firewalld installation and configuration under linux

Install firewalld: yum install firewalld
Add firewalld to system services: systemctl enable firewalld
Remove firewalld from system services: systemctl enable firewalld
Start firewalld: systemctl start firewalld
Close firewalld: systemctl stop firewalld
Check firewalld status, whether it is running: firewall-cmd - -state
permanently open port 8080: firewall-cmd --add-port=8080/tcp --permanent
View the configuration file cat /etc/firewalld/zones/public.xml
Reload firewalld to make the configuration take effect: firewall-cmd --reload