HOWTO: CSF Firewall + LFD Login Failure Daemon
The following is a guide to installing ConfigServer Services' firewall and login failure daemon.

Warning: The Latest version of CSF does not work properly with DirectAdmin on CentOS 5 machines with Apache 2+

CSF + LFD is a full security suite. I have provided a list of the features that I have personally tested and have made work on a DirectAdmin server. I will include this list at the bottom of this post.

CSF + LFD have most of the functions APF provides, and more security features and brute force detection tools than BFD provides. It provides protection for small-scale DDoS attacks and SYN flood protection. A script to uninstall APF and BFD is included.

To install:

First, check to make sure there are no existing copies of csf in the folder:

Code:
rm -fv csf.tgz
Then:
Code:
wget http://www.configserver.com/free/csf.tgz
tar -xzf csf.tgz
cd csf
sh install.sh
CSF has now been installed at etc/csf

If you have APF and BFD installed you must remove them:
Code:
sh /etc/csf/remove_apf_bfd.sh
By default, the firewall is set to testing mode and many of the features are turned off. To turn your firewall on and modify the settings edit up your csf.conf file located in:
Code:
cd /etc/csf
I've created a generic csf.conf file that you may download from our server. This file will work on most DirectAdmin installations. I have only checked it on CentOS. Delete your current csf.conf file and:
Code:
cd etc/csf
wget http://oakdns.net/downloads/csf.conf
Be sure to chmod the conf file to 600 once you have downloaded it and change the following line:
Code:
TESTING = "1"
to
Code:
TESTING = "0"
Finally, turn the firewall on:

Code:
/usr/sbin/csf -s
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http://www.directadmin.com/forum/showthread.php?t=27315&page=1