Our environment has some dedicated virtual machines acting as file servers only. The largest one still runs Server 2003, with three big virtual disk volumes. I'm beginning to deploy Server 2012 and one file-only server is working well, including file deduplication.
I would hand-copy files from one server to the other, but sysadmins are a lazy lot and I wondered if I could just detach a volume from the 2003 server, attach it to the 2012 server, and enable 2012 deduplication on it. I would then recreate the shares on the 2012 server and hope that the file system permissions remained in tact; both servers are domain members. I'd also have to edit logon scripts and home folders to point to the new mappings; no big deal there, and I'd have to do that anyway.
The underlying environment is vSphere 5.1, but I wouldn't expect the server VMs to behave differently if this were Hyper-V.
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