Hello,
Thank you so much for posting here.
So sorry that we are not professional with Linux SAMBA Active Directory.
Similar discussion is here.
https://superuser.com/questions/1481039/does-windows-server-2019-essentials-have-to-be-a-domain-controller-as-requiremen#:~:text=The%20Microsoft%20blog%20Windows%20Server,with%20other%20Active%20Directory%20domains.
We could add it as member server or configured it as domain controller.
"If configured as a Domain Controller, Windows Server 2019 Essentials must be the only Domain Controller, must run all Flexible Single Master Operations (FSMO) roles, and cannot have two-way trusts with other Active Directory domains."
Best regards,
Hannah Xiong
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