The CPU hot plug option lets you add CPU resources for a virtual machine while the machine is powered on.

The following conditions apply:

  • For best results, use virtual machines with hardware version 8 or later.
  • Hot-adding multicore virtual CPUs is supported only with hardware version 8 or later.
  • Not all guest operating systems support CPU hot add. You can disable these settings if the guest is not supported.
  • To use the CPU hot-add feature with hardware version 7 virtual machines, set Number of cores per socket to 1.
  • Adding CPU resources to a running virtual machine with CPU hot plug enabled disconnects and reconnects all USB passthrough devices connected to that virtual machine.


Verify that the virtual machine is running under the following conditions:

  • VMware Tools is installed. This condition is required for hot plug functionality with Linux guest operating systems.
  • The virtual machine has a guest operating system that supports CPU hot plug.
  • The virtual machine is using hardware version 7 or later.
  • The virtual machine is powered off.
  • Required privileges: Virtual Machine.Configuration.Settings on the virtual machine


  1. In the vSphere Client inventory, right-click the virtual machine and select Edit Settings.
  2. Click the Options tab and under Advanced, select Memory/CPU Hotplug.
  3. Change the CPU Hot Plug setting.
  4. Click OK to save your changes.

What to do next

You can now add CPUs to the powered on virtual machine.