Centos抵御DDOS的简单手法
#iptables -A INPUT -p tcp –syn -m limit –limit 1/s -j ACCEPT
#iptables -A INPUT -p tcp –tcp-flags SYN,ACK,FIN,RST RST -m limit –limit 1/s -j ACCEPT
#iptables -A INPUT -p icmp –icmp-type echo-request -m limit –limit 1/s -j ACCEPT
#echo 2048 > /proc/sys/net/ipv4/tcp_max_syn_backlog
#echo 1 > /proc/sys/net/ipv4/tcp_synack_retries
#echo 1 > /proc/sys/net/ipv4/tcp_syn_retries
#echo 1 > /proc/sys/net/ipv4/tcp_syncookies
