Deploy a Windows Server container on an Azure Kubernetes Service (AKS) cluster using Azure CLI

Azure Kubernetes Service (AKS) is a managed Kubernetes service that lets you quickly deploy and manage clusters. In this article, you use Azure CLI to deploy an AKS cluster that runs Windows Server containers. You also deploy an ASP.NET sample application in a Windows Server container to the cluster.

Before you begin

This quickstart assumes a basic understanding of Kubernetes concepts. For more information, see Kubernetes core concepts for Azure Kubernetes Service (AKS).

• If you don't have an Azure account, create a free account before you begin.

• Use the Bash environment in Azure Cloud Shell. For more information, see Get started with Azure Cloud Shell.

  

• If you prefer to run CLI reference commands locally, install the Azure CLI. If you're running on Windows or macOS, consider running Azure CLI in a Docker container. For more information, see How to run the Azure CLI in a Docker container.

  • If you're using a local installation, sign in to the Azure CLI by using the az login command. To finish the authentication process, follow the steps displayed in your terminal. For other sign-in options, see Authenticate to Azure using Azure CLI.

  • When you're prompted, install the Azure CLI extension on first use. For more information about extensions, see Use and manage extensions with the Azure CLI.

  • Run az version to find the version and dependent libraries that are installed. To upgrade to the latest version, run az upgrade.

• This article requires version 2.0.64 or later of the Azure CLI. If you're using Azure Cloud Shell, the latest version is already installed there.
• Make sure that the identity you're using to create your cluster has the appropriate minimum permissions. For more details on access and identity for AKS, see Access and identity options for Azure Kubernetes Service (AKS).
• If you have multiple Azure subscriptions, select the appropriate subscription ID in which the resources should be billed using the az account set command. For more information, see How to manage Azure subscriptions – Azure CLI.

Create a resource group

An Azure resource group is a logical group in which Azure resources are deployed and managed. When you create a resource group, you're asked to specify a ___location. This ___location is where resource group metadata is stored and where your resources run in Azure if you don't specify another region during resource creation.

• Create a resource group using the az group create command. The following example creates a resource group named myResourceGroup in the WestUS2 ___location. Enter this command and other commands in this article into a BASH shell:

export RANDOM_SUFFIX=$(openssl rand -hex 3)
export REGION="canadacentral"
export MY_RESOURCE_GROUP_NAME="myAKSResourceGroup$RANDOM_SUFFIX"
az group create --name $MY_RESOURCE_GROUP_NAME --___location $REGION

Results:

{
  "id": "/subscriptions/xxxxx-xxxxx-xxxxx-xxxxx/resourceGroups/myResourceGroupxxxxx",
  "___location": "WestUS2",
  "managedBy": null,
  "name": "myResourceGroupxxxxx",
  "properties": {
    "provisioningState": "Succeeded"
  },
  "tags": null,
  "type": "Microsoft.Resources/resourceGroups"
}

Create an AKS cluster

In this section, we create an AKS cluster with the following configuration:

• The cluster is configured with two nodes to ensure it operates reliably. A node is an Azure virtual machine (VM) that runs the Kubernetes node components and container runtime.
• The --windows-admin-password and --windows-admin-username parameters set the administrator credentials for any Windows Server nodes on the cluster and must meet Windows Server password requirements.
• The node pool uses VirtualMachineScaleSets.

To create the AKS cluster with Azure CLI, follow these steps:

1. Create a username to use as administrator credentials for the Windows Server nodes on your cluster. (The original example prompted for input; in this Exec Doc, the environment variable is set non-interactively.)

export WINDOWS_USERNAME="winadmin"

2. Create a password for the administrator username you created in the previous step. The password must be a minimum of 14 characters and meet the Windows Server password complexity requirements.

export WINDOWS_PASSWORD=$(echo "P@ssw0rd$(openssl rand -base64 10 | tr -dc 'A-Za-z0-9!@#$%^&*()' | cut -c1-6)")

3. Create your cluster using the az aks create command and specify the --windows-admin-username and --windows-admin-password parameters. The following example command creates a cluster using the values from WINDOWS_USERNAME and WINDOWS_PASSWORD you set in the previous commands. A random suffix is appended to the cluster name for uniqueness.

export MY_AKS_CLUSTER="myAKSCluster$RANDOM_SUFFIX"
az aks create \
    --resource-group $MY_RESOURCE_GROUP_NAME \
    --name $MY_AKS_CLUSTER \
    --node-count 2 \
    --enable-addons monitoring \
    --generate-ssh-keys \
    --windows-admin-username $WINDOWS_USERNAME \
    --windows-admin-password $WINDOWS_PASSWORD \
    --vm-set-type VirtualMachineScaleSets \
    --network-plugin azure

After a few minutes, the command completes and returns JSON-formatted information about the cluster. Occasionally, the cluster can take longer than a few minutes to provision. Allow up to 10 minutes for provisioning.

If you get a password validation error, and the password that you set meets the length and complexity requirements, try creating your resource group in another region. Then try creating the cluster with the new resource group.

If you don't specify an administrator username and password when creating the node pool, the username is set to azureuser and the password is set to a random value. For more information, see the Windows Server FAQ

The administrator username can't be changed, but you can change the administrator password that your AKS cluster uses for Windows Server nodes using az aks update. For more information, see Windows Server FAQ.

To run an AKS cluster that supports node pools for Windows Server containers, your cluster needs to use a network policy that uses Azure CNI (advanced) network plugin. The --network-plugin azure parameter specifies Azure CNI.

Add a node pool

By default, an AKS cluster is created with a node pool that can run Linux containers. You must add another node pool that can run Windows Server containers alongside the Linux node pool.

Windows Server 2022 is the default operating system for Kubernetes versions 1.25.0 and higher. Windows Server 2019 is the default OS for earlier versions. If you don't specify a particular OS SKU, Azure creates the new node pool with the default SKU for the version of Kubernetes used by the cluster.

az aks nodepool add \
    --resource-group $MY_RESOURCE_GROUP_NAME \
    --cluster-name $MY_AKS_CLUSTER \
    --os-type Windows \
    --name npwin \
    --node-count 1

az aks nodepool add \
    --resource-group $MY_RESOURCE_GROUP_NAME \
    --cluster-name $MY_AKS_CLUSTER \
    --os-type Windows \
    --os-sku Windows2022 \
    --name npwin \
    --node-count 1

az aks nodepool add \
    --resource-group $MY_RESOURCE_GROUP_NAME \
    --cluster-name $MY_AKS_CLUSTER \
    --os-type Windows \
    --os-sku Windows2019 \
    --name npwin \
    --node-count 1

Connect to the cluster

You use kubectl, the Kubernetes command-line client, to manage your Kubernetes clusters. If you use Azure Cloud Shell, kubectl is already installed. If you want to install and run kubectl locally, call the az aks install-cli command.

1. Configure kubectl to connect to your Kubernetes cluster using the az aks get-credentials command. This command downloads credentials and configures the Kubernetes CLI to use them.

az aks get-credentials --resource-group $MY_RESOURCE_GROUP_NAME --name $MY_AKS_CLUSTER

2. Verify the connection to your cluster using the kubectl get command, which returns a list of the cluster nodes.

kubectl get nodes -o wide

The following sample output shows all nodes in the cluster. Make sure the status of all nodes is Ready:

NAME                                STATUS   ROLES   AGE   VERSION   INTERNAL-IP   EXTERNAL-IP   OS-IMAGE                         KERNEL-VERSION      CONTAINER-RUNTIME
aks-nodepool1-20786768-vmss000000   Ready    agent   22h   v1.27.7   10.224.0.4    <none>        Ubuntu 22.04.3 LTS               5.15.0-1052-azure   containerd://1.7.5-1
aks-nodepool1-20786768-vmss000001   Ready    agent   22h   v1.27.7   10.224.0.33   <none>        Ubuntu 22.04.3 LTS               5.15.0-1052-azure   containerd://1.7.5-1
aksnpwin000000                      Ready    agent   20h   v1.27.7   10.224.0.62   <none>        Windows Server 2022 Datacenter   10.0.20348.2159     containerd://1.6.21+azure

Deploy the application

A Kubernetes manifest file defines a desired state for the cluster, such as what container images to run. In this article, you use a manifest to create all objects needed to run the ASP.NET sample application in a Windows Server container. This manifest includes a Kubernetes deployment for the ASP.NET sample application and an external Kubernetes service to access the application from the internet.

The ASP.NET sample application is provided as part of the .NET Framework Samples and runs in a Windows Server container. AKS requires Windows Server containers to be based on images of Windows Server 2019 or greater. The Kubernetes manifest file must also define a node selector to tell your AKS cluster to run your ASP.NET sample application's pod on a node that can run Windows Server containers.

1. Create a file named sample.yaml and copy in the following YAML definition.

apiVersion: apps/v1
kind: Deployment
metadata:
  name: sample
  labels:
    app: sample
spec:
  replicas: 1
  template:
    metadata:
      name: sample
      labels:
        app: sample
    spec:
      nodeSelector:
        "kubernetes.io/os": windows
      containers:
      - name: sample
        image: mcr.microsoft.com/dotnet/framework/samples:aspnetapp
        resources:
          limits:
            cpu: 1
            memory: 800M
        ports:
          - containerPort: 80
  selector:
    matchLabels:
      app: sample
---
apiVersion: v1
kind: Service
metadata:
  name: sample
spec:
  type: LoadBalancer
  ports:
  - protocol: TCP
    port: 80
  selector:
    app: sample

For a breakdown of YAML manifest files, see Deployments and YAML manifests.

If you create and save the YAML file locally, then you can upload the manifest file to your default directory in CloudShell by selecting the Upload/Download files button and selecting the file from your local file system.

2. Deploy the application using the kubectl apply command and specify the name of your YAML manifest.

kubectl apply -f sample.yaml

The following sample output shows the deployment and service created successfully:

{
  "deployment.apps/sample": "created",
  "service/sample": "created"
}

Test the application

When the application runs, a Kubernetes service exposes the application front end to the internet. This process can take a few minutes to complete. Occasionally, the service can take longer than a few minutes to provision. Allow up to 10 minutes for provisioning.

1. Check the status of the deployed pods using the kubectl get pods command. Make sure all pods are Running before proceeding.

kubectl get pods

2. Monitor progress using the kubectl get service command with the --watch argument.

while true; do
  export EXTERNAL_IP=$(kubectl get service sample -o jsonpath="{.status.loadBalancer.ingress[0].ip}" 2>/dev/null)
  if [[ -n "$EXTERNAL_IP" && "$EXTERNAL_IP" != "<pending>" ]]; then
    kubectl get service sample
    break
  fi
  echo "Still waiting for external IP assignment..."
  sleep 5
done

Initially, the output shows the EXTERNAL-IP for the sample service as pending:

NAME     TYPE           CLUSTER-IP     EXTERNAL-IP       PORT(S)        AGE
sample   LoadBalancer   xx.xx.xx.xx    pending          xx:xxxx/TCP     2m

When the EXTERNAL-IP address changes from pending to an actual public IP address, use CTRL-C to stop the kubectl watch process. The following sample output shows a valid public IP address assigned to the service:

{
  "NAME": "sample",
  "TYPE": "LoadBalancer",
  "CLUSTER-IP": "10.0.37.27",
  "EXTERNAL-IP": "52.179.23.131",
  "PORT(S)": "80:30572/TCP",
  "AGE": "2m"
}

See the sample app in action by opening a web browser to the external IP address of your service after a few minutes.

Next steps

In this quickstart, you deployed a Kubernetes cluster and then deployed an ASP.NET sample application in a Windows Server container to it. This sample application is for demo purposes only and doesn't represent all the best practices for Kubernetes applications. For guidance on creating full solutions with AKS for production, see AKS solution guidance.

To learn more about AKS, and to walk through a complete code-to-deployment example, continue to the Kubernetes cluster tutorial.