Re: Server under DDOS attack HELP

James Turnbull <[email protected]> Sat, 14 Aug 2004 22:20:21 +1000
Newsgroups org.kernel.vger.linux-config,org.kernel.vger.linux-admin
Message-ID <[email protected]>
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Kev wrote:

>hi,
>
>for the 5th time today my server is under a DDOS attack :( how can i
>stop this ??? what i block all ICMP communication ?????
>
>plz help.....
>
>  
>
Kev

What sort of attack is this?  What are you seeing in your firewall logs?

To restrict all incoming new and established state ICMP traffic you can 
do something like:

iptables -A INPUT -p icmp -m state --state NEW,ESTABLISHED,RELATED -j DROP

Regards

James

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