Plesk

From diademblogs.com

Config Server Firewall (csf) and Login Failure Daemon (lfd) is a robust firewall solution having Stateful Packet Inspection (SPI), Login/Intrusion Detection and Security application for Linux servers. Although it is more compatible with CPanel we have been able to use the same for the Plesk hosting control panel also and it is running fine. Please visit the below link for more information.
From http://www.configserver.com

I have listed the installation steps for CSF / LFD.Login to your server with ‘root’ user and issue below commands :
Change directory to either /root or /usr/local/src , which ever you normally use for such installations
cd /usr/local/src
[Remove any old source that might be present]

Download and untar the source for installation
wget http://www.configserver.com/free/csf.tgz
tar -xzf csf.tgz

Run installation script
cd csf
sh install.sh

(more…)