I’ve added the GUI to Ubuntu Server 20.04 (below), and after that I lost access to Cyberpanel login page. SSH to the VPS is working fine.
I’ve seen few posts and I found out that the problem was with CyberPanel Firewall
If I stop CyberPanel FW (below) then I can access CyberPanel
systemctl stop firewalld
But if I access CPanel and re-enable the Firewall I lose access to CPanel again.
So, how do I change Firewall ports via SSH?
systemctl status lscpd ** OK, Running
Cloudflare DNS ** DNS Only
Add Ubuntu GUI
OK, I found the workaround for those who may be interested, enter these lines via SSH, then access CPanel with port number 1234:
systemctl start firewalld
systemctl enable firewalld
sudo firewall-cmd --permanent --add-port=1234/tcp
note: firewalld is the firewall used by CPanel.