Flood blocking

[Ashley M. Kirchner]

    I currently have one system I'm testing the following rules on:

    iptables -N SSHSCAN
    iptables -A INPUT -p tcp --dport 22 -m state --state NEW -j SSHSCAN
    iptables -A SSHSCAN -m recent --set --name SSH
    iptables -A SSHSCAN -m recent --update --seconds 300 --hitcount 2 
--name SSH -j DROP


    And just by watching it for the past few days, those rules seem to 
work pretty well.  So, it made me wonder, can I apply the same rules for 
FTP and e-mail (with the correct port information of course.)

    I get *a lot* of failed FTP attempts.  Especially when the sun comes 
up in Asia.  And then there's the e-mail spam that also doesn't stop.  
So, can I take those same set of rules above, replace the port number 
and name, and have them work for FTP and e-mail as well?

    Am I overlooking something really obvious?