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From: Dan Egli <dan@shortcircuit.dyndns.org>
To: netfilter@lists.netfilter.org
Subject: Re: Use netfilter to block DoS
Date: Sun, 27 Apr 2003 12:16:35 -0600	[thread overview]
Message-ID: <3EAC1E83.6080907@shortcircuit.dyndns.org> (raw)
In-Reply-To: <005d01c30cdb$f6883a80$6401a8c0@oc.cox.net>

Peter Bi wrote:

>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
>  
>
I have a similiar rule, and I use ACCEPT.  I have my system configured 
to allow up to 5 ICMP messages per second. Beyond that they are dropped.
iptables -A INPUT -p icmp -m limit --limit 5/sec -j ACCEPT



      reply	other threads:[~2003-04-27 18:16 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 ` Use netfilter to block DoS Peter Bi
2003-04-27 18:16   ` Dan Egli [this message]

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