Bug 1408823

+++ This bug is a downstream clone. The original bug is: +++
+++   bug 1396153 +++
======================================================================

Description of problem:

As reported from the customer:

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After we import a VM from KVM we have certain operations we need to complete... including setting the Instance Type, Optimizing for Server and picking it's network... However through the API when we attempt to alter the instance type we get an error from RHVM.

This will impact our migration of close to 800 VMs over the coming months.

---

    vms_service = connection.system_service().vms_service()

    vm = vms_service.list(search='name=' + vm_name)
    if len(vm) != 1:
        print 'not found, or duplicate'
        exit()

    vm = vm[0]

    it_service = connection.system_service().instance_types_service().list()
    vm_instance_type_obj = None
    for it in it_service:
        if it.name == vm_instance_type:
            vm_instance_type_obj = it
            break
    if vm_instance_type_obj == None:
        print 'could not find instant type'
        exit()

    # GET OUR VM
    vm_service = vms_service.vm_service(vm.id)

    # UPDATE OUR VM
    vm_service.update(
        types.Vm(
            instance_type=vm_instance_type_obj
        )
    )

Traceback (most recent call last):
  File "/usr/local/lib/python2.7/site-packages/fabric/main.py", line 743, in main
    *args, **kwargs
  File "/usr/local/lib/python2.7/site-packages/fabric/tasks.py", line 427, in execute
    results['<local-only>'] = task.run(*args, **new_kwargs)
  File "/usr/local/lib/python2.7/site-packages/fabric/tasks.py", line 174, in run
    return self.wrapped(*args, **kwargs)
  File "/Users/ccrawford40/git/capella/uops-systems-code/fabric/builds/rhev_ops.py", line 103, in rhev_dr_import_config
    instance_type=vm_instance_type_obj
  File "/usr/local/lib/python2.7/site-packages/ovirtsdk4/services.py", line 24130, in update
    self._check_fault(response)
  File "/usr/local/lib/python2.7/site-packages/ovirtsdk4/service.py", line 98, in _check_fault
    Service._raise_error(response, fault)
  File "/usr/local/lib/python2.7/site-packages/ovirtsdk4/service.py", line 71, in _raise_error
    raise Error(msg)
ovirtsdk4.Error: Fault reason is "Operation Failed". Fault detail is "[Cannot edit VM. Cannot set single display device via VNC display.]". HTTP response code is 400.

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If the customer first modifies the console from CIRRUS to QXL, the above code snippet works without issues. Similarly, if they perform the following via the SDK, this also works without issue:

------8<-----------
 
  vm_service.update(
        types.Vm(
            display=types.Display(
            single_qxl_pci=False
            )
        )
    )

    vm_service.update(
        types.Vm(
            instance_type=vm_instance_type_obj
        )
    )

------8<-----------


Version-Release number of selected component (if applicable):
rhevm-4.0.4.4-0.1

How reproducible:
Always for customer

Steps to Reproduce:
1. Import a VM from KVM
2. Attempt to update the VM's instance type
3.

Actual results:

Unless the console type is set first (explicitly), then the above error is returned.

Expected results:

Instance type should be set without error.
Additional info:

(Originally by jhunsaker)