Migrating a virtual machine from one host to another within a cluster fails with the error: Unable to create scheduler group for migration worlds

Products

• VMware vCenter Server

Issue/Introduction

Symptoms:

• Unable to migrate a virtual machine from one host to another within a cluster
• Migrating a virtual machine from one host to another within a cluster fails
• The vCenter Server Tasks and Events tab indicates that the migration failed
• You see the error:
  
  Unable to create scheduler group for migration worlds: Already exists
  
  
• vMotion stops at 10% for a very long time and then fails
  
• The vm-support -x command does not show the virtual machine as running on any of the hosts in the cluster
• Restarting management services of the hosts and the VirtualCenter Server service has no effect

Environment

VMware VirtualCenter 2.5.x
VMware vCenter Server 4.0.x

Resolution

This issue may occur if the virtual machine is registered on more than one ESX host in the cluster.

To ensure that the virtual machine is registered only on one of the ESX hosts in the cluster:

1. Run this command on all the hosts in the cluster to identify the hosts on which the virtual machine is registered:
   
   vmware-cmd -l
   
   
2. Run this command to unregister the virtual machine from the hosts on which it is registered:
   
   vmware-cmd -s unregister <path to vmx>
   
   Where <path to vmx> is the path of the.vmx file of the virtual machine.
   
   
3. Run this command to verify that the virtual machine is no longer registered on any of the hosts in the cluster:
   
   vmware-cmd -l
   
   
4. Run this command to register the virtual machine on one of the hosts in the cluster:
   
   vmware-cmd -s register <path to vmx>
   
   
5. Power on the virtual machine and test vMotion.