Install the Kubernetes Event-driven Autoscaling (KEDA) add-on using an ARM template

Article
11/07/2023

This article shows you how to deploy the Kubernetes Event-driven Autoscaling (KEDA) add-on to Azure Kubernetes Service (AKS) using an ARM template.

Important

Your cluster Kubernetes version determines what KEDA version will be installed on your AKS cluster. To see which KEDA version maps to each AKS version, see the AKS managed add-ons column of the Kubernetes component version table.

For GA Kubernetes versions, AKS offers full support of the corresponding KEDA minor version in the table. Kubernetes preview versions and the latest KEDA patch are partially covered by customer support on a best-effort basis. As such, these features aren't meant for production use. For more information, see the following support articles:

Before you begin

You need an Azure subscription. If you don't have an Azure subscription, you can create a free account.
You need the Azure CLI installed.
This article assumes you have an existing Azure resource group. If you don't have an existing resource group, you can create one using the az group create command.
Ensure you have firewall rules configured to allow access to the Kubernetes API server. For more information, see Outbound network and FQDN rules for Azure Kubernetes Service (AKS) clusters.
Create an SSH key pair.

Note

If you're using Microsoft Entra Workload ID and you enable KEDA before Workload ID, you need to restart the KEDA operator pods so the proper environment variables can be injected:

Restart the pods by running kubectl rollout restart deployment keda-operator -n kube-system.
Obtain KEDA operator pods using kubectl get pod -n kube-system and finding pods that begin with keda-operator.
Verify successful injection of the environment variables by running kubectl describe pod <keda-operator-pod> -n kube-system. Under Environment, you should see values for AZURE_TENANT_ID, AZURE_FEDERATED_TOKEN_FILE, and AZURE_AUTHORITY_HOST.

Create an SSH key pair

Navigate to the Azure Cloud Shell.

Create an SSH key pair using the az sshkey create command.

az sshkey create --name <sshkey-name> --resource-group <resource-group-name>

Enable the KEDA add-on with an ARM template

Deploy the ARM template for an AKS cluster.
Select Edit template.
Enable the KEDA add-on by specifying the workloadAutoScalerProfile field in the ARM template, as shown in the following example:
```
    "workloadAutoScalerProfile": {
        "keda": {
            "enabled": true
        }
    }
```
Select Save.
Update the required values for the ARM template:
- Subscription: Select the Azure subscription to use for the deployment.
- Resource group: Select the resource group to use for the deployment.
- Region: Select the region to use for the deployment.
- Dns Prefix: Enter a unique DNS name to use for the cluster.
- Linux Admin Username: Enter a username for the cluster.
- SSH public key source: Select Use existing key stored in Azure.
- Store Keys: Select the key pair you created earlier in the article.
Select Review + create > Create.

Connect to your AKS cluster

To connect to the Kubernetes cluster from your local device, you use kubectl, the Kubernetes command-line client.

If you use the Azure Cloud Shell, kubectl is already installed. You can also install it locally using the az aks install-cli command.

Configure kubectl to connect to your Kubernetes cluster, use the az aks get-credentials command. The following example gets credentials for the AKS cluster named MyAKSCluster in the MyResourceGroup:

az aks get-credentials --resource-group MyResourceGroup --name MyAKSCluster

Example deployment

The following snippet is a sample deployment that creates a cluster with KEDA enabled with a single node pool comprised of three DS2_v5 nodes.

{
    "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
    "contentVersion": "1.0.0.0",
    "resources": [
        {
            "apiVersion": "2023-03-01",
            "dependsOn": [],
            "type": "Microsoft.ContainerService/managedClusters",
            "location": "westcentralus",
            "name": "myAKSCluster",
            "properties": {
                "kubernetesVersion": "1.27",
                "enableRBAC": true,
                "dnsPrefix": "myAKSCluster",
                "agentPoolProfiles": [
                    {
                        "name": "agentpool",
                        "osDiskSizeGB": 200,
                        "count": 3,
                        "enableAutoScaling": false,
                        "vmSize": "Standard_D2S_v5",
                        "osType": "Linux",
                        "type": "VirtualMachineScaleSets",
                        "mode": "System",
                        "maxPods": 110,
                        "availabilityZones": [],
                        "nodeTaints": [],
                        "enableNodePublicIP": false
                    }
                ],
                "networkProfile": {
                    "loadBalancerSku": "standard",
                    "networkPlugin": "kubenet"
                },
                "workloadAutoScalerProfile": {
                    "keda": {
                        "enabled": true
                    }
                }
            },
            "identity": {
                "type": "SystemAssigned"
            }
        }
    ]
}

Start scaling apps with KEDA

You can autoscale your apps with KEDA using custom resource definitions (CRDs). For more information, see the KEDA documentation.

Remove resources

Remove the resource group and all related resources using the az group delete command.
```
az group delete --name <resource-group-name>
```

Next steps

This article showed you how to install the KEDA add-on on an AKS cluster, and then verify that it's installed and running. With the KEDA add-on installed on your cluster, you can deploy a sample application to start scaling apps.

For information on KEDA troubleshooting, see Troubleshoot the Kubernetes Event-driven Autoscaling (KEDA) add-on.

To learn more, view the upstream KEDA docs.