Container Service for Kubernetes:Expose an application with an auto-created load balancer

Use the ACK console

1. Log on to the ACK console. In the left-side navigation pane, click Clusters.

2. On the Clusters page, click your cluster name. In the left pane, choose Workloads > Deployments.

3. On the Deployments page, click Create from Image and configure the Deployment:

   1. On the Basic Information page, set Name to my-nginx and click Next.

   2. On the Container page, configure the image and port:

      Parameter	Value
      Image Name	Click Select images. On the Artifact Center tab, search for nginx and select openanolis/nginx. Click Select Image Tag, set a tag, and click Confirm.
      Port	Name: nginx, Container Port: 80

   3. On the Advanced page, keep the defaults and click Create.

Use kubectl

1. Create a file named my-nginx.yaml with the following content:

   apiVersion: apps/v1
   kind: Deployment
   metadata:
     name: my-nginx        # Deployment name
     labels:
       app: nginx
   spec:
     replicas: 2           # Number of pod replicas
     selector:
       matchLabels:
         app: nginx        # Must match the selector in the Service
     template:
       metadata:
         labels:
           app: nginx
       spec:
       #  nodeSelector:
       #    env: test-team
         containers:
         - name: nginx
           image: anolis-registry.cn-zhangjiakou.cr.aliyuncs.com/openanolis/nginx:1.14.1-8.6
           ports:
           - containerPort: 80

2. Deploy the application:

   kubectl apply -f my-nginx.yaml

3. Verify the Deployment is ready:

   kubectl get deployment my-nginx

   Expected output:

   NAME       READY   UP-TO-DATE   AVAILABLE   AGE
   my-nginx   2/2     2            2           50s

Console

1. Log on to the ACK console. In the left navigation pane, click Clusters.

2. On the Clusters page, click the name of your cluster. In the left navigation pane, click Network > Services.

3. On the Services page, click Create. In the Create Service dialog box, set the parameters for the service.

   Parameter	Description	Example
   Name	Enter a name for the service.	my-nginx-svc
   service type	Select a service type. A service supports the following network modes to handle access from different types and sources of clients: Cluster IP This type enables communication within a cluster. Service discovery among service instances is supported only when the service type is set to ClusterIP. By using a Headless Service, you can interact with other service discovery mechanisms without relying on the default ClusterIP-based service discovery and load balancing provided by Kubernetes. LoadBalancer By integrating with Alibaba Cloud Classic Load Balancer (CLB) and Network Load Balancer (NLB), you can expose applications within the cluster to external traffic. This method significantly improves application availability and performance compared to the NodePort method. Node Port This provides a convenient way for external users to access services in the cluster through the IP address and a specific port of a node. Users can connect to a NodePort service by accessing <NodeIP>:<NodePort>, but you must manually configure load balancing.	Select Server Load Balancer as the service type. Select CLB as the load balancer type and select Create Resource. In the Create CLB Instance drop-down section, adjust the settings as needed. Set the Billing Method to Pay-by-specification.
   External Traffic Policy	Set the Node Port or Server Load Balancer service type before you can configure the External Traffic Policy. For more information, see Manage services. Local: Traffic goes only to pods on the same node. Cluster: Traffic can be forwarded to pods on other nodes in the cluster.	Local
   Backend	Select the backend application to bind to the service. If you do not associate a deployment, the system does not create Endpoints objects. For more information, see services-without-selectors.	Name: app Value: nginx
   Port Mapping	Add a service port (corresponds to the port field in the Service YAML file) and a container port (corresponds to the targetPort field in the Service YAML file). The container port must match the port exposed by the backend pod.	Service Port: 80 Container Port: 80 Protocol: TCP
   annotations	Add an annotation to the service to configure load balancer parameters. For more parameters, see Configure CLB using annotations and Configure NLB using annotations. Important Do not reuse the load balancer instance of the cluster's API Server. Otherwise, cluster access may be disrupted.	In this example, the public network traffic for the service is billed on a pay-by-bandwidth basis, with a peak bandwidth of 2 Mbit/s to control traffic. The annotations are as follows: service.beta.kubernetes.io/alibaba-cloud-loadbalancer-charge-type: paybybandwidth service.beta.kubernetes.io/alibaba-cloud-loadbalancer-bandwidth: 2
   labels	Add a label to identify the service.	None
   Service Deletion Protection	Enable deletion protection for services that support critical business or handle sensitive data. This prevents accidental deletions and reduces maintenance costs. After enabling deletion protection, you must manually disable it before deleting the resource. Note To use this feature, install the policy-template-controller and gatekeeper components from the Container Security Policy add-on. Click Install Now to deploy the components.	Disabled

   After you configure the parameters, click OK.

4. After the service is created, click its name to go to its details page. In the Basic Information section, click the service's External IP, such as 39.106.XX.XX:80, to access the sample application.

   

Kubectl

1. Create a file named my-nginx-svc.yaml with the following content for the sample service.

   Set the selector to the value of matchLabels in the my-nginx.yaml sample application file, which is app: nginx in this example. This associates the service with the backend application.

   apiVersion: v1
   kind: Service
   metadata:
     labels:
       app: nginx
     name: my-nginx-svc
     namespace: default
   spec:
     ports:
     - port: 80
       protocol: TCP
       targetPort: 80
     selector:
       app: nginx
     type: LoadBalancer

2. Apply the Service:

   kubectl apply -f my-nginx-svc.yaml

3. Confirm the Service has an external IP:

   kubectl get svc my-nginx-svc

   Expected output:

   NAME           TYPE           CLUSTER-IP    EXTERNAL-IP      PORT(S)        AGE
   my-nginx-svc   LoadBalancer   172.21.5.82   39.106.XX.XX     80:30471/TCP   5m

4. Access the application:

   curl <YOUR-EXTERNAL-IP>    # Replace with the external IP from the previous step

   Expected output:

   <!DOCTYPE html>
   <html>
   <head>
   <title>Welcome to nginx!</title>
   ...
   </html>