Clean up the handling for .spec.provider.workers[].machine.volume.type=standard

[ialidzhikov]

gardener-attic/gardener-extensions#401 introduces the following code fragment for backwards-compatibility reasons:

gardener-extension-provider-azure/pkg/controller/worker/machines.go

Lines 306 to 315 in b4c3648

	// In the past the volume type information was not passed to the machineclass.
	// In consequence the Machine controller manager has created machines always
	// with the default volume type of the requested machine type. Existing clusters
	// respectively their worker pools could have an invalid volume configuration
	// which was not applied. To do not damage existing cluster we will set for
	// now the volume type only if it's a valid Azure volume type.
	// Otherwise we will still use the default volume of the machine type.
	if pool.Volume.Type != nil && (*pool.Volume.Type == "Standard_LRS" || *pool.Volume.Type == "StandardSSD_LRS" || *pool.Volume.Type == "Premium_LRS") {
	osDisk["type"] = *pool.Volume.Type
	}

Prior to gardener-attic/gardener-extensions#401, the azure machines were always with the default os disk belonging to the requested machine type.

We already have in place the validation that prevents creation of a new cluster with volume type != ["Standard_LRS", "StandardSSD_LRS", "Premium_LRS"].

$ k apply -f ~/bar.yaml --dry-run=server
Error from server (Forbidden): error when creating "/Users/foo/bar.yaml": shoots.core.gardener.cloud "test" is forbidden: [spec.provider.workers[0].volume.type: Unsupported value: core.Volume{Name:(*string)(nil), Type:(*string)(0xc013ff5820), VolumeSize:"50Gi", Encrypted:(*bool)(nil)}: supported values: "Standard_LRS", "StandardSSD_LRS", "Premium_LRS"]

We still have a small number of legacy Shoots which still use .spec.provider.workers[].machine.volume.type=standard. We should actively ping them to migrate (a rolling update of the Nodes will be caused by change of volume.type).

After that we can clean up the above explicit check for ["Standard_LRS", "StandardSSD_LRS", "Premium_LRS"].

/kind cleanup
/platform azure
/priority normal
/cc @dkistner

[dkistner]

I wrote a small script to detect the affected clusters and their owners:

#/bin/bash -e -x pipefail

shoot_list=$(kubectl get shoots -o json -A | jq -r '.items[] | select(.spec.provider.type == "azure") | select(.spec.provider.workers[] | .volume.type == "standard") | [.metadata.namespace,.metadata.name,.metadata.creationTimestamp] | @json' | sed s/garden-//g | uniq)

for a in $shoot_list; do
  echo "---"
  echo "Project: $(echo $a | jq -r .[0])"
  echo "Shoot: $(echo $a | jq -r .[1])"
  echo "Owner: $(kubectl get project $(echo $a | jq -r .[0]) -o json | jq -r .spec.owner.name)"
  echo "Created at $(echo $a | jq -r .[2])"
done

[dkistner]

/assign

[kon-angelo]

/remove lifecycle/rotten