Ned here. Our developer team colleagues at the File Cabinet have posted an interesting article on the DFSDIAG tool. Introduced with Windows Server 2008, this utility is excellent for testing, documenting, and troubleshooting your DFS Namespaces environment. Make sure you give the article a read.

What Does DFSDIAG Do? (FileCabinet Blog) 

PS: not be confused with the DFSRDIAG tool, which is used with DFSR. Don't worry, I do it all the time myself. :-)

- Ned Pyle