查看 firewall 服务状态：systemctl status firewalld
查看 firewall 的状态：firewall-cmd –state
查看防火墙规则：firewall-cmd –list-all
查询端口是否开放：firewall-cmd –query-port=19999/tcp
开放 19999 端口：firewall-cmd –permanent –add-port=19999/tcp
移除端口：firewall-cmd –permanent –remove-port=8080/tcp
重启防火墙 (修改配置后要重启防火墙)：firewall-cmd –reload
正文完