I'm planning to migrate a Windows Server 2012 R2 environment to Windows Server 2022. Does the order matter? Should I build the new domain controllers first, or migrate the member servers before dealing with the domain controllers? I'm looking for the safest approach and any compatibility checks I should make beforehand.
3 Answers
For member servers, the order is usually less critical, but test applications and dependencies as you go. If you choose in-place upgrades, verify the supported upgrade path for each server; some older versions require an intermediate release before reaching 2022. Fresh replacement servers are often less risky than upgrading production systems in place.
For the domain controllers, I’d avoid an in-place upgrade. Build new 2022 domain controllers, join them to the existing domain, promote them, verify that DNS and replication are healthy, and only then demote and remove the old controllers. In general, I’d handle the domain controllers first, then work through the member servers.
Before adding newer domain controllers, check which replication method SYSVOL uses. If the domain is still using FRS because it originated on a much older Windows Server release, you’ll need to migrate SYSVOL replication to DFSR first. Domains already using DFSR can generally add newer controllers directly, assuming the functional levels and prerequisites are supported.

The key rule is promote the replacement controller before demoting the older one. That gives you a rollback path and avoids running the domain without a functioning controller.