(D)DoS Deflate

(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 -n
IP 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.

Installation

wget http://www.inetbase.com/scripts/ddos/install.sh
chmod 0700 install.sh
./install.sh

Uninstallation

wget http://www.inetbase.com/scripts/ddos/uninstall.ddos
chmod 0700 uninstall.ddos
./uninstall.ddos

Sau khi cài đặt thành công, ta có thể cấu hình Firewall bằng cách dùng lệnh:

nano /usr/local/ddos/ddos.conf

Đây là file cấu hình của Firewall, nội dung cơ bản sẽ như sau:

FREQ=1 // tắt/ bật Firewall (0=tắt, 1=bật)
NO_OF_CONNECTIONS=50 // max connect từ 1 IP đến server
APF_BAN=1
KILL=1 // tắt/bật (0=tắt, 1= bật)
EMAIL_TO="administrator@techblog.vn"
BAN_PERIOD=600 // thời gian ban IP là 600 giây


Questions?

Although most things are explained on this page, if you have any further questions, you may contact the original developer of the script, Zaf.

Nhận xét

Bài đăng phổ biến từ blog này

Code chống iframe

Hướng dẫn cài đặt và cấu hình PHP Zend OPcache trên CentOS

Code đặt mật khẩu cho file PHP