Cannot add an ESX/ESXi host with running virtual machines to an EVC enabled Cluster

Products

• VMware vSphere ESXi

Issue/Introduction

Symptoms:

• Cannot add ESX/ESXi host with running virtual machines to an EVC enabled Cluster.
• If you try to add an ESX/ESXi host with running virtual machines to an EVC enabled Cluster, a message appears indicating that the host is in maintenance mode.

Environment

VMware ESXi 3.5.x Embedded
VMware vSphere ESXi 5.0
VMware ESXi 4.0.x Embedded
VMware ESXi 4.0.x Installable
VMware ESX Server 3.5.x
VMware vSphere ESXi 5.1
VMware ESX 4.1.x
VMware ESXi 4.1.x Embedded
VMware ESX 4.0.x
VMware ESXi 3.5.x Installable
VMware ESXi 4.1.x Installable

Resolution

An EVC enabled Cluster cannot determine the CPU Compatibility features used by any of the running virtual machines. A host has to be put in maintenance mode before it can be added to the EVC cluster.

To place the ESX host into maintenance mode:

1. vMotion the running virtual machines from the standalone host to the hosts already in the cluster.
2. When all of the machines are finished migrating, place the ESX host into maintenance mode.
3. Add the host to the cluster.

OR

1. Power down all of the running virtual machines on the ESX host.
2. Place the host into maintenance mode.
3. Add the host to the cluster.

If vCenter Server is a virtual machine:

1. Power down virtual machines on host B.
2. Add host B to EVC Cluster.
3. Perform one of these options:
   • Power down the vCenter Server virtual machine on host A.
     
     Or
     
     
   • Unregister the vCenter Server virtual machine using the vSphere Client connection directly to host A.
     
     
4. Connect to host B via vSphere Client, register the vCenter virtual machine and power on.
5. Power down all remaining virtual machines on host A and add to EVC Cluster.

For detailed instructions on completing the above steps, see the Basic System Administration Guide.

Note: It may also be possible to enable EVC on an existing cluster. For further details on the prerequisites and steps to enable EVC, see the Basic System Administration Guide.

Additional Information

For more information on EVC clusters, see Enhanced VMotion Compatibility (EVC) processor support (1003212).

Re-adding an ESX host to an EVC cluster
How to enable EVC in vCenter Server