1、指令 vim /etc/sysconfig/iptables
添加以下内容和要开放的端口

Firewall configuration written by system-config-firewall

Manual customization of this file is not recommended.

*filter
:INPUT ACCEPT [0:0]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [0:0]
-A INPUT -s x.x.x.x/32 -i eth1 -j DROP
-A INPUT -s y.y.y.y/32 -d 10.45.185.47/32 -j ACCEPT
-A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
-A INPUT -p icmp -j ACCEPT
-A INPUT -i lo -j ACCEPT
-A INPUT -m state --state NEW -m tcp -p tcp --dport 80 -j ACCEPT
-A INPUT -j REJECT --reject-with icmp-host-prohibited
-A FORWARD -j REJECT --reject-with icmp-host-prohibited
COMMIT

###############保存iptables文件，重启服务###############

里面有禁止IP和允许IP的设置