安裝iptables

# yum install iptables-services

# vim /etc/sysconfig/iptables
*filter
:INPUT ACCEPT [0:0]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [0:0]
-A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT
-A INPUT -p icmp -j ACCEPT
-A INPUT -i lo -j ACCEPT
-A INPUT -p tcp -m state --state NEW -m tcp --dport 22 -j ACCEPT
-A INPUT -p tcp -m state --state NEW -m tcp --dport 80 -j ACCEPT
-A INPUT -j REJECT --reject-with icmp-host-prohibited
-A FORWARD -j REJECT --reject-with icmp-host-prohibited
COMMIT
		

預設firewall作為防火牆的設置

#禁止firewall開機啟動

# systemctl disable firewalld.service

#設置防火牆開機啟動

# systemctl enable iptables.service 

#停止firewall 

# systemctl stop firewalld.service 

#重啟防火牆使配置生效

# systemctl restart iptables.service		
		
# chkconfig --level 345 iptables on
# service iptables start
		

Saving and Restoring IPTables Rules

# service iptables save
		

Firewall Policies