说明：很多人搭建博客或者网站都会被DDOS攻击，基本都会出现网站打不开，服务器瘫痪，对于我们这些小博客来说，都不会花更多资金买抗DDOS服务器来防御DDOS，只能采取些其他办法，DDOS deflate是一款免费的用来防御和减轻DDOS攻击的脚本。它通过netstat监测跟踪创建大量网络连接的IP地址，在检测到某个结点超过预设的限制时，该程序会通过APF或IPTABLES禁止或阻挡这些IP。
1、安装DDOS deflate
http://www.moerats.com/usr/down/DDOS/deflate.sh chmod x deflate.sh ./deflate.sh
2、配置DDOS deflate
配置/usr/local/ddos/ddos.conf文件。
Paths of the script and other files PROGDIR="/usr/local/ddos" PROG="/usr/local/ddos/ddos.sh" IGNORE_IP_LIST="/usr/local/ddos/ignore.ip.list" CRON="/etc/cron.d/ddos.cron" APF="/etc/apf/apf" IPT="/sbin/iptables" frequency in minutes for running the script Caution: Every time this setting is changed, run the script with --cron option so that the new frequency takes effect FREQ=1 How many connections define a bad IP Indicate that below. NO_OF_CONNECTIONS=150 APF_BAN=1 (Make sure your APF version is atleast 0.96) APF_BAN=0 (Uses iptables for banning ips instead of APF) APF_BAN=0 KILL=0 (Bad IPs are'nt banned, good for interactive execution of script) KILL=1 (Recommended setting) KILL=1 An email is sent to the following address when an IP is banned. Blank would suppress sending of mails EMAIL_TO="root" Number of seconds the banned ip should remain in blacklist. BAN_PERIOD=600
标示说明：
NO_OF_CONNECTIONS=150最大连接数，超过会被屏蔽，默认即可
APF_BAN 默认是1，建议使用0，标示iptables限制
EMAIL_TO=""填写邮箱账号，到时候有信息会发送到我们邮箱中
BAN_PERIOD=600 代表限制该IP 600秒
