Hyper-V: The number of logical processors in use must not exceed the supported maximum

Applies To: Windows Server 2008 R2, Windows Server 2012

This topic is intended to address a specific issue identified by a Best Practices Analyzer scan. You should apply the information in this topic only to computers that have had the Hyper-V Best Practices Analyzer run against them and are experiencing the issue addressed by this topic. For more information about best practices and scans, see Best Practices Analyzer.

Operating System

Windows Server 2012 or Windows Server 2008 R2

Product/Feature

Hyper-V

Severity

Error

Category

Policy

Issue

The server is configured with too many logical processors.

Impact

Microsoft does not support running Hyper-V on this computer.

Resolution

Remove some processors from this machine or use msconfig to limit the number of available processors.

For information about removing processors, consult the documentation that came with the computer or contact the hardware manufacturer. For information about using the System Configuration utility (Msconfig.exe), see the following procedure.

You must be logged on as an administrator or a member of the Administrators group in order to complete this procedure.

To limit the number of available processors

  1. Open the System Configuration utility (Msconfig.exe). To do this, click Start, click Run, type msconfig, and then click OK.

  2. From the Boot tab, click Advanced options.

  3. Select Number of processors and then select a number in the list. Click OK.

  4. Restart the computer to run it using the new number of processors.

Additional references

For more information about supported configurations of Hyper-V and virtual machines running with Hyper-V, see Requirements and Limits for Virtual Machines and Hyper-V in Windows Server 2008 R2 (https://go.microsoft.com/fwlink/?LinkId=180919).