check rules
| 1 | sudo iptables -L | 
clean rules
| 1 | sudo iptables -F | 
drop all
| 1 | # 关闭所有的 INPUT FORWARD OUTPUT 只对某些端口开放 | 
example
| 1 | iptables -A INPUT -p tcp --dport 22 -j ACCEPT #ssh | 
iptables config save
| 1 | su root | 
reload
| 1 | iptables-restore < /etc/iptables.up.rules |