防止dos攻击

#!/bin/bash
while [ 1 -eq 1 ] 
do
block_ip=`awk '{IP[$1]++} END{for (i in IP) {print i,IP[i]}}' /var/log/httpd/access_log | awk '$2>1000{print $1}'`
block_source=`firewall-cmd --zone=block --list-sources`
flag=0
for i in $block_ip
do
	flag2=1
	for j in $block_source
	do
	if [ "$i" == "$j" ];then
		flag2=0
		break
	fi
	done
	if [ $flag2 -eq 1 ];then
		echo "添加黑名单$i" >> black_ip.txt
		firewall-cmd --permanent --zone=block --add-source=$i >> black_ip.txt
		flag=1
	fi
done
if [ $flag -eq 1 ];then
	firewall-cmd --reload >> black_ip.txt
fi
sleep 2 
done