Enabling and managing EVC on ESXi clusters in vCenter Server 5.x and 6.0

Products

VMware vCenter Server

Issue/Introduction

This article provides methods to enable and manage an Enhanced vMotion Compatibility (EVC) cluster in vCenter Server 5.x and 6.0.

Environment

VMware vCenter Server 5.0.x
VMware vCenter Server 5.1.x
VMware vCenter Server 5.5.x
VMware vCenter Server 6.0.x

Resolution

Note: This process may require downtime when changing EVC baseline levels or establishing an EVC baseline for the first time. Depending on the operation to be performed, you may have to power off the virtual machines before making changes to the EVC baseline to update the instruction sets visible to the virtual machines.

You are enabling EVC on a cluster for the first time:

Verify the enhanced motion compatibility and CPU compatibility for your processor(s) to determine the EVC level that the cluster will support. For more information, see EVC and CPU Compatibility FAQ (1005764) and Enhanced vMotion Compatibility (EVC) processor support (1003212).

When enabling EVC for a cluster with Intel processors of the Xeon E3 or Xeon E5 family that have different revision numbers (v2, v3, v4), an EVC baseline is required. This is due to new instruction sets being available in the different revisions. Though the processors have the same EVC baseline, the processors must present the same instruction sets to all the virtual machines.
As with Xeon processors with different revisions, when enabling EVC for a cluster with Intel processors of the same Xeon family (e.g. E56xx, X56xx, L56xx), an EVC baseline is required. This is due to new instruction sets being available in the different revisions. Though the processors have the same EVC baseline, the processors must present the same instruction sets to all the virtual machines.

If enabling EVC on an existing cluster, which has running virtual machines, you may require to power off the virtual machines. For more information, see Enable EVC on an Existing Cluster section of the vCenter Server and Host Management guide.
To enable EVC on the cluster, where vCenter Server is running, see Enabling EVC on a cluster when vCenter Server is running in a virtual machine (1013111).

You can manage existing EVC baslines in an ESXi host cluster in the following ways:

Note: If you are attempting to add an ESXi host to the an EVC enabled cluster with running virtual machines, see Cannot add an ESX/ESXi host with running virtual machines to an EVC enabled Cluster (1009571).

Add a new ESXi host with an older CPU than the current EVC baseline. For more information, see Adding a new ESXi host with an older CPU than the current EVC baseline (2127208).
Add a new ESXi host with a newer CPU than the current EVC baseline.

The ESXi host can be added to the cluster if the ESXi host is new to the environment and currently does not have virtual machines running on it. The host will need to be placed into maintenance mode prior to adding.
If the ESXi host has virtual machines running and\or is part of an existing EVC baseline, any running virtual machines will need to be powered off and the host placed into maintenance mode prior to adding.

Add an ESXi host with a similar CPU to the current EVC baseline. For more information, see Adding an ESXi host with a similar CPU to the current EVC baseline (2127212).
Removing ESXi host from an existing cluster.

When removing an ESXi host from an existing cluster, the EVC baseline will remain on the running virtual machines until their are powered off and back on.

Note: To troubleshoot issues that you may experience while managing the EVC baselines, see Cannot add an ESX/ESXi host with running virtual machines to an EVC enabled Cluster (1009571).

Performing vMotion for virtual machines between two clusters must take the following information into account when configuring EVC baseline:

vMotioning virtual machines between two clusters should take the following information into account when configuring EVC baselines. If you are looking to continually vMotion virtual machines between two ESXi clusters, ensure that the source and destination clusters have either identical CPUs for all ESXi hosts being used or identical EVC base lines configured for both clusters.

vMotion to a cluster with new CPUs or EVC Base Line

Hot Migration (vMotion) and Cold Migration both viable options

If you are going from an cluster with a older CPU or lower EVC baseline to a cluster with newer CPUs or higher EVC baseline, the virtual machine will relocate successfully through vMotion. This is due to the instruction sets presented from the older CPUs in the source cluster still being presented with the newer CPUs in the destination cluster. The virtual machine needs to be power cycled at a later date to pick up all of the newest instruction sets, but this will not prevent the vMotion operations.

vMotion to a cluster with older CPUs or EVC Base Line

Cold Migration only viable option

If you are migrating from a cluster with a newer CPU or higher EVC baseline to a cluster with older CPUs or lower EVC baseline, the virtual machine must be powered off. vMotion is not supported for virtual machines to be relocated from an ESXi host with a newer CPU to an ESXi host with an older CPU. This is due to the instruction sets presented from the newer CPUs in the source cluster not being present from on the older CPUs in the destination cluster.
vMotion to a cluster with CPUs from a different manufacturer:

vMotion is only supported between CPUs of the same manufacture. All ESXi hosts in a cluster should be either Intel or AMD.
For changing the the EVC Mode for a cluster, see the Change the EVC Mode for a Cluster section of vCenter Server and Host Management guide.

Additional Information

Enhanced vMotion Compatibility (EVC) processor support
EVC and CPU Compatibility FAQ
Cannot add an ESX/ESXi host with running virtual machines to an EVC enabled Cluster
How to enable EVC in vCenter Server
Adding an ESXi host with an older CPU than the current EVC baseline
Adding a VMware ESXi host to a VMware ESXi cluster with a CPU similar to Enhanced vMotion Compatibility baseline
vCenter Server 5.x および 6.0 の ESXi クラスタ上の EVC の有効化と管理
在 vCenter Server 5.x 和 6.0 中启用和管理 ESXi 群集上的 EVC