad
idea to specify it anyway). I have several systems running fine without the
--syn option explicitly mentioned. Could any of the "core"
guys say if my assumption is wrong? 

Carlos


My views are this: If you are going to reset a TCP connection, it is best to
do so at the earliest possible moment of a TCP session, preferably after the
initial syn of the three-way handshake. When I use "-j REJECT --reject-with
tcp-reset" it is always in response to a NEW (thus syn) packet. Perhaps Mr.
Stone will weigh in on this. If Chris Brenton is listening in, I would like
to hear his views on this as well.