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From: "Peter Bi" <mod_perl@att.net>
To: netfilter@lists.netfilter.org
Subject: Use netfilter to block DoS
Date: Sun, 27 Apr 2003 09:42:15 -0700	[thread overview]
Message-ID: <005d01c30cdb$f6883a80$6401a8c0@oc.cox.net> (raw)
In-Reply-To: E199mmm-0007tf-00@kashyyyk.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




  reply	other threads:[~2003-04-27 16:42 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2003-04-27 14:05 Port FW works form LAN but no from Internet ddougal
2003-04-27 16:42 ` Peter Bi [this message]
2003-04-27 18:16   ` Use netfilter to block DoS Dan Egli

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