Believe it or not, there are still applications that require the use of a Raw Device Mapping (RDM) if you’re going to virtualize the machine it runs on. Recently I encountered a situation where the hard disk was already formatted as a Virtual Machine Disk format (VMDK) on a Virtual Machine File System (VMFS) datastore in VMware. In a previous article, I talked about converting an RDM to a VMDK; in this one, I cover the reverse process. I think the VMware KB article 3443266 on the subject is somewhat confusing, so I will attempt to explain the process in basic terms.
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