It is recommended that all of your V-Ray licenses be programmed onto a single licensing dongle, which can be plugged into a central server and accessed over the network. This is the most streamlined and user-friendly option, however it is also possible to program single V-Ray licenses onto individual dongles if that best suits your needs.

Please visit the Chaos Group Licensing page for more information on V-Ray 3.0 licensing: V-Ray 3.0 Licensing FAQs