firewalld sudo firewall-cmd --get-default-zone sudo firewall-cmd --set-default-zone=internal sudo firewall-cmd --get-active-zones sudo firewall-cmd --list-all-zones 換腳 firewal-cmd --permanent --zone=public --remove-interface=ens34 firewall-cmd --permanent --zone=internal --add-interface=ens34 Allow / Deney port sudo firewall-cmd --zone=public --add-port=12345/tcp --permanent sudo firewall-cmd --zone=public --remove-port=12345/tcp --permanent Introduction to FirewallD on CentOS