VNXe storage systems have integrated deduplication support for file-based storage only (shared folders and NFS datastores). This feature is not available for iSCSI storage.
Does dedupe work with iSCSI generic storage?  I watched the video of someone at EMC (presumably anyways) setting up a shared folder with CIFS with the VNXe3100.  After he set up the volume, he had an option to turn dedupe on or off - along with a ton of other options.  Is this not available with iSCSI or is it just always on therefore not available to turn off? 
iSCSI Generic Storage and Deduplication