Add support for kubeletDiskType

azure/converters/managedagentpool.go

@@ -46,6 +46,7 @@ func AgentPoolToManagedClusterAgentPoolProfile(pool containerservice.AgentPool)
 		NodePublicIPPrefixID: properties.NodePublicIPPrefixID,
 		ScaleSetPriority:     properties.ScaleSetPriority,
 		Tags:                 properties.Tags,
+		KubeletDiskType:      properties.KubeletDiskType,
 	}
 	if properties.KubeletConfig != nil {
 		agentPool.KubeletConfig = properties.KubeletConfig

azure/scope/managedmachinepool.go

@@ -179,6 +179,7 @@ func buildAgentPoolSpec(managedControlPlane *infrav1exp.AzureManagedControlPlane
 		NodePublicIPPrefixID: managedMachinePool.Spec.NodePublicIPPrefixID,
 		ScaleSetPriority:     managedMachinePool.Spec.ScaleSetPriority,
 		AdditionalTags:       managedMachinePool.Spec.AdditionalTags,
+		KubeletDiskType:      managedMachinePool.Spec.KubeletDiskType,
 	}
 
 	if managedMachinePool.Spec.OSDiskSizeGB != nil {

azure/services/agentpools/spec.go

@@ -130,6 +130,9 @@ type AgentPoolSpec struct {
 	// KubeletConfig specifies the kubelet configurations for nodes.
 	KubeletConfig *KubeletConfig `json:"kubeletConfig,omitempty"`
 
+	// KubeletDiskType specifies the kubelet disk type for each node in the pool. Allowed values are 'OS' and 'Temporary'
+	KubeletDiskType *string `json:"kubeletDiskType,omitempty"`
+
 	// AdditionalTags is an optional set of tags to add to Azure resources managed by the Azure provider, in addition to the ones added by default.
 	AdditionalTags infrav1.Tags
 }
@@ -278,6 +281,7 @@ func (s *AgentPoolSpec) Parameters(existing interface{}) (params interface{}, er
 			EnableAutoScaling:    s.EnableAutoScaling,
 			EnableUltraSSD:       s.EnableUltraSSD,
 			KubeletConfig:        kubeletConfig,
+			KubeletDiskType:      containerservice.KubeletDiskType(to.String(s.KubeletDiskType)),
 			MaxCount:             s.MaxCount,
 			MaxPods:              s.MaxPods,
 			MinCount:             s.MinCount,

config/crd/bases/infrastructure.cluster.x-k8s.io_azuremanagedmachinepools.yaml

@@ -289,6 +289,14 @@ spec:
                     - single-numa-node
                     type: string
                 type: object
+              kubeletDiskType:
+                description: 'KubeletDiskType specifies the kubelet disk type. Default
+                  to OS. Possible values include: ''OS'', ''Temporary''. Requires
+                  kubeletDisk preview feature to be set.'
+                enum:
+                - OS
+                - Temporary
+                type: string
               maxPods:
                 description: MaxPods specifies the kubelet --max-pods configuration
                   for the node pool.

docs/book/src/topics/managedcluster.md

@@ -361,6 +361,30 @@ spec:
   osDiskType: "Ephemeral"
 ```
 
+## AKS Node Pool KubeletDiskType configuration
+
+You can configure the `KubeletDiskType` value for each AKS node pool (`AzureManagedMachinePool`) that you define in your spec (see [here](https://learn.microsoft.com/en-us/rest/api/aks/agent-pools/create-or-update?tabs=HTTP#kubeletdisktype) for the official AKS documentation). There are two options to choose from: `"OS"` or `"Temporary"`.
+
+Before this feature can be used, you must register the `KubeletDisk` feature on your Azure subscription with the following az cli command.
+
+```bash
+az feature register --namespace Microsoft.ContainerService --name KubeletDisk
+```
+
+Below an example `kubeletDiskType` configuration is assigned to `agentpool0`, specifying that the emptyDir volumes, container runtime data root, and Kubelet ephemeral storage will be stored on the temporary disk:
+
+```yaml
+apiVersion: infrastructure.cluster.x-k8s.io/v1beta1
+kind: AzureManagedMachinePool
+metadata:
+  name: agentpool0
+spec:
+  mode: System
+  osDiskSizeGB: 30
+  sku: Standard_D2s_v3
+  kubeletDiskType: "Temporary"
+```
+
 ### AKS Node Pool Taints
 
 You can configure the `Taints` value for each AKS node pool (`AzureManagedMachinePool`) that you define in your spec.

exp/api/v1alpha3/azuremanagedmachinepool_conversion.go

@@ -49,6 +49,7 @@ func (src *AzureManagedMachinePool) ConvertTo(dstRaw conversion.Hub) error {
 	dst.Spec.NodePublicIPPrefixID = restored.Spec.NodePublicIPPrefixID
 	dst.Spec.ScaleSetPriority = restored.Spec.ScaleSetPriority
 	dst.Spec.AdditionalTags = restored.Spec.AdditionalTags
+	dst.Spec.KubeletDiskType = restored.Spec.KubeletDiskType
 	if restored.Spec.KubeletConfig != nil {
 		dst.Spec.KubeletConfig = restored.Spec.KubeletConfig
 	}

exp/api/v1alpha4/azuremanagedmachinepool_conversion.go

@@ -49,6 +49,7 @@ func (src *AzureManagedMachinePool) ConvertTo(dstRaw conversion.Hub) error {
 	dst.Spec.NodePublicIPPrefixID = restored.Spec.NodePublicIPPrefixID
 	dst.Spec.ScaleSetPriority = restored.Spec.ScaleSetPriority
 	dst.Spec.AdditionalTags = restored.Spec.AdditionalTags
+	dst.Spec.KubeletDiskType = restored.Spec.KubeletDiskType
 	if restored.Spec.KubeletConfig != nil {
 		dst.Spec.KubeletConfig = restored.Spec.KubeletConfig
 	}

exp/api/v1beta1/azuremanagedmachinepool_types.go

@@ -189,6 +189,12 @@ type AzureManagedMachinePoolSpec struct {
 	// KubeletConfig specifies the kubelet configurations for nodes.
 	// +optional
 	KubeletConfig *KubeletConfig `json:"kubeletConfig,omitempty"`
+
+	// KubeletDiskType specifies the kubelet disk type. Default to OS. Possible values include: 'OS', 'Temporary'.
+	// Requires kubeletDisk preview feature to be set.
+	// +kubebuilder:validation:Enum=OS;Temporary
+	// +optional
+	KubeletDiskType *string `json:"kubeletDiskType,omitempty"`
 }
 
 // ManagedMachinePoolScaling specifies scaling options.

exp/api/v1beta1/azuremanagedmachinepool_webhook.go

@@ -199,6 +199,13 @@ func (m *AzureManagedMachinePool) ValidateUpdate(oldRaw runtime.Object, client c
 		allErrs = append(allErrs, err)
 	}
 
+	if err := webhookutils.ValidateImmutable(
+		field.NewPath("Spec", "KubeletDiskType"),
+		old.Spec.KubeletDiskType,
+		m.Spec.KubeletDiskType); err != nil {
+		allErrs = append(allErrs, err)
+	}
+
 	if len(allErrs) != 0 {
 		return apierrors.NewInvalid(GroupVersion.WithKind("AzureManagedMachinePool").GroupKind(), m.Name, allErrs)
 	}