The NetBackup for NDMP license must be installed on the media server to use the hosts as storage units. Media Manager controls NDMP storage units but the units attach to NDMP hosts.
Create NDMP storage units for drives directly attached to NAS filers. Any drive that is attached to a NetBackup media server is considered a Media Manager storage unit, even if used for NDMP backups.
See the NetBackup for NDMP Administrator's Guide for more information.