In our company we are planning to do Windows 2008 R2 migration due to End of Support it reached. We're not that fans of living on edge but this time it appear to be wiser target to Windows Server 2019, not 2016 (so we'll live with for years further).
While reading on this topic and looking for best practice approaches I can see many people recommend to do step-by-step migration (2008R2 -> 2012 -> 2016 -> 2019), but in our case it appears to be very lengthy and error-prone way, isn't it? At the same time, looks like we can do that in one giant step (2008R2 -> 2019) so I would like to ask your advice, is it true?
Best Answer
If you want to upgrade the actual servers by performing an in-place upgrade (which I highly advise against), you need to go through multiple steps.
But if you want to add new 2019 Domain Controllers to replace the existing ones, then yes, you can definitely add 2019 DCs in a 2008R2 domain, after the standard preparatory steps (adprep).
Also make sure your SYSVOL uses DFS replication instead of FRS; which it should, but sometimes FRS just stays there because nobody bothered changing that after upgrading from 2003. FRS is not supported anymore and you can't add a 2019 DC in domain which still uses it.
Also, take extra care if you have non-Windows (or old Windows such as XP) devices that use Active Directory for authentication; they might be not compatible with 2019 DCs due to their stronger security settings.