Backward compatibility for Widows 2016 Domain Controller

Question

Hi Folks,

We have current environment with Windows 2008R2 and Windows 2012R2 Domain Controllers.
90% of client environment is running with Windows 7 VDI.
We are in process of replacing all Windows 2008R2 Domain controllers with Windows 2016 Domain Controllers.
Just wanted check what all compatibility issues we need to take care of and are there any known issues in this?
We do have member Servers with Windows 2008 R2, 2012R2 and 2016.
File Servers with DFS based share.
Appreciate any in put in this regard.

Regards
Mahesh

Answer 1

Windows 7 defaults to SMB2.
https://learn.microsoft.com/en-us/windows-server/storage/file-server/troubleshoot/detect-enable-and-disable-smbv1-v2-v3

Shouldn't be a problem though I'd recommend the extended security updates for Windows 7/ 2008 members.
https://www.microsoft.com/en-us/windows-server/extended-security-updates

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Answer 2

Shouldn't be a problem.

• The two prerequisites to introducing the first 2019 domain controller are that domain functional level needs to be 2008 or higher and older sysvol FRS replication needs to have been migrated to DFSR
  https://techcommunity.microsoft.com/t5/Storage-at-Microsoft/Streamlined-Migration-of-FRS-to-DFSR-SYSVOL/ba-p/425405
• The prerequisite before introducing the first 2016 domain controller: domain functional level needs to be 2003 or higher

I'd use dcdiag / repadmin tools to verify health correcting all errors found before starting any operations. Then stand up the new 2016, patch it fully, license it, join existing domain, add active directory domain services, promote it also making it a GC (recommended), transfer FSMO roles over (optional), transfer pdc emulator role (optional), use dcdiag / repadmin tools to again verify health, when all is good you can decommission / demote old one.

Also at some point either before or after (if it hasn't been done) I'd recommend migrating sysvol replication from older FRS technology to DFSR
https://techcommunity.microsoft.com/t5/Storage-at-Microsoft/Streamlined-Migration-of-FRS-to-DFSR-SYSVOL/ba-p/425405

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Answer 3

Thanks Patrick
How about compatibility on legacy clients like Windows7?
Understand that Windows 2016 enforces SMB2 rather than SMB1 in legacy clients.
Are there any issues in replication partners with legacy domain controllers like Windows 2008R2.
Any issues in Legacy DFSNamespace after introducing Windows 2016 DCs?

Regards
Mahesh

Answer 4

Just upgrade some windows 2012 R2 DC to windows 2016 and 2019. I don't see any issues. However, FRS need to convert to DFSR. Step by step instruction can be found here:

Windows Server Upgrade - Step by step with screenshots