I have moved your query in https://vox.veritas.com/t5/NetBackup-Appliance/5230-Cannot-Start-NBFSD-following-2-7-2-upgrade/m-p/7... to a new discussion.
Please give us all the details of your environment.
The solution was simple:
Install the role of NFS in the Master as in the client, just there I could make the granular backup of AD without errors.
This is the order that you use:
* Install NFS Server and NFS client on Media Server, this to use GRT backups
* Install NFS client in the clients that want to use GRT
Thanks to you.