Should EVC be enabled?

Should EVC be enabled?

By doing so, EVC ensures that all virtual machines in the cluster are running on the same CPU instructions allowing for virtual machines to be live migrated (vMotion) between the ESXi hosts. When EVC is enabled on the cluster, all ESXi hosts in the cluster must adhere to that setting.

Can I disable EVC?

Click the Manage tab and click Settings. Select VMware EVC and click Edit. Select whether to enable or disable EVC. The EVC feature is disabled.

When should I use EVC mode?

The whole purpose of VMware EVC Mode is to allow the ability to be able to migrate virtual machines between ESXi hosts in the same cluster that are running dissimilar processors architectures.

Does EVC mode affect performance?

Generally the consensus is that setting the EVC mode on a cluster is a good thing to make it easier to admit future ESXi hosts and it doesn’t cause any performance degradation. After all, even with it set, it doesn’t prevent you from using the latest clock frequencies, deeper core counts, etc.

What technology allows vMotion between hosts utilizing different models?

VMware VMotion technology allows users to migrate running virtual machines between compatible physical servers with zero downtime.

What is the purpose of using enhanced vMotion compatibility EVC mode?

You can use the Enhanced vMotion Compatibility (EVC) feature to help ensure vMotion compatibility for the hosts in a cluster. EVC ensures that all hosts in a cluster present the same CPU feature set to virtual machines, even if the actual CPUs on the hosts differ.

How do I turn on EVC mode?


  1. Select a cluster in the vSphere inventory.
  2. Power off all the virtual machines on the hosts with feature sets greater than the EVC mode.
  3. Click the Configure tab, select VMware EVC, and click Edit.
  4. Enable EVC for the CPU vendor and feature set appropriate for the hosts in the cluster, and click OK.

How do I enable enhanced vMotion compatibility?

How is EVC used to improve CPU compatibility?

Using EVC prevents migrations with vMotion from failing because of incompatible CPUs. [Read more] 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.

How does EVC allow for uniform vMotion compatibility?

The way EVC allows for uniform vMotion compatibility, is by enforcing a CPUID (instruction) baseline for the virtual machines running on the ESXi hosts. That means EVC will allow and expose CPU instruction-sets to the virtual machines depending on the chosen and supported compatibility level.

Can a VM be configured in per-EVC mode?

When the cluster EVC mode is enabled, the script will show the used baseline. It also shows the VM hardware version because per-EVC is only available for VM hardware version 14 and up. If a virtual machine is configured with per-VM EVC, the baseline could differ from the cluster EVC configuration.

How to determine if a host is compatible with an EVC cluster?

By determining the EVC modes that the host can support, you can determine whether the host is compatible with other hosts in an EVC cluster. For hosts to be included in the same EVC cluster, all the hosts must support at least one common mode. [Read more]