[Samba] Cannot authenticate the administrator account

[Mike]

Andrey, thanks for your help.
It's discouraging getting stuck on these fundamentals, not making progress.

Can you tell me how I would provision the following:

hostnamectl status reports:

Static hostname:  a10
The registered FQDN is:  mwllc.info
I'd like to name the domain on the samba server:  conpago.mwllc.info
The static IP on the CentOS Samba box is set to:  10.10.1.225.
Using INTERNAL_DNS setting and dns forwarder is set to my ISP's
nameserver:  75.75.76.76

What's the correct provisioning parameters?

Thank you for your patience.

Mike