How is OpsLogix VMware Management Pack licensed?

OpsLogix VMware Management Pack is licensed per physical Monitored ESX CPU Socket. The first year of support and assurance (SA) is mandatory and will be added to each socket upon purchase. Each sequential year, you will only be charged with the cost of software and assurance.

How to find the number of processors in your environment is described in this article:
KB: Find the number of processors sockets in your VMware environment