Recently I had a client whom I had migrated AD services from 2008 R2 to 2012 R2. That part of the project went well and when completed, I needed to upgrade their DFS infrastructure to 2008 Mode.
There were issues though and I had to do a few things that I didn’t really like to do. Let’s just say that when you have to use ADSIEDIT.MSC, it’s always a cause for concern!
Here are a few of the references that I used:
https://technet.microsoft.com/en-us/library/cc753875.aspx – procedure for upgraded DFS Namespaces to 2008 from 2000
https://social.technet.microsoft.com/Forums/office/en-US/d77b1057-7854-45a8-9449-20f64bcc2f48/tried-migrating-dfsr-namespace-from-2000-to-2008?forum=winserverfiles – Use ADSIEDIT.MSC to clean up DFS in AD.
https://blog.workinghardinit.work/2011/05/24/move-that-dfs-namespace-to-windows-2008-mode/ – Good article on the process
These are the steps that I took to upgrade the DFS with errors and the remediations that I found needed to be used.
1: Open an admin CMD prompt:
- Dfsutil root export \domain.localxyz c:xyz.xml
2: Write down the path for each namespace server:
3: In DFS Management, right-click the namespace and then click Delete
- Could not delete the entire DFS. Server03 gave an error about the element not being found – DFS – The namespace cannot be queried. Element not found
- Bounced the DFS services on all three DCs
- Able to delete the DFS Namespace but gave an error on Server03, red X on the namespace
- Deleted Namespace from the AD using ADSIEDIT.MSC
- Open ADSIedit.msc.
- Connect to Default Naming Context (the domain name)
- Expand and locate the container, which show the DFS root information
- CN=<name_of_the_DFS replication group>,CN=DFSR-GlobalSettings,CN=System,DC=<name_of_your_domain>
4: In DFS Management, recreate the namespace with the same name, but use the Windows Server 2008 mode
- At first, gave additional error about Server03 – Access is denied.
- Could not stop and restart DFS, access is denied
- Rebooted Server03
- Now about to stop and start DFS
- Added namespace back to the DFS successfully
5: Import the namespace from the export file
- Dfsutil root import merge c:pps.xml \Domain.localxyz
Now, all appears to be well.