Hi. At 10.9.1 you don’t need to put the https or the port number it’s just the fully qualified domain name of the proposed hosting server:
hostname.domain.com
do not use the web adaptor address. It’s purely the name of the host machine.
also make sure you’re using the primary site admin account for the server. Don’t use portal credentials?
also have you opened up all the firewalls?
Scott Tansley
https://www.linkedin.com/in/scotttansley/