I would like to expose you my situation and ask for the best license to buy.
I am actually using a vmware server and veeam 7 to backup. I have no subscription. I have in my mind to completely change everything. I would like to buy two Dell PowerEdge R630 and make them in High Availability, working together on the same NAS. In case of disaster on a machine, the other will take it place. I will have a second NAS to replicate the other. I would like to use Veeam in order to perform regular backup of the servers (working as a single server). Am i able to buy a new Veeam Essential License in order to perform backups of this structure? Does it cover both servers (2 cores each)?