MySQL is not directly supported - as such for your backups of this data, you will have to be do some kind of dumpp out of my SQL, and then backup the files that the dump creates as flat files.
For Exchange you will need the App & DB agent as well as the BE 15 server edition - and this will allow you to backup the file systems of the Backup Exec server and the Exchange server with no further licenses needed. However if you have any other remote servers you will need further Agent for Windows licenses as well.
You have not mentioned if any of your systems are virtualized..... which might affect the answer. Note because you want to write to tape the Backup Exec server itself cannot be virtualized unless the tape system is a supported iSCSI device.
Depending on how many systems are involved, instead of a server license plus agent license you might find that Capacity or V-Ray editions are more cost effective - this choice is down to costs more than technology
Based on your description your current choices would be one of the following:
- BE 15 Server Edition with App & DB Agent (plus further Windows Agents if required)
- Capavity Lite Edition (costed in TB of full backups)
- Capacity Edition (costed in TB of full backups)
- V-Ray Edition (as long as your environment is virtualized not suitable if you have physical systems that need backing up. Costed against CPU count of the virtual hosts)
Suggest you review the licensing guide (attachment in http://www.veritas.com/docs/000024885 )
I would also recommend that you set the NAS up to provide an iSCSI LUN (if it has that capability) and attach that to the Backup Exec server - mainly because this is usually MUCH easier to configure against security access than a UNC share.