--- title: Control plane configuration options for Microsoft Azure --- # Control plane configuration options for Microsoft Azure {#cpmso-config-options-azure} You can update your control plane machines to reflect changes in your infrastructure or environment by editing values in the control plane machine set specification. When you save an update to the control plane machine set, the Control Plane Machine Set Operator updates the control plane machines according to your configured update strategy. For more information, see "Updating the control plane configuration". The following example YAML snippets show provider specification and failure domain configurations for an Azure cluster. ## Sample Azure provider specification {#cpmso-yaml-provider-spec-azure_cpmso-config-options-azure} You can update your control plane machines to reflect changes in your underlying infrastructure by editing values in the control plane machine set provider specification. The following example YAML illustrates a valid configuration for a Microsoft Azure cluster. > [!NOTE] > When you create a control plane machine set for an existing cluster, the provider specification must match the `providerSpec` configuration in the control plane machine custom resource (CR) that the installation program creates. You can omit any field that has a value set in the failure domain section of the CR. In the following example, the `` string is the infrastructure ID. The infrastructure ID matches the cluster ID that the installation program used during cluster provisioning. If you have the OpenShift CLI (`oc`) installed, you can obtain the infrastructure ID by running the following command: ```terminal $ oc get -o jsonpath='{.status.infrastructureName}{"\n"}' infrastructure cluster ``` ```yaml {title="Sample Azure providerSpec values"} apiVersion: machine.openshift.io/v1 kind: ControlPlaneMachineSet metadata: name: cluster namespace: openshift-machine-api spec: # ... template: # ... spec: providerSpec: value: acceleratedNetworking: true apiVersion: machine.openshift.io/v1beta1 credentialsSecret: name: azure-cloud-credential namespace: openshift-machine-api diagnostics: {} image: offer: "" publisher: "" resourceID: /resourceGroups/-rg/providers/Microsoft.Compute/galleries/gallery_/images/-gen2/versions/412.86.20220930 sku: "" version: "" internalLoadBalancer: -internal kind: AzureMachineProviderSpec location: managedIdentity: -identity metadata: creationTimestamp: null name: networkResourceGroup: -rg osDisk: diskSettings: {} diskSizeGB: 1024 managedDisk: storageAccountType: Premium_LRS osType: Linux publicIP: false publicLoadBalancer: resourceGroup: -rg subnet: -master-subnet userDataSecret: name: master-user-data vmSize: Standard_D8s_v3 vnet: -vnet zone: "1" ``` where: `spec.template.spec.providerSpec.value.credentialsSecret.name` : Specifies the secret name for the cluster. Do not change this value. `spec.template.spec.providerSpec.value.image` : Specifies the image details for your control plane machine set. `spec.template.spec.providerSpec.value.image.resourceID` : Specifies an image that is compatible with your instance type. The Hyper-V generation V2 images created by the installation program have a `-gen2` suffix, while V1 images have the same name without the suffix. `spec.template.spec.providerSpec.value.internalLoadBalancer` : Specifies the internal load balancer for the control plane. The `ControlPlaneMachineSet` and control plane `Machine` CRs require this field. If the field is empty, specify a valid value. `spec.template.spec.providerSpec.value.kind` : Specifies the cloud provider platform type. Do not change this value. `spec.template.spec.providerSpec.value.location` : Specifies the region to place control plane machines on. `spec.template.spec.providerSpec.value.osDisk` : Specifies the disk configuration for the control plane. `spec.template.spec.providerSpec.value.publicLoadBalancer` : Specifies the public load balancer for the control plane. > [!NOTE] > You can omit the `publicLoadBalancer` parameter on private OpenShift Container Platform clusters that have user-defined outbound routing. `spec.template.spec.providerSpec.value.subnet` : Specifies the subnet for the control plane. `spec.template.spec.providerSpec.value.userDataSecret` : Specifies the control plane user data secret. Do not change this value. `spec.template.spec.providerSpec.value.zone` : Specifies the zone configuration for clusters that use a single zone for all failure domains. > [!NOTE] > If the cluster uses a different zone for each failure domain, configure this parameter in the failure domain. If you specify this value in the provider specification when using different zones for each failure domain, the Control Plane Machine Set Operator ignores it and uses the value in the failure domain. ## Sample Azure failure domain configuration {#cpmso-yaml-failure-domain-azure_cpmso-config-options-azure} To prevent downtime for your applications due to the failure of a single Microsoft Azure region, you can configure failure domains in the control plane machine set by configuring appropriate values in the `failureDomains` section of the `ControlPlaneMachineSet` object. The control plane machine set concept of a failure domain is analogous to the Azure concept of an [*Azure availability zone*](https://learn.microsoft.com/en-us/azure/azure-web-pubsub/concept-availability-zones). The `ControlPlaneMachineSet` CR spreads control plane machines across more than one failure domain when possible. When configuring Azure failure domains in the control plane machine set, you must specify the availability zone name. An Azure cluster can use the following configurations: - One subnet for each availability zone. - One subnet that spans more than one availability zone. - More than one subnet in more than one availability zone. ```yaml {title="Sample Azure failure domain values"} apiVersion: machine.openshift.io/v1 kind: ControlPlaneMachineSet metadata: name: cluster namespace: openshift-machine-api spec: # ... template: # ... machines_v1beta1_machine_openshift_io: failureDomains: azure: - zone: "1" subnet: - zone: "2" subnet: - zone: "3" subnet: platform: Azure # ... ``` where: `spec.template.machines_v1beta1_machine_openshift_io.failureDomains.azure.zone` : Each instance of `zone` specifies an Azure availability zone for a failure domain. > [!NOTE] > If the cluster uses a single zone for all failure domains, the `zone` parameter is in the provider specification instead of in the failure domain configuration. `spec.template.machines_v1beta1_machine_openshift_io.failureDomains.azure.subnet` : Optional: Specifies the network subnet in which to create the control plane VM. When omitted, the control plane machine set uses the `subnet` value from the machine `providerSpec` template. `spec.template.machines_v1beta1_machine_openshift_io.failureDomains.platform` : Specifies the cloud provider platform name. Do not change this value. **Additional resources** {._additional-resources} - [Updating the control plane configuration](/openshift-docs-markdown/machine_management/control_plane_machine_management/cpmso-managing-machines#cpmso-feat-config-update_cpmso-managing-machines) - [Configuring Microsoft Azure features for control plane machines](/openshift-docs-markdown/machine_management/control_plane_machine_management/cpmso_provider_configurations/cpmso-supported-features-azure#cpmso-supported-features-azure)