Virtual Machines and License Analytics

License Analytics uses information gathered by the virtual environment discovery process to evaluate the relationships between virtual machine hosts and guests.

  • VM host: A virtual machine host is a hardware device that runs virtual machines (guests). A VM host may run a copy of Windows, a hypervisor (such as Hyper-V or VMware), or another operating environment entirely.
  • VM guest: A VM guest runs its own copy of an operating system and applications. A VM guest may run a Windows desktop title, Windows Server, Linux, or some other operating system.

The virtual environment discovery process will usually return information on the operating systems or virtual environments related to each VM host, including the name of the operating system and the license channel (not available for many versions of SQL Server) with which it was installed, and whether the virtual machine was running at the time the virtual environment discovery occurred.

License Analytics ignores virtual machines that are not running, and ignores all host and virtual machines that are not running a copy of Windows (desktop or server).

Windows Desktop Titles and Virtual Machines

As a general rule, every copy of a Windows desktop operating system (Windows 7, Windows 8, and so forth) requires its own license. Example: If you have a VMware host running ten copies of Windows 7 Professional, you need ten licenses for Windows 7 Professional to be in compliance with the terms of your software license. If, in addition, the virtual host machine is running Windows 7 Professional, you also need a license for the host.

Windows Server Titles and Virtual Machines

Several of the "more capable" Windows Server editions (Datacenter, Enterprise, and Standard) provide licenses to guest virtual machines that run the same (or earlier, depending on your downgrade rights) versions and editions of Windows Server. The details of the rights granted vary with edition and version. Example: With a host licensed for Windows Server 2016 Datacenter, you are entitled to run an unlimited number of virtual machines running Windows Server 2016 Datacenter, Standard, or Enterprise 2012, 2008 R2, 2008, and so on. Windows Server 2016 Standard grants licenses to run two additional virtual machines running Windows Server, but each additional two virtual machine guests require that you re-license all cores of the host machine.

There are a few subtle points in the licensing rules involving virtual hosts and guests:

  • All Windows Server licenses are considered to be assigned to the VM host.
  • A VM host running a hypervisor is also considered to consume a Windows Server license.
  • To run more virtual machines (under, say, Windows Server Standard) you must assign (or have available) more licenses to the VM host.
  • All Windows Server licenses must be evaluated using a single license rule, usually that of the most recent version of the most capable Windows Server edition.

The License Analytics evaluation process uses these rules to report on compliance, and also reports on what rules it used to do the evaluation.

The "less capable" editions in the Windows Server family (Essentials, Foundation, Web Edition, and so on) may either provide no rights for running additional copies in virtual machines, or (like Windows Server Web Edition) require a separate license for every copy running on either a physical or virtual machine.

SQL Server Titles and Virtual Machines

All SQL Server Enterprise and Datacenter licenses must be assigned to a physical server. Other edition licenses may also be assigned to virtual machine guests. License Analytics compares those license entitlements with the license requirements for a single physical machine. The license requirements for a single physical machine are the sum of any installation of SQL Server on the physical host environment combined with license requirements for all running virtual machine guests.

For the purposes of License Analytics, SQL Server licenses fall into these classes:

  • Enterprise and Datacenter editions can grant license rights to virtual machine guests when all physical host resources are licensed. All such licenses must be assigned to the physical host. The specific license rights vary by version and edition.
  • Other editions require a separate license for every physical and virtual environment running a copy of SQL Server. These licenses must be assigned to the physical or virtual machine running SQL Server.

License Analytics performs its calculations for VM environments based on rules derived from these classes. For complete information, see the Microsoft website.

Windows Server and SQL Server Titles and Physical Hardware

Cherwell Asset Management virtual environment discovery and inventory processes (and SCCM inventories imported by the CAM External Connector) report on certain hardware characteristics of virtual machine hosts and other machines it inventories, including the number of cores and processors installed. This is required to analyze certain SQL Server and Windows Server installations.

Newer and "more capable" titles are usually licensed for a particular number of hardware cores or processors.

The "less capable" SQL Server and Windows Server titles are generally licensed on a "one license per server" model, rather than on the number of physical cores or processors. These members of the SQL Server and Windows Server families usually do not host virtual machines.