centos配置防火墙 开启80端口 
编辑配置文件/etc/sysconfig/iptables

[root@weixinht ~]# vim /etc/sysconfig/iptables 

    1 # Firewall configuration written by system-config-firewall
      2 # Manual customization of this file is not recommended.
      3 *filter
      4 :INPUT ACCEPT [0:0]
      5 :FORWARD ACCEPT [0:0]
      6 :OUTPUT ACCEPT [0:0]
      7 -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
      8 -A INPUT -p icmp -j ACCEPT
      9 -A INPUT -i lo -j ACCEPT
     10 -A INPUT -m state --state NEW -m tcp -p tcp --dport 22 -j ACCEPT
     11 
     12 -A INPUT -m state --state NEW -m tcp -p tcp --dport 80 -j ACCEPT
     13 
     14 -A INPUT -j REJECT --reject-with icmp-host-prohibited
     15 -A INPUT -j REJECT --reject-with icmp-host-prohibited
     16 -A FORWARD -j REJECT --reject-with icmp-host-prohibited
     17 COMMIT

修改的部分：  在第10行22端口规则的下面增加 80端口规则  编辑时直接y复制一行再p粘贴， 22改为80

/etc/init.d/iptables restart 

重启防火墙使配置生效