@BlueSkyTech
I find it disappointing that your reseller could not answer your licensing query.
You may want to try to locate a knowledgeable partner on Veritas Partner Locator.
The BE license that you have found is the bare minimum to get you going -
The server license is needed for the BE Media Server.
This license also allows for backups of filesystems on the BE Server.
Backup to disk is included if you want to use the NAS as backup storage (target).
If you want to backup other servers on the network, you will need additional licenses -
Windows Agent (for file-level backups)
Agent for App & DB (for supported Apps and DBs)
If virtual systems in the environment, - Agent for VMware and Hyper-V
etc.
etc.
The alternative to individual agents and options is Capacity license (there are 3 different editions).
You purchase sufficient TB to protect all data on the servers in your environment.
Please find the BE Licensing Guide and other helpful info here: https://www.veritas.com/support/en_US/article.100032497.html
Backup Exec 20.x Licensing Guide
