Last week, Microsoft introduced Windows Server Insider Preview version 17623, providing admins a preview on its upcoming Windows Server 2019 Long-term Servicing Channel (LTSC) release, scheduled for the second half of calendar year 2018.
While Microsoft strongly urges to validate the in-place upgrade functionality of Windows Server 2019 from Windows Server 2012 R2 and Windows Server 2016, one issue has already arisen in this area.
In‑place OS upgrade: Domain Controllers. During an in-place OS upgrade, Active Directory (AD) Domain Controllers (DC) might not be upgraded correctly. So, back up any AD DCs before performing an in-place OS upgrade.
I feel running a Windows Server Insider Preview build in a production environment to power your Active Directory Domain Controllers is only for a select few admins with a strong desire to feel alive again…. and have left Microsoft support far behind them.
However, in test and acceptance environments, this issue is something that might prove a challenge. It’s nothing new, however, since In-place upgrading an Active Directory Domain Controller to Windows Server build 17093 might also fail.