For VDP 2TB appliance we need 3.1 TB free space in datastore.....my first question is why we need it more than 2TB and second question is can we increase that more than 3.1 TB.......is this supported by vmware?
Vmware only supported 2 TB..
Also check here..
VMware vSphere 5: Private Cloud Computing, Server and Data Center Virtualization
Your Oscar