Virtualizing SQL Server on vSphere – Licensing

by Barnaby Jeans

In a previous article, we talked about some best practices for virtualizing Microsoft SQL Server on vSphere and to follow it up I want to take some time to answer a common question – what is the licensing impact when virtualizing SQL server.

I have just completed a 3 week, 5 city, tour across Canada talking to companies about virtualizing Business Critical Applications (SQL Server, Exchange, SharePoint, Oracle, SAP) on vSphere.  One of the most frequent questions has to do with how to license SQL Server and understanding the Microsoft licensing cost implications as they consolidate their physical environments to virtual.  During those conversation they quickly come to appreciate that in many cases their existing licenses cover them for more virtual machines than they had planned to deploy.

As Microsoft offers a number of different licensing options for its software, you should consult with your Microsoft representative to obtain the most accurate licensing information for your situation.

Below I’ve provided a summary based on the available documentation to help you understand your options when it comes to running SQL Server on vSphere.

SQL Server 2008 R2

From the SQL Server 2008R2 Licensing Quick Reference Guide

Licensing for Virtualization Under the Per Processor Model
The number of operating system environments (OSEs) in which you may run instances of SQL Server 2008 R2 under the Per Processor model depends upon the edition you license and whether or not you license all of the physical processors with a Per Processor License.

Licensing All Physical Processors If you license all of the physical processors on the server (one license per physical processor), you may run unlimited instances of the SQL Server software in the following number of OSEs (either physical or virtual):

Edition	# of OSEs in Which You May Run SQL Server
SQL Server 2008 R2 Datacenter	Unlimited
SQL Server 2008 R2 Enterprise	Up to 4 per license

SQL Server 2012

With the release of SQL 2012 Microsoft has changed the licensing and has retired the Datacenter Edition as well as moved to Core-Based licensing.

From the SQL Server 2012 Licensing Quick Reference Guide (March 2012)

SQL Server 2012 offers expanded virtualization rights, options and benefits to provide greater flexibility for customers deploying in virtual environments. When deploying SQL Server 2012 software in virtualized environments, customers have the choice to license either individual virtual machines (VMs) as needed, or to license for maximum virtualization in highly virtualized, private cloud, or dynamic environments. Maximum virtualization can be achieved by licensing the entire physical server with Enterprise Edition core licenses and covering those licenses with Software Assurance.

In looking at the information above, you’ll note that SQL Server 2008 R2 Enterprise Edition already provides you with the ability to run 4 virtual machines with an existing license, and in most cases, customers are able to consolidate multiple physical SQL Server environments down to a much smaller number of physical hosts running SQL Server in vSphere.

Additionally, both SQL Server 2008 R2 Datacenter Edition and SQL Server 2012 Enterprise Edition with SA provide you the ability to run as many VMs on a physical host as the hardware allows.  This makes it very easy to include SQL Server in your Private Cloud initiatives.

The last documents that you’ll want to be familiar with are the Microsoft Application Server License Mobility brief and Licensing Microsoft Server Products in Virtual Environments.  Together the documents mentioned above provide a good summary of your options.  Once I walk customers through some of the information in these documents, they realize that in addition to making sense technically and operationally, it can also lead to reduced SQL Server license costs as they virtualize SQL Sever on vSphere.

As always, we suggest you consult with your Microsoft representative to obtain the most accurate licensing information for your situation.