Cross the 4 Virtual Processors count limit under Windows Server 2008 R2 Hyper-V


I made a promise in my last blog to show you how to exceed the limit of 4 virtual processors assigned to a virtual machine with Windows Server 2008 R2 (SP1 too)

So, let’s start:

1- Go to the virtual machine configurations file, it’s a .xml file stored in the virtual machine folder and has the ID of the VM as a name.

Copy that file:


2- Paste the file wherever you want and edit it with a text editor (notepad)


3- Look for the “Processors” section. You will found the ‘count’ parameter

Image 4- Change the count value to the desired value : in this example i will change 2 by 8

Image5- now, save the file (be sure it’s always a xml file), then copy it and replace the original file. The virtual machine must be stopped before continuing.

6- It’s done, you can now go to the VM settings and enjoy the new value appearing into the number of virtual processors value under the CPU tab.


7- Start your virtual machine…. Make a look!!!

It’s great, works but not supported by Microsoft. Don’t forget that you cant’ type any value under the cpu count, look to my last blog for the virtual processors count conditions and limit.

Another great method to cross the 4 VP limit: Migrate to the excellent Windows Server 2012 Hyper-V

5 thoughts on “Cross the 4 Virtual Processors count limit under Windows Server 2008 R2 Hyper-V

  1. Yes, in fact, when you are in a highly available platform, the xml file is handled by the cluster service. To modify it this way, you have to shutdown the cluster service and the vmms service. Did you tried to copy the file to a location, modify it and then paste and rep^lace the original one

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s