Let's check Service Types

Before we bring up the frontend service, let’s take a look at the service types we are using: This is kubernetes/service.yaml for our frontend service:

apiVersion: v1
kind: Service
metadata:
  name: ecsdemo-frontend
spec:
  selector:
    app: ecsdemo-frontend
  type: LoadBalancer
  ports:
   -  protocol: TCP
      port: 80
      targetPort: 3000

Notice type: LoadBalancer: This will configure an ELB to handle incoming traffic to this service.

Compare this to kubernetes/service.yaml for one of our backend services:

apiVersion: v1
kind: Service
metadata:
  name: ecsdemo-nodejs
spec:
  selector:
    app: ecsdemo-nodejs
  ports:
   -  protocol: TCP
      port: 80
      targetPort: 3000

Notice there is no specific service type described. When we check the kubernetes documentation we find that the default type is ClusterIP. This Exposes the service on a cluster-internal IP. Choosing this value makes the service only reachable from within the cluster.