Exceed the 4 vCPU limit for VM’s

How to exceed the 4 vCPU limit for VM’s on Hyper-V

Many times I was asked for the way to exceed the limitation of 4 virtual processors assigned to a virtual machine for Windows Server 2008 R2.

I guess there is still many Windows Server 2008 R2. hypervisor running on a physical server which has much more cores in your data-center.

Although It is very limiting, but I will not recommend you to modify VM’s setting on a productions servers to exceed the limit.

I will show you the steps, you can try it on your responsibility

Let’s start:
1- Copy the virtual machine configurations file, it’s a .xml file stored in the virtual machine folder.


2- Edit the copied configurations file with a text editor(Notepad)

Search for “processors” section. Then change the ‘count’ parameter
Note: ‘count’ number cannot exceed the number of cores of the host machine.
In this example I changed count from 4 to 8
Then save the file, pay special attention to save it in xml format

  
3- overwrite the original configurations file, check the VM’s state and make sure is off before overwriting the configurations file.
4- check the Number of logical processors from the VM settings, it should match the entered value in configuration file.