[(D)DoS Deflate] Script designed to block a denial of service attack
(D)DoS Deflate is a lightweight bash shell script  designed to assist in the process of blocking a denial of service  attack. It utilizes the command below to create a list of IP addresses  connected to the server, along with their total number of connections.  It is one of the simplest and easiest to install solutions at the  software level.
netstat -ntu | awk '{print $5}' | cut -d: -f1 | sort | uniq -c | sort -nIP addresses with over a pre-configured number of connections  are automatically blocked in the server's firewall, which can be direct  iptables or Advanced Policy Firewall (APF). (We highly recommend that  you use APF on your server in general, but deflate will work without  it.)
Notable Features
- It is possible to whitelist IP addresses, via /usr/local/ddos/ignore.ip.list.
 - Simple configuration file: /usr/local/ddos/ddos.conf
 - IP addresses are automatically unblocked after a preconfigured time limit (default: 600 seconds)
 - The script can run at a chosen frequency via the configuration file (default: 1 minute)
 - You can receive email alerts when IP addresses are blocked.
 
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