Using robocopy to mirror (with security) physical drive E: to iSCSI drive G: Once this is complete, I was planning to make sure there are no open file handles or sessions (it's a file share server) and then:
- Delete drive letter E:
- Rename drive letter G: to E:
At step #1, will the shares (upon which DFS is reliant) stay intact or will they get deleted/broken?
Yes the shares are associated with the drive letter and/or mount point.
I have used a procedure similar to that in the past when moving to a different type of storage. I replicate the data, stop the server service, shuffle the drive letters or mount points around, and restart the Server service.
You mention DFS, are you doing an DFS replication. I am pretty sure that drive letter swap would completely screw up replication, but I don't have any good references to support that belief. If you are only using DFS for namespace purposes then it shouldn't matter.