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5.5. Hot Plugging vCPUs

You can hot plug vCPUs. Hot plugging means enabling or disabling devices while a virtual machine is running.

Important

Hot unplugging a vCPU is only supported if the vCPU was previously hot plugged. A virtual machine’s vCPUs cannot be hot unplugged to less vCPUs than it was originally created with.

The following prerequisites apply:

  • The virtual machine’s Operating System must be explicitly set in the New Virtual Machine or Edit Virtual Machine window.
  • The virtual machine’s operating system must support CPU hot plug. See the table below for support details.
  • Windows virtual machines must have the guest agents installed. See Section 3.3.2, “Installing the Guest Agents and Drivers on Windows”.

Hot Plugging vCPUs

  1. Click ComputeVirtual Machines and select a running virtual machine.
  2. Click Edit.
  3. Click the System tab.
  4. Change the value of Virtual Sockets as required.
  5. Click OK.

Table 5.1. Operating System Support Matrix for vCPU Hot Plug

Operating SystemVersionArchitectureHot Plug SupportedHot Unplug Supported

Red Hat Enterprise Linux Atomic Host 7

 

x86

Yes

Yes

Red Hat Enterprise Linux 6.3+

 

x86

Yes

Yes

Red Hat Enterprise Linux 7.0+

 

x86

Yes

Yes

Red Hat Enterprise Linux 7.3+

 

PPC64

Yes

Yes

Microsoft Windows Server 2008

All

x86

No

No

Microsoft Windows Server 2008

Standard, Enterprise

x64

No

No

Microsoft Windows Server 2008

Datacenter

x64

Yes

No

Microsoft Windows Server 2008 R2

All

x86

No

No

Microsoft Windows Server 2008 R2

Standard, Enterprise

x64

No

No

Microsoft Windows Server 2008 R2

Datacenter

x64

Yes

No

Microsoft Windows Server 2012

All

x64

Yes

No

Microsoft Windows Server 2012 R2

All

x64

Yes

No

Microsoft Windows Server 2016

Standard, Datacenter

x64

Yes

No

Microsoft Windows 7

All

x86

No

No

Microsoft Windows 7

Starter, Home, Home Premium, Professional

x64

No

No

Microsoft Windows 7

Enterprise, Ultimate

x64

Yes

No

Microsoft Windows 8.x

All

x86

Yes

No

Microsoft Windows 8.x

All

x64

Yes

No

Microsoft Windows 10

All

x86

Yes

No

Microsoft Windows 10

All

x64

Yes

No