systemctl status firewall

systemctl start firewalld

systemctl disable firewalld

systemctl stop firewalld

firewalld-cmd --state

firewalld-cmd --zone=public --list-ports

firewalld-cmd --reload

netstat -tlunp

iptables-save

firewall-cmd --zone=public --add-port=22122/tcp --permanent

--permanent表示永久开放，

firewall-cmd --reload

iptables-save