We are planning our 1st deployment of ZCM into a network that currently runs ZFD 7.

I am new to MS SQL and the licensing model is confusing to me so I was hoping someone could clarify.

We have approx 7,500 users and approx 3,000 workstations so multiple primary servers will deployed with one MS SQL server.

My question is, should we buy the SQL server + Device cals or SQL server + user cals?

If device cals, do I need a cal for each primary server?
if user cals, do I need cals for just the ZEN administrators?

thanks in advance.