Container Compute Service:Expose an application by using a service that automatically creates a load balancer

Notes

• The CCM configures a load balancer only for Services of type Type=LoadBalancer. The CCM does not configure load balancers for other Service types.

Important

If you change a Service's type from Type=LoadBalancer to Type!=LoadBalancer, the CCM deletes the load balancer configuration. This makes the Service inaccessible through the load balancer.

• The CCM uses a declarative API. It automatically refreshes the load balancer configuration based on the Service configuration. As a result, any configurations that you modify in the Server Load Balancer console risk being overwritten.

  Important

  Do not manually modify the configuration of a load balancer that is managed by Kubernetes in the Server Load Balancer console. Your changes may be overwritten, which can cause the Service to become inaccessible.

• You cannot change the load balancer for an existing Service of the LoadBalancer type. To use a different load balancer, you must create a new Service.

Quota limits

• The CCM creates load balancers for Services of type Type=LoadBalancer. By default, you can have up to 60 instances. If you need more than 60 instances, log on to the Quota Center console and submit an application.

• The CCM creates listeners based on the ports defined in the Service. By default, you can add up to 50 listeners to a load balancer instance. To add more listeners, log on to the Quota Center console and submit an application.

• For more information about load balancer limits, see Limits.

  To query your load balancer quotas, see Load balancer quota management.

Step 1: Deploy the sample application

You can deploy the application from the kubectl command line.

1. Create a file named my-nginx.yaml that contains the following YAML content for the sample application.

   apiVersion: apps/v1 # for versions before 1.8.0 use apps/v1beta1
   kind: Deployment
   metadata:
     name: my-nginx    # The name of the sample application.
     labels:
       app: nginx
   spec:
     replicas: 3       # The number of replicas.
     selector:
       matchLabels:
         app: nginx     # The value must match the selector of the Service that exposes this application.
     template:
       metadata:
         labels:
           app: nginx
       spec:
         containers:
         - name: nginx
           image: registry.cn-hangzhou.aliyuncs.com/acs-sample/nginx:latest     # Replace this with the actual image address. The format is <image_name:tags>.
           ports:
           - containerPort: 80                                # This port must be exposed in the Service.

2. Deploy the my-nginx sample application.

   kubectl apply -f my-nginx.yaml

3. Confirm that the sample application is in the Normal state.

   kubectl get deployment my-nginx

   Example output:

   NAME       READY   UP-TO-DATE   AVAILABLE   AGE
   my-nginx   3/3     3            3           50s

Step 2: Expose the application using a service that automatically creates a load balancer

You can create a Service of the LoadBalancer type using the console or kubectl to expose the application.