Configuring the Firewall
Access the server through SSH with an account with administrative privileges;
Open port TCP/443 on the local firewall with the following command:
# firewall-cmd --permanent --add-service=https
Stream also needs HTTP traffic allowed since it is required to set up the CRLDPs :
# firewall-cmd --permanent --add-service=http
To make the change effective, you need to restart the firewall service:
# systemctl restart firewalld