**** Moved to new discussion from https://vox.veritas.com/t5/NetBackup/Configure-Netbackup-master-media-server-on-virtual-machine/m-p/... ***
When we install netbackup master and media on VM machines, do we reuire to put any additional license other than the one we put for Physical master ?
Correct, a "license" does not need to be physically installed inside a client that is a guest VM, but this is missing the point.
I think you need to read the NetBackup Licensing Guide:
...because there is potential to make some very costly mistakes when making assumptions.