[sagher]

@sagher

The error / warning message is pretty clear (at least in my humble opinion).

The installer tries to create a Let's Encrypt TLS certificate for your server based on the hostname of your server. The hostname of or your server is however a hostname that doesn't exist as a real domain or if it exists it is not pointed to the IP address of your VPS.

The best way to fix this would be to change the hostname of your VPS to a domain that you own and that is pointed to the IP address of your VPS. Or otherwise accept that a self signed TLS certificate will be used.

Yes i got it, but my confusion is that i got free cloudflare services and register domain from freenom. so the whole story is the freenom domains are bypass with cloudflare nameservers. and after this default process my domains are unable to respond. even i try to add them into myvestacp WEB domain add option. 

So i need to know that how to compile all NS and which is the criteria to got a working Domain at the end. 

Thank you