Managed NGINX ingress with the application routing add-on

  • Article

One way to route Hypertext Transfer Protocol (HTTP) and secure (HTTPS) traffic to applications running on an Azure Kubernetes Service (AKS) cluster is to use the Kubernetes Ingress object. When you create an Ingress object that uses the application routing add-on NGINX Ingress classes, the add-on creates, configures, and manages one or more Ingress controllers in your AKS cluster.

This article shows you how to deploy and configure a basic Ingress controller in your AKS cluster.

Application routing add-on with NGINX features

The application routing add-on with NGINX delivers the following:

  • Easy configuration of managed NGINX Ingress controllers based on Kubernetes NGINX Ingress controller.
  • Integration with Azure DNS for public and private zone management
  • SSL termination with certificates stored in Azure Key Vault.

For other configurations, see:

With the retirement of Open Service Mesh (OSM) by the Cloud Native Computing Foundation (CNCF), using the application routing add-on with OSM is not recommended.

Prerequisites

  • An Azure subscription. If you don't have an Azure subscription, you can create a Trial.
  • Azure CLI version 2.54.0 or later installed and configured. Run az --version to find the version. If you need to install or upgrade, see Install Azure CLI.

Limitations

  • The application routing add-on supports up to five Azure DNS zones.
  • The application routing add-on can only be enabled on AKS clusters with managed identity.
  • All global Azure DNS zones integrated with the add-on have to be in the same resource group.
  • All private Azure DNS zones integrated with the add-on have to be in the same resource group.
  • Editing the ingress-nginx ConfigMap in the app-routing-system namespace isn't supported.
  • The following snippet annotations are blocked and will prevent an Ingress from being configured: load_module, lua_package, _by_lua, location, root, proxy_pass, serviceaccount, {, }, '.

Enable application routing using Azure CLI

Enable on a new cluster

To enable application routing on a new cluster, use the az aks create command, specifying the --enable-app-routing flag.

az aks create \
    --resource-group <ResourceGroupName> \
    --name <ClusterName> \
    --location <Location> \
    --enable-app-routing \
    --generate-ssh-keys

Enable on an existing cluster

To enable application routing on an existing cluster, use the az aks approuting enable command.

az aks approuting enable --resource-group <ResourceGroupName> --name <ClusterName>

Connect to your AKS cluster

To connect to the Kubernetes cluster from your local computer, you use kubectl, the Kubernetes command-line client. You can install it locally using the az aks install-cli command. If you use the Azure Cloud Shell, kubectl is already installed.

Configure kubectl to connect to your Kubernetes cluster using the az aks get-credentials command.

az aks get-credentials --resource-group <ResourceGroupName> --name <ClusterName>

Deploy an application

The application routing add-on uses annotations on Kubernetes Ingress objects to create the appropriate resources.

  1. Create the application namespace called hello-web-app-routing to run the example pods using the kubectl create namespace command.

    kubectl create namespace hello-web-app-routing

  2. Create the deployment by copying the following YAML manifest into a new file named deployment.yaml and save the file to your local computer.

    apiVersion: apps/v1
kind: Deployment
metadata:
  name: aks-helloworld  
  namespace: hello-web-app-routing
spec:
  replicas: 1
  selector:
    matchLabels:
      app: aks-helloworld
  template:
    metadata:
      labels:
        app: aks-helloworld
    spec:
      containers:
      - name: aks-helloworld
        image: mcr.azk8s.cn/azuredocs/aks-helloworld:v1
        ports:
        - containerPort: 80
        env:
        - name: TITLE
          value: "Welcome to Azure Kubernetes Service (AKS)"

  3. Create the service by copying the following YAML manifest into a new file named service.yaml and save the file to your local computer.

    apiVersion: v1
kind: Service
metadata:
  name: aks-helloworld
  namespace: hello-web-app-routing
spec:
  type: ClusterIP
  ports:
  - port: 80
  selector:
    app: aks-helloworld

Create the Ingress object

The application routing add-on creates an Ingress class on the cluster named webapprouting.kubernetes.azure.com. When you create an Ingress object with this class, it activates the add-on.

  1. Copy the following YAML manifest into a new file named ingress.yaml and save the file to your local computer.

    apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: aks-helloworld
  namespace: hello-web-app-routing
spec:
  ingressClassName: webapprouting.kubernetes.azure.com
  rules:
  - host: <Hostname>
    http:
      paths:
      - backend:
          service:
            name: aks-helloworld
            port:
              number: 80
        path: /
        pathType: Prefix

  2. Create the cluster resources using the kubectl apply command.

    kubectl apply -f deployment.yaml -n hello-web-app-routing

    The following example output shows the created resource:

    deployment.apps/aks-helloworld created

    kubectl apply -f service.yaml -n hello-web-app-routing

    The following example output shows the created resource:

    service/aks-helloworld created

    kubectl apply -f ingress.yaml -n hello-web-app-routing

    The following example output shows the created resource:

    ingress.networking.k8s.io/aks-helloworld created

Verify the managed Ingress was created

You can verify the managed Ingress was created using the kubectl get ingress command.

kubectl get ingress -n hello-web-app-routing

The following example output shows the created managed Ingress:

NAME             CLASS                                HOSTS               ADDRESS       PORTS     AGE
aks-helloworld   webapprouting.kubernetes.azure.com   myapp.contoso.com   20.51.92.19   80, 443   4m

Remove the application routing add-on

To remove the associated namespace, use the kubectl delete namespace command.

kubectl delete namespace hello-web-app-routing

To remove the application routing add-on from your cluster, use the az aks approuting disable command.

az aks approuting disable --name myAKSCluster --resource-group myResourceGroup

Note

To avoid potential disruption of traffic into the cluster when the application routing add-on is disabled, some Kubernetes resources, including configMaps, secrets, and the deployment that runs the controller, will remain on the cluster. These resources are in the app-routing-system namespace. You can remove these resources if they're no longer needed by deleting the namespace with kubectl delete ns app-routing-system.

Next steps