CentOS 7 Open 3306 port access

CentOS 7.0 uses firewall as a firewall by default, and this is iptables firewall instead.
1. Close firewall:
Systemctl Stop Firewalld.service
Systemctl Disable Firewalld.service
Systemctl Mask Firewalld.service

2. Install iptables Firewall
Yum Install Iptables-services-y

3. Startup settings Firewall

# Systemctl Enable Iptables
# Systemctl Start iptables

4. View firewall status

Systemctl status Iptables

5 edit firewall, add port
Vi/etc/sysconfig/iptables #编辑防火墙配置文件
-A input-m state--state new-m tcp-p TCP--dport 22-j ACCEPT
-A input-m state--state new-m tcp-p TCP--dport 80-j ACCEPT
-A input-m state--state new-m tcp-p TCP--dport 3306-j ACCEPT
: wq! #保存退出

3. Reboot the configuration, reboot the system
Systemctl Restart Iptables.service #重启防火墙使配置生效
Systemctl Enable Iptables.service #设置防火墙开机启动