The current implementation is it deletes all disks of the VM, user can uncheck the checkbox and then delete the disks manually.
An improvement here can be listing the disks in the delete modal to let users choose what disks they want to delete along with the VM, as the bug suggested.

@gveitmic I think the issue here would be the same even if we create a list of disks

When someone selects cd-rom in the customization page, we create a different datavolumetemplate under the hood.
So the resulting VM would have two volumes.

Even if the ISO is shared across vms, the data volume creates the PVC from the source provided (the iso).
VMs that shares ISO do not actually share the same PVC. But those PVCs share the same source. 

So for this reason you see 2x

Even if we create a list, the user will uncheck the CD ROM disk thinking that he doesn't want to delete the ISO, but actually, that disk is a copy of the iso 
mad for that VM, so he probably wants to delete it. 


Maybe we are handling the CD-ROM thing in a non-expected way?

Hi Ugo,

Thanks for the explanation, but I'm a bit confused.

(In reply to Ugo Palatucci from comment #2)
> When someone selects cd-rom in the customization page, we create a different
> datavolumetemplate under the hood.
> So the resulting VM would have two volumes.

OK, if I attach the CD in the customisation page it does say 'Clone PVC'.
But I'm not using that because I don't want to clone anything, see from comment#0:

(In reply to Germano Veit Michel from comment #0)
...
> 6. Go to the Disks tab
> 7. Detach all Disks
> 8. Add a new Disk, a CD-ROM that is bootable for installing Guest
>    Source: Use an existing PVC       <--------
>    Type: CD-ROM
>    [x] Use this disk as a boot source
> 9. Click Save and add the CDROM
...

Is this actually the same thing in the backend? Its not right? I just never used that option as it says clone...

> Maybe we are handling the CD-ROM thing in a non-expected way?
I don't know, that 'Clone PVC' in the Customization page is actually weird.
Why would one want to duplicate ISOs? It's a read-only media, there is no need.

Let me explain in more detail what I do:
* Upload ISO via the console, in the create PVC dialog I upload a local ISO file form my computer
* On each VM I want to use it, I go to Disks -> Add -> Use an existing PVC and point it to the upload above.

Maybe I am overcomplicating things and doing it in a different way the system was developed for?

Anyway... see 2 VMs "sharing the same ISO" which should give you a better idea of the issue:

First Windows VM, just dataVolumeTemplates and volumes sections

$ oc --context admin-metal -n openshift-cnv get vm windows-1 -o yaml | yq e '.spec | (.dataVolumeTemplates,.template.spec.volumes)'
- metadata:
    creationTimestamp: null
    name: windows-1-osdisk
    namespace: openshift-cnv
    ownerReferences:
      - apiVersion: kubevirt.io/v1
        blockOwnerDeletion: false
        kind: VirtualMachine
        name: windows-1
        uid: c520ad07-d6a4-4e54-868e-13c9f24a95b7
  spec:
    preallocation: false
    source:
      blank: {}
    storage:
      resources:
        requests:
          storage: 60Gi
      storageClassName: synology

- dataVolume:
    name: windows-1-osdisk
  name: osdisk
- name: cdrom
  persistentVolumeClaim:
    claimName: windows10

Same for second Windows VM

$ oc --context admin-metal -n openshift-cnv get vm windows-2 -o yaml | yq e '.spec | (.dataVolumeTemplates,.template.spec.volumes)'
- metadata:
    creationTimestamp: null
    name: windows-2-osdisk
    namespace: openshift-cnv
    ownerReferences:
      - apiVersion: kubevirt.io/v1
        blockOwnerDeletion: false
        kind: VirtualMachine
        name: windows-2
        uid: 73524c56-b583-4fed-9ba6-4b562b11923b
  spec:
    preallocation: false
    source:
      blank: {}
    storage:
      resources:
        requests:
          storage: 60Gi
      storageClassName: synology
- name: cdrom
  persistentVolumeClaim:
    claimName: windows10
- dataVolume:
    name: windows-2-osdisk
  name: osdisk

If I go to the delete dialog of any of them, it says Delete Disk (2x), so I assume osdisk and my shared ISO (which I want to keep).

I don't think I'm using DV for the ISO. Its a single PVC for both:

$ oc --context admin-metal -n openshift-cnv get pvc | grep windows
windows-1                   Bound    pvc-c90e059e-c782-490f-93fd-b96708c548b1   68174084064    RWX            synology            16m
windows-1-osdisk            Bound    pvc-7c7d3709-283f-45d6-ba5f-9bc420c3fb13   68174084064    RWX            synology            11m
windows-2-osdisk            Bound    pvc-dd85550b-190d-4e0c-bfae-20cd7251207f   68174084064    RWX            synology            9m34s
windows-2-windows-2         Bound    pvc-1b84abc5-2f08-4f4b-8613-64de2dcb6b04   68174084064    RWX            synology            12m
windows10                   Bound    pvc-6c5a4111-d559-4dcb-b227-80ce8ec97b95   13634816813    RWX            synology            13d   <--- this is the ISO

$ oc --context admin-metal -n openshift-cnv get pvc windows10 -o yaml
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  annotations:
    cdi.kubevirt.io/storage.bind.immediate.requested: "true"
    cdi.kubevirt.io/storage.condition.bound: "true"
    cdi.kubevirt.io/storage.condition.bound.message: ""
    cdi.kubevirt.io/storage.condition.bound.reason: ""
    cdi.kubevirt.io/storage.condition.running: "false"
    cdi.kubevirt.io/storage.condition.running.message: Upload Complete
    cdi.kubevirt.io/storage.condition.running.reason: Completed
    cdi.kubevirt.io/storage.contentType: kubevirt
    cdi.kubevirt.io/storage.deleteAfterCompletion: "true"
    cdi.kubevirt.io/storage.pod.phase: Succeeded
    cdi.kubevirt.io/storage.pod.ready: "false"
    cdi.kubevirt.io/storage.pod.restarts: "0"
    cdi.kubevirt.io/storage.preallocation.requested: "false"
    cdi.kubevirt.io/storage.upload.target: ""
    cdi.kubevirt.io/storage.uploadPodName: cdi-upload-windows10
    pv.kubernetes.io/bind-completed: "yes"
    pv.kubernetes.io/bound-by-controller: "yes"
    volume.beta.kubernetes.io/storage-provisioner: cluster.local/nfs-subdir-external-provisioner
    volume.kubernetes.io/storage-provisioner: cluster.local/nfs-subdir-external-provisioner
  creationTimestamp: "2023-04-05T23:35:45Z"
  finalizers:
  - kubernetes.io/pvc-protection
  labels:
    alerts.k8s.io/KubePersistentVolumeFillingUp: disabled
    app: containerized-data-importer
    app.kubernetes.io/component: storage
    app.kubernetes.io/managed-by: cdi-controller
    app.kubernetes.io/part-of: hyperconverged-cluster
    app.kubernetes.io/version: 4.12.2
  name: windows10
  namespace: openshift-cnv
  resourceVersion: "102949"
  uid: 6c5a4111-d559-4dcb-b227-80ce8ec97b95
spec:
  accessModes:
  - ReadWriteMany
  resources:
    requests:
      storage: "13634816813"
  storageClassName: synology
  volumeMode: Filesystem
  volumeName: pvc-6c5a4111-d559-4dcb-b227-80ce8ec97b95
status:
  accessModes:
  - ReadWriteMany
  capacity:
    storage: "13634816813"
  phase: Bound

And here is the PV

$ oc --context admin-metal -n openshift-cnv get pv pvc-6c5a4111-d559-4dcb-b227-80ce8ec97b95 -o yaml
apiVersion: v1
kind: PersistentVolume
metadata:
  annotations:
    pv.kubernetes.io/provisioned-by: cluster.local/nfs-subdir-external-provisioner
  creationTimestamp: "2023-04-05T23:35:47Z"
  finalizers:
  - kubernetes.io/pv-protection
  name: pvc-6c5a4111-d559-4dcb-b227-80ce8ec97b95
  resourceVersion: "101064"
  uid: a375f313-605e-43f5-9494-57779a294657
spec:
  accessModes:
  - ReadWriteMany
  capacity:
    storage: "13634816813"
  claimRef:
    apiVersion: v1
    kind: PersistentVolumeClaim
    name: windows10
    namespace: openshift-cnv
    resourceVersion: "101056"
    uid: 6c5a4111-d559-4dcb-b227-80ce8ec97b95
  nfs:
    path: /volume4/openshift/openshift-cnv-windows10-pvc-6c5a4111-d559-4dcb-b227-80ce8ec97b95
    server: 192.168.1.253
  persistentVolumeReclaimPolicy: Delete
  storageClassName: synology
  volumeMode: Filesystem
status:
  phase: Bound

thanks @gveitmic for the explanation. 

I'll dig more into it.