If you run out of space on DFS replication target LUN you can’t simply provision another LUN and copy data over. Because it will change files attributes. There are two ways to preserve files metadata: use robocopy or NTBackup tool. But using robocopy is not recommended to pre-seed replicated folders in Windows Server 2003, because there are some issues in the version included in Windows Resource Kit Tools.
The way to go here is to use NTBackup. Remove the folder from DFS configuration first, to stop replication. Then backup the replicated folder and restore it to whatever LUN you want it to be on. To check that everything’s done right use dfsrdiag utility with filehash option. Dfsrdiag which is included in Windows Server 2003 doesn’t support filehash option. So you will most likely need to install recent RSAT tools for Windows 7 or Windows 8 on your desktop. Use dfsrdiag on several files and if it returns the same hashes, then it’s safe to assume that all other files were restored correctly too. Here is the example:
dfsrdiag filehash /path:”original path to the file”
dfsrdiag filehash /path:”path to the restored copy”
As the last step, add the new folder path to the DFS replication group. It will take some time for DFS to compare all the data. But if everything has been done right, only the delta will be replicated between members.
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