You can track the license usage of you vSphere environment by generating reports for the license usage of assets for a time period and vCenter Server system.
You can use the license reporting in vCenter Server for the following tasks:
View statistics about the license usage and capacity of products filtered by a vCenter Server system and time period.
Export license usage reports in a CSV format for further analysis and processing.
Set a threshold for the license usage of products with use-based licensing models, such as per-virtual machine. You can use license usage thresholds to receive notifications if a certain usage is exceeded.
The License Usage History service on vCenter Server takes snapshots of the license usage every hour. The license usage snapshots are stored in the vCenter Server database. A license usage snapshot contains data about the current license assignment and usage. The license usage information that you can view in the license reporting interface contains aggregated statistics from the snapshots that are collected in the period that you select.
The license usage reports that you can export in CSV format contain the raw data from the license usage snapshots that are collected in the period that you select.