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Author Topic: how to drop syn  (Read 3456 times)

Offline klakshman03

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how to drop syn
« on: August 11, 2005, 05:54:18 AM »
Hi lnx... grp
    what is synflood and how it effects on servers and clients...

  iam using redhat linux9 for forwarding. i want to drop sysflood by using iptables ....pls suggest me

Offline Ricky

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how to drop syn
« Reply #1 on: August 11, 2005, 05:53:45 PM »
synflood is actually fake tcp/ip request to a machine which can turn it down on the network.. ie we can sa DoS attack.

about preventing it, you should wait for some expert to see this post . BTW.. just allow only those services which are required .

Offline sathish

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drop syn
« Reply #2 on: August 17, 2005, 12:24:56 PM »
Hai klakshman03

You can drop the syn floods by using the below mentioned code

iptables -A INPUT -p tcp ! --syn -m state --state NEW -j DROP

iptables -A INPUT -i eth0 -p tcp --syn -j DROP



Sathish.