Microsoft SQL Server, Processor Licensing, and Virtual Servers

Use terms of Microsoft server products can be complex and difficult to interpret.  Microsoft SQL Server licensing rules for use in virtual environments demonstrate that a careful review of the use terms is necessary to avoiding copyright or contract violations.

The current licensing rules for Microsoft SQL Server Enterprise provide that when licensed under a per-processor licensing structure, the licensee may install and run an unlimited number of instances of SQL Server Enterprise in a virtual environment as long as each physical processor in the computer is assigned a processor license. If a server has two processors, for example, assignment of one unique processor license to each processor allows the licensee to run an unlimited number of virtual SQL Server installations. This licensing feature of SQL Server Enterprise is particularly useful for businesses that need multiple installations of SQL Server and have computers with the processing power to support multiple virtual operating systems each with an installation of SQL Server. Additionally, the pricing structure of SQL Server Enterprise under a processor license may provide a business with more value if enough virtual installations are used on one multiple-processor server.

The processor-based licensing rules for SQL Server Standard, however, do not permit the licensee to operate an unlimited number of SQL Server installations in virtual operating systems. A SQL Server Standard processor license is required for each physical or virtual processor on which an installation of SQL Server operates.  Purchasing SQL Server standard under a processor licensing structure may be a less advantageous decision for businesses that want to license SQL Server on a per-processor basis but also anticipate running multiple SQL Server installations in virtual environments.

If you have questions regarding Microsoft SQL Server licensing or are considering purchasing SQL Server for your environment, you should consult counsel and professionals with the experience to help you interpret Microsoft licensing rules and select the right product for your business.