| Feature | Cluster-based EVC | Per-VM EVC |
|---|---|---|
| Scope of setting | Applies to an entire host cluster. All hosts present the same CPU feature baseline. | Applies to an individual virtual machine. The EVC mode becomes an attribute saved with the VM. |
| Configuration point | Configured at the cluster level in vCenter. | Configured per virtual machine, requires VM to be powered off. |
| Inheritance behavior | VMs inherit the cluster’s EVC mode when powered on. | Overrides cluster EVC; VM keeps its own EVC mode even when migrating across clusters. |
| Mobility across clusters | Only works if destination cluster supports a compatible EVC baseline; EVC does not travel with the VM. | VM “carries” its EVC baseline with it, helping with cross-cluster or cross-site migration. |
| Effect of power cycles | If VM moves out of the cluster, its EVC mode resets based on the new environment’s EVC/host baseline. | Power cycles don’t reset the per-VM EVC; the VM retains compatibility settings. |
| Flexibility | Less granular; changing cluster EVC can require operations (host requirements, power states). | More flexible for mixed environments or migrations outside original cluster. |
| Requirements | Works with supported hosts in the cluster. | Needs supported VM hardware version (e.g., hardware version 14+ in practice). |
Key Pointers:
- Cluster-based EVC ensures uniform CPU features across all hosts in a cluster so that VMs can migrate (vMotion) between hosts without CPU incompatibilities.
- Per-VM EVC makes the EVC compatibility a property of the VM, enabling it to retain compatibility settings across migrations and clusters, and not just depend on the host cluster configuration.