Mapping incoming port in kubernetes service to different port on docker container
I found that I needed to add some arguments to my second command:
kubectl expose deployment test-app --type="LoadBalancer" --target-port=3000 --port=80This creates a service which directs incoming http traffic (on port 80) to its pods on port 3000.
A nicer way to do this whole thing is with yaml files service.yaml and deployment.yaml and calling
kubectl create -f deployment.yamlkubectl create -f service.yamlwhere the files have these contents
# deployment.yamlapiVersion: extensions/v1beta1kind: Deploymentmetadata: name: app-deploymentspec: replicas: 2 template: metadata: labels: app: test-app spec: containers: - name: user-app image: eu.gcr.io/myproject/my_app ports: - containerPort: 3000and
# service.yamlapiVersion: v1kind: Servicemetadata: name: app-servicespec: selector: app: test-app ports: - port: 80 targetPort: 3000 type: LoadBalancerNote that the selector of the service must match the label of the deployment.