To improve CPU compatibility between hosts that have varying CPU feature sets, you can hide some host CPU features from the virtual machines by placing the host in an Enhanced vMotion Compatibility (EVC) cluster. Hosts in an EVC cluster and hosts that you add to an existing EVC cluster must meet EVC requirements.

  • Power off all virtual machines in the cluster that are running on hosts with a feature set greater than the EVC mode that you intend to enable. You can also migrate these virtual machines out of the cluster.
  • All hosts in the cluster must meet the following requirements:
Requirements Description
Supported ESXi version ESXi 5.5 or later.
vCenter Server The host must be connected to a vCenter Server system.
CPUs A single vendor, either AMD or Intel.
Advanced CPU features enabled Enable these CPU features in the BIOS if they are available:
  • Hardware virtualization support (AMD-V or Intel VT)
  • AMD No eXecute(NX)
  • Intel eXecute Disable (XD)
Note: Hardware vendors sometimes disable particular CPU features in the BIOS by default. You might have problems enabling EVC because the EVC compatibility checks detect the absence of features that are expected to be present for a particular CPU. If you cannot enable EVC on a system with a compatible processor, ensure that all features are enabled in the BIOS.
Supported CPUs for the EVC mode that you want to enable To check EVC support for a specific processor or server model, see the VMware Compatibility Guide at http://www.vmware.com/resources/compatibility/search.php.
Configured for vMotion See Host Configuration for vMotion.