From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Peter Bi" <mod_perl@att.net>
Subject: Use netfilter to block DoS
Date: Sun, 27 Apr 2003 09:42:15 -0700
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To: netfilter@lists.netfilter.org

Hi,

I have two questions related to Denial of Service:

1) If I want to set up a syn-flood protection, based on 1 per second (bursts
5), should I use

iptables -A INPUT -p tcp --syn -m limit --limit 1/s -j DROP
or
iptables -A INPUT -p tcp --syn -m limit --limit 1/s -j ACCEPT

The first one seems to drop those which EXCEED 1 per second
and the seocnd one seems to accept which is WITHIN 1 per second (so the
exceptions are dropped).
confused in logic :-(

2) where can I find more information on the use of Netfilter to DoS ?

Thanks.

Peter