Network load balancing
This topic shows you how to set up an L4 load balancer backed by an Azure Standard Load Balancer using Anthos clusters on Azure.
When you create a Service of type
LoadBalancer, a Anthos clusters on Azure
controller configures an
Azure Load Balancer.
Before you begin
- You must Create a cluster
kubectlto access the cluster.
Selecting a public or private load balancer
Service load balancers can be either public — having public frontend IPs — or internal— only accessible through private IPs.
By default, a new Service is public. To create an internal load
balancer, you set the
"true" in your manifest.
Choosing subnet for internal load balancers
When creating an internal load balancer, Anthos clusters on Azure needs to pick the subnet to place the load balancer in. This default service load balancer subnet is chosen from the cluster's creation parameters as follows:
- If specified and non-empty,
Alternately, you can specify the subnet to use for a given load balancer by
annotation to the Service. The value for this annotation is the subnet's name.
Creating an example LoadBalancer
You create a load balancer by creating a deployment and exposing that deployment with a service.
Create your deployment. Containers in this Deployment listen on port 50001. Save the following YAML to a file named
apiVersion: apps/v1 kind: Deployment metadata: name: my-deployment-50001 spec: selector: matchLabels: app: products department: sales replicas: 3 template: metadata: labels: app: products department: sales spec: containers: - name: hello image: "gcr.io/google-samples/hello-app:2.0" env: - name: "PORT" value: "50001"
Create the Deployment with
kubectl apply -f my-deployment-50001.yaml
Verify that three Pods are running:
kubectl get pods --selector=app=products
Create a Service of type
LoadBalancerfor your deployment. You can create an Azure Standard Load Balancer that is either public, or internal. Choose from one of the following options.
Copy one of the following manifests to a file named
apiVersion: v1 kind: Service metadata: name: my-lb-service spec: type: LoadBalancer selector: app: products department: sales ports: - protocol: TCP port: 60000 targetPort: 50001
You create an internal LoadBalancer by setting the annotation
"true". The following YAML includes this annotation.
yaml apiVersion: v1 kind: Service metadata: name: my-lb-service annotations: service.beta.kubernetes.io/azure-load-balancer-internal: "true" spec: type: LoadBalancer selector: app: products department: sales ports: - protocol: TCP port: 60000 targetPort: 50001
Create the Service with
kubectl apply -f my-lb-service.yaml
View the Service's address with
kubectl get service.
kubectl get service my-lb-service
The output will include a column
EXTERNAL-IPwith an address of the load balancer (either public or private depending how the load balancer was created).
If you have created a public load balancer you can connect to the load balancer with
curl. Replace external-ip with the address from the output of
kubectl get servicefrom the previous step.
The output resembles the following:
Hello, world! Version: 2.0.0 Hostname: my-deployment-50001-84b6dc5555-zmk7q
To remove the Service and Deployment, use
kubectl delete -f my-lb-service.yaml kubectl delete -f my-deployment-50001.yaml