VM not migrated while HV put in maintenance

Issue

• Switching a hypervisor into maintenance will leave a virtual machine in ?-state
• Unable to put hypervisor into maintenance, due to issues on migrating a virtual machine
• Unable to migrate a virtual machine, while a hypervisor was put into maintenance. Even by running vdsClient shutdown nor vdsClient destroy did not shutdown the VM. It needs to be killed the process by kill -9
• A virtual machine process needs to be killed by kill -9 to be able to switch Hypervisor into maintenance