Description of problem:
VM import from RHV of a Fedora 32 VM with OS type RHEL8, to target "standard" storage class.
While the VM's disk was copied, VM import of the same VM, to target NFS storage class.

Result:
The first VM import was displayed in UI as if it was stuck @85%.
The second VM import failed:
At first it failed on disk being locked, and then, after few minutes, it got this other failure: 
"
The virtual machine could not be imported.
DataVolumeCreationFailed: Data volume default/fedora32-nfs-b870c429-11e0-4630-b3df-21da551a48c0 creation failed: Internal error occurred: failed calling webhook "datavolume-mutate.cdi.kubevirt.io": Post https://cdi-api.openshift-cnv.svc:443/datavolume-mutate?timeout=30s: no endpoints available for service "cdi-api"
"

Piotr Kliczewski:

I checked your environment and found one importer pod (importer-fedora32-1-b870c429-11e0-4630-b3df-21da551a48c0) in Terminating status:

I see a message there: 
        message: 'Unable to connect to imageio data source: Fault reason is "Operation
          Failed". Fault detail is "[Cannot transfer Virtual Disk: The following disks
          are locked: GlanceDisk-f6c31e5. Please try again in a few minutes.]". HTTP
          response code is "409". HTTP response message is "409 Conflict".'

I suspect it failed due to the same disk being imported already.

The DV (fedora32-1-b870c429-11e0-4630-b3df-21da551a48c0) is still in:

  phase: ImportInProgress
  progress: 100.00%

Corresponding VMImport contains a message:
  kind: VirtualMachineImport
  metadata:
    annotations:
      vmimport.v2v.kubevirt.io/progress: "85"
      vmimport.v2v.kubevirt.io/source-vm-initial-state: down
    name: vm-import-fedora32-1-xfhww
....
  dataVolumes:
  - name: fedora32-1-b870c429-11e0-4630-b3df-21da551a48c0


Interesting point is that the second import failed to create DV.

  kind: VirtualMachineImport
  name: vm-import-fedora32-nfs-p22xd
...
      message: 'Data volume default/fedora32-nfs-b870c429-11e0-4630-b3df-21da551a48c0
        creation failed: Internal error occurred: failed calling webhook "datavolume-mutate.cdi.kubevirt.io":
        Post https://cdi-api.openshift-cnv.svc:443/datavolume-mutate?timeout=30s:
        no endpoints available for service "cdi-api"'
      reason: DataVolumeCreationFailed


Further steps on this same environment:
VM import a RHEL-7 VM, from RHV to CNV, using default storage, which is standard (default) - kubernetes.io/cinder.
The VM import seemed stuck in UI on 10% progress.
In UI there was NO indication of why it is not progressing.

There were errors in the vm-import-controller log like: "ovirt client panicked: runtime error: invalid memory address or nil pointer dereference" 

I then tried to import another RHEL-7 VM to NFS storage. That VM import finished successfully.
I then deleted this VM, and tried to VM import it again to NFS storage - That failed with import error, related to ovirt.
I think the error was something like: "invalid memory address or nil pointer dereference" in UI.

I removed this VM import resource, and tried again to run VM import from RHV, but that gets stuck on 
"Checking RHV API credentials" stage forever.
That is, it is no longer possible to do VM import from RHV.

Checking VM import from VMware provider, that worked before the above steps:
For existing/new VMware provider,
It is "stuck" in "Checking vCenter credentials" stage.

Version-Release number of selected component (if applicable):
CNV-2.4 from July 9 2020.


Additional info:
standard (default) kubernetes.io/cinder:
This comes by default with OCP4.4+,
It should provision columns on top of OpenStack Platform (RHOSP) Cinder.
In our case it is not functional because it requires configuration with openstack which we don't do at the moment.