migration from server 2008 to 2012 R2 using Robocopy

I have old file server running Server 2008 and I have new file server that will be replaced it running 2012 R2. They’re both under the same AD .

I have copied one share already using: robocopy sourceshare destinationshare /mir /sec /secfix

It applied permissions to the root share but not the subfolders, which is an issue. How do I copy permissions and have them stick to every subfolder/file under the main share?

Also, is there a way to duplicate the data drive entirely? Instead of going share by share, if I want to copy the entire contents of D drive on source to E drive on destination, along with permissions, can I use robocopy to do this?