鉴于大量企业生产环境还在使用Centos 6，对照Centos 7把防火墙相关命令和问题一同记忆
| 防火墙 | centos7 | centos6 |
|---|---|---|
| 状态 | systemctl status firewalld.service | service iptable status |
| 关闭 | systemctl stop firewalld.service | servcie iptables stop |
| 禁止启动 | systemctl disable firewalld.service | chkconfig iptables off |
| 重启 | firewall-cmd --reload | iptables:service iptables restart |
| 开放端口 | firewall-cmd --zone=public --add-port=80/tcp --permanent | vi /etc/sysconfig/iptables -A RH-Firewall-1-INPUT -m state –state NEW -m tcp -p tcp –dport 80 -j ACCEPT |