Create a standby pool (Preview)

Article
06/14/2024

This article steps through creating a standby pool for Virtual Machine Scale Sets with Flexible Orchestration.

Important

Standby pools for Virtual Machine Scale Sets with Flexible Orchestration is currently in preview. Previews are made available to you on the condition that you agree to the supplemental terms of use. Some aspects of this feature may change prior to general availability (GA).

Prerequisites

Before utilizing standby pools, complete the feature registration and configure role based access controls.

Feature Registration

Register the standby pool resource provider and the standby pool preview feature with your subscription using Azure Cloud Shell. Registration can take up to 30 minutes to successfully show as registered. You can rerun the below commands to determine when the feature is successfully registered.

Register-AzResourceProvider -ProviderNamespace Microsoft.StandbyPool

Register-AzProviderFeature -FeatureName StandbyVMPoolPreview -ProviderNamespace Microsoft.StandbyPool

Alternatively, you can register directly in the Azure portal.

In the Azure portal, navigate to your subscriptions.
Select the subscription you want to enable standby pools.
Under settings, select Resource providers.
Search for Microsoft.StandbyPool and register the provider.
Under settings, select Preview features.
Search for Standby Virtual Machine Pool Preview and register the feature.

Role-based Access Control Permissions

To allow standby pools to create virtual machines, you need to assign the appropriate RBAC permissions.

In the Azure portal, navigate to your subscriptions.
Select the subscription you want to adjust RBAC permissions.
Select Access Control (IAM).
Select Add -> Add Role Assignment.
Search for Virtual Machine Contributor and highlight it. Select Next.
Click on + Select Members.
Search for Standby pool Resource Provider.
Select the standby pool Resource Provider and select Review + Assign.
Repeat the above steps and for the Network Contributor role and the Managed Identity Operator role.

If you're using images stored in Compute Gallery when deploying your scale set, also repeat the above steps for the Compute Gallery Sharing Admin role.

For more information on assigning roles, see assign Azure roles using the Azure portal.

Create a standby pool

Navigate to your Virtual Machine Scale Set
Under Availability + scale select Standby pool.
Select Manage pool.
Provide a name for your pool, provisioning state and maximum ready capacity.
Select Save.

A screenshot showing how to enable a standby pool on an existing Virtual Machine Scale Set in the Azure portal.

You can also configure a standby pool during Virtual Machine Scale Set creation by navigating to the Management tab and checking the box to enable standby pools.

A screenshot showing how to enable a standby pool during the Virtual Machine Scale Set create experience in the portal.

Create a standby pool and associate it with an existing scale set using az standby-vm-pool create.

az standby-vm-pool create \
   --resource-group myResourceGroup 
   --location eastus \
   --name myStandbyPool \
   --max-ready-capacity 20 \
   --vm-state "Deallocated" \
   --vmss-id "/subscriptions/{subscriptionID}/resourceGroups/myResourceGroup/providers/Microsoft.Compute/virtualMachineScaleSets/myScaleSet"

Create a standby pool and associate it with an existing scale set using New-AzStandbyVMPool.

New-AzStandbyVMPool `
   -ResourceGroup myResourceGroup `
   -Location eastus `
   -Name myStandbyPool `
   -MaxReadyCapacity 20 `
   -VMState "Deallocated" `
   -VMSSId "/subscriptions/{subscriptionID}/resourceGroups/myResourceGroup/providers/Microsoft.Compute/virtualMachineScaleSets/myScaleSet"

Create a standby pool and associate it with an existing scale set. Create a template and deploy it using az deployment group create or New-AzResourceGroupDeployment.

{
    "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
    "contentVersion": "1.0.0.0",
    "parameters": {
        "location": {
           "type": "string",
           "defaultValue": "east us"    
        },
        "name": {
           "type": "string",
           "defaultValue": "myStandbyPool"
        },
        "maxReadyCapacity" : {
           "type": "int",
           "defaultValue": 10
        },
        "virtualMachineState" : {
           "type": "string",
           "defaultValue": "Deallocated"
        },
        "attachedVirtualMachineScaleSetId" : {
           "type": "string",
           "defaultValue": "/subscriptions/{subscriptionID}/resourceGroups/StandbyPools/providers/Microsoft.Compute/virtualMachineScaleSets/myScaleSet"
        }
    },
    "resources": [ 
        {
            "type": "Microsoft.StandbyPool/standbyVirtualMachinePools",
            "apiVersion": "2023-12-01-preview",
            "name": "[parameters('name')]",
            "location": "[parameters('location')]",
            "properties": {
               "elasticityProfile": {
                   "maxReadyCapacity": "[parameters('maxReadyCapacity')]" 
               },
               "virtualMachineState": "[parameters('virtualMachineState')]",
               "attachedVirtualMachineScaleSetId": "[parameters('attachedVirtualMachineScaleSetId')]"
            }
        }
    ]
   }

Create a standby pool and associate it with an existing scale set. Deploy the template using az deployment group create or New-AzResourceGroupDeployment.

param location string = resourceGroup().location
param standbyPoolName string = 'myStandbyPool'
param maxReadyCapacity int = 20
@allowed([
  'Running'
  'Deallocated'
])
param vmState string = 'Deallocated'
param virtualMachineScaleSetId string = '/subscriptions/{subscriptionID}/resourceGroups/StandbyPools/providers/Microsoft.Compute/virtualMachineScaleSets/myScaleSet}'

resource standbyPool 'Microsoft.standbypool/standbyvirtualmachinepools@2023-12-01-preview' = {
  name: standbyPoolName
  location: location
  properties: {
     elasticityProfile: {
      maxReadyCapacity: maxReadyCapacity
    }
    virtualMachineState: vmState
    attachedVirtualMachineScaleSetId: virtualMachineScaleSetId
  }
}

Create a standby pool and associate it with an existing scale set using Create or Update

PUT https://management.azure.com/subscriptions/{subscriptionID}/resourceGroups/myResourceGroup/providers/Microsoft.StandbyPool/standbyVirtualMachinePools/myStandbyPool?api-version=2023-12-01-preview
{
"type": "Microsoft.StandbyPool/standbyVirtualMachinePools",
"name": "myStandbyPool",
"location": "east us",
"properties": {
	 "elasticityProfile": {
		 "maxReadyCapacity": 20
	 },
	  "virtualMachineState":"Deallocated",
	  "attachedVirtualMachineScaleSetId": "/subscriptions/{subscriptionID}/resourceGroups/myResourceGroup/providers/Microsoft.Compute/virtualMachineScaleSets/myScaleSet"
	  }
}

Next steps

Learn how to update and delete a standby pool.