Hello there,
1)
Irrespective of the SQL server to be physical or on virtual server, you will require equal number of License keys as the number of SQL installation that you are backing. So if you have 2 servers (or VMs) which has SQL installed on it and if you would like to backup that SQL databases then you will require 2 Licenses of Microsoft SQL Agent.
If the SQL installation is on a Virtual machine then you will require the SQL Agent license only if you are going to use the Application GRT option. To use the Application GRT option you will require to install the Remote Agent on that particular VM. This Remote agent License need not be purchased as it will be included in the SQL Agent license.
So if you have 3 VM having SQL on it an if you would like to take the Application GRT backups so that individual SQL databases can be restored from the Virtual Machine backups then you will require 3 SQL Agent Licenses.
For more information on Licenses refer to "
http://seer.entsupport.symantec.com/docs/346039.htm " . In this article take a look at page no. 8, 9 , 10 to know more about Virtualisation License and Application GRT licensing.
2)
For the second query you can refer to the technote "
http://support.veritas.com/docs/312372 ".
AS per the technote you will have to Uncheck the option for
Exclude virtual machines that must be put in a saved state to back up and run the backups
3)
With the Licenses that you already have you will be able to :
a) Licenses Media server
b) Backup number of Virtual Machines hosted on 1 Hyper-V host
c) Backup Active Directory using this license which gives you the functionality to backup the GRT of AD.
d) With 2 Remote Agent Licenses you can backup two remote servers
e) With Exchange agent license you can backup Exchange Information Store. Install RAWS on the VM to take the Application GRT backups of Exchange if Exchange is installed on VM
f) With SQL agent license you can backup SQL Databases. Install RAWS on the VM to take the Application GRT backups of SQL if SQL is installed on VM