yum install firewalld
systemctl enable firewalld.service
systemctl disable firewalld.service
systemctl is-enabled firewalld.service
firewall-cmd --reload
firewall-cmd --completely-reload
firewall-cmd --permanent --zone=public --add-port=80/tcp
firewall-cmd --zone=public --query-port=80/tcp
firewall-cmd --permanent --zone=public --remove-port=80/tcp
firewall-cmd --zone=public --list-ports
firewall-cmd --permanent --zone=public --add-service=http
firewall-cmd --permanent --zone=public --remove-service=http
firewall-cmd --zone=public --list-services
firewall-cmd --get-services
firewall-cmd --list-all
firewall-cmd --zone=public --query-service=ssh
systemctl list-unit-files | grep enabled
systemctl --failed
firewall-cmd --get-active-zones
firewall-cmd --get-zone-of-interface=eth0
firewall-cmd --get-default-zone
firewall-cmd --panic-on
firewall-cmd --panic-off
firewall-cmd --query-panic
yum install firewall-config