Forum Discussion
Any potential problems with mixed OS versions for Active Directory PDC?
Hi All, Just wanted to get people's opinions on the following: I have a customer with multiple sites, and 3 domain controllers. They also have a Microsoft volume license account so licensing...
Hello,
It is best to avoid mixing operating systems for DC - promoting even one triggers an Active Directory migration, and having older OSes put you at risk - expect security and compatibility issues. You also need to take admin tools into account (newer OS = newer admin tools).
Also, Active Directory migration isn't always straightforward - having on-premises Exchange will add prerequisites by example (and don't try to bypass - your Exchange infrastructure may explode).
My advice : do not try to go faster than you should.
Complete your file server migration first.
Make sure your DC own only AD and DNS roles and nothing else, and there is no other server with DNS role. Make sure you build them with Server Core.
Prepare a future Active Directory migration - check prerequisites (like DFSR), AD/DNS health and backup, enable optional features already available (like AD Recycle Bin), check new features available with newer OS and domain/forest levels.
Then, migrate your 2008 R2 to 2016. Enable new features and increase domain/forest levels (you won't need to do this on you reach 2016).
Then, trigger a global AD migration to 2022 using virtual machines if possible, or 2019 if you cant do better (end of support date for 2019 is slowly closing).
