Migrating a virtual machine in vSphere 5.x fails with the error: The operation is not allowed in the current connection state of the host

Migrating a virtual machine in vSphere 5.x fails with the error: The operation is not allowed in the current connection state of the host

Symptoms

• Cannot migrate a virtual machine in a vSphere 5.x environment.
• Migrating a virtual machine fails with the error:
  
  Relocate virtual machine
  The operation is not allowed in the current connection state of the host
  Time: xx/xx/xxxx xx:xx:xx
  Target: xxxxx
  vCenter Server: xxxxx
• The Summary tab of the powered on virtual machine reports this information:
  
  
  • CPU Usage - 0 MHz
• • Memory Usage - 0.00 MB

Resolution

To resolve this issue, perform these steps, verifying if the issue is resolved after each step:

1. Restart the VMware VirtualCenter Server Service.
2. Restart the Management agents on the ESX host running the virtual machine. For more information, see Restarting the Management agents on an ESXi or ESX host (1003490).
3. Disconnect and reconnect the ESX host that is running the virtual machine to force vCenter Server to retrieve an updated set of data relating to the objects registered to the host.