Ondrej Žilinec – IT Blog

Problem: One of our customer has about 30 locations across our country and they wanted to use DFSR to replicate folder content to all locations. At each location there is one Hyper-V host running Windows Server 2012 R2 OS with DFSR installed. Each server has three disks – C:\, D:\ and E:\. I have configured DFS Replication in DFS console, replicated AD across environment, and … and nothing happened. DFSR didn’t do anything. It did NOT even create its own private folders in “System Volume Information” folder. No error event in Event viewer. DFSR was set to replicate folder on disk D:\ – didn’t work. I tried to replicate directory on E:\ disk – didn’t work. So I tried to replicate folder on C:\ disk – it did work 🙂

Solution: I enabled DFSR debug logging. There was no error mentioned, but what I noticed was that disks D:\ and E:\ had same serial numbers and also same volume IDs. It was weird. But after some discussion I found out that those two disks were “copied” and “cloned” in Hyper-V environment. So that’s why they had same serial numbers and volume IDs. I found out that it can be a problem. So I had to change volume ID using Microsoft utility VolumeID. After I changed one disk volume ID and rebooted system, DFSR started to work as expected.

So never do disk cloning. Or if you do, change at least volume ID for those disks so Windows services don’t get confused. Looking into this problem took me one and half day! Thank you Microsoft 🙂