in 2008 and later we could use the terminal services configurator app to set drain mode when you wanted to take out a session host from a farm to do maintenance. in 2019 that configuration app is removed and I saw post pointing me to server manager. But I have no idea where to find that setting in the RDS role in Server Manager.
I know I can do a change logon /drain but I would rather use a GUI
Also, there is a company wide GPO enabling RD connections and that seems to interfere with the drain mode
"Connections are currently ENABLED by Group Policy for this machine, unable to change."
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