By default, you cannot add CPU resources to a virtual machine when the virtual machine is turned on. The CPU hot plug option lets you add CPU resources to a running virtual machine.
The following conditions apply:
- For best results, use virtual machines that are compatible with ESXi 5.0 or later.
- Hot-adding multicore virtual CPUs is supported only with virtual machines that are compatible with ESXi 5.0 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 plug feature with virtual machines that are compatible with ESXi 4.x and later, set the 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 that are connected to that virtual machine.
Prerequisites
Required privileges:
Verify that the virtual machine is running and is configured as follows.
- Latest version of VMware Tools installed.
- Guest operating system that supports CPU hot plug.
- Virtual machine compatibility is ESX/ESXi 4.x or later.
- Virtual machine is turned off.
Procedure
- Right-click a virtual machine in the inventory and select Edit Settings.
- On the Virtual Hardware tab, expand CPU, and select Enable CPU Hot Add.
- Click OK.