Configure EVC to ensure that virtual machine migrations between hosts in the cluster do not fail because of CPU feature incompatibilities.
Several EVC approaches are available to ensure CPU compatibility:
- If all the hosts in a cluster are compatible with a newer EVC mode, you can change the EVC mode of an existing EVC cluster.
- You can enable EVC for a cluster that does not have EVC enabled.
- You can raise the EVC mode to expose more CPU features.
- You can lower the EVC mode to hide CPU features and increase compatibility.
Prerequisites
- Verify that all hosts in the cluster have supported CPUs for the EVC mode you want to enable. See http://kb.vmware.com/kb/1003212 for a list of supported CPUs.
- Verify that all hosts in the cluster are connected and registered on vCenter Server. The cluster cannot contain a disconnected host.
- Virtual machines must be in the following power states, depending on whether you raise or lower the EVC mode.
EVC Mode Virtual Machine Power Action Raise the EVC mode to a CPU baseline with more features. Running virtual machines can remain powered on. New EVC mode features are not available to the virtual machines until they are powered off and powered back on again. A full power cycling is required. Rebooting the guest operating system or suspending and resuming the virtual machine is not sufficient. Lower the EVC mode to a CPU baseline with fewer features. Power off virtual machines if they are powered on and running at a higher EVC Mode than the one you intend to enable. To verify the EVC mode for virtual machines, see Determine the EVC Mode of a Virtual Machine.
