I'm trying to get a very basic app running on my Kubernetes cluster. It consists of an ASP.NET Core WebAPI and a .NET Core console application that it accessing the WebAPI.

In the console application, I receive the error: "Connection Refused":

[rro-a@dh-lnx-01 ~]$ sudo kubectl exec -it synchronizer-54b47f496b-lkb67 -n pv2-test -- /bin/bash
root@synchronizer-54b47f496b-lkb67:/app# curl http://svc-coreapi/api/Synchronizations

    curl: (7) Failed to connect to svc-coreapi port 80: Connection refused

root@synchronizer-54b47f496b-lkb67:/app#

Below is my YAML for the service:

apiVersion: v1
kind: Service
metadata:
  name: svc-coreapi
  namespace: pv2-test
spec:
  ports:
  -  port: 80
     protocol: TCP
     targetPort: 80
---

The YAML for the WebAPI:

apiVersion: apps/v1
kind: Deployment
metadata:
  annotations:
  creationTimestamp: null
  labels:
     app: pv2
  name: coreapi
  namespace: pv2-test
spec:
  replicas: 1
  selector:
    matchLabels:
      app: pv2
  strategy: {}
  template:
    metadata:
      annotations:
      creationTimestamp: null
      labels:
        app: pv2
    spec:
      containers:
      - env:
        - name: DBNAME
          value: <DBNAME>
        - name: DBPASS
          value: <PASSWORD>
        - name: DBSERVER
          value: <SQLSERVER>
        - name: DBUSER
          value: <DBUSER>
        image: myrepoapi:latest
        name: coreapi
        ports:
        - containerPort: 80
        resources: {}
      restartPolicy: Always
      imagePullSecrets:
      - name: pv2-repo-cred
status: {}

The most funny thing is: When I execute kubectl expose deployment coreapi --type=NodePort --name=svc-coreapi it works, but I do not want the WebAPI exposed to the outside. Omitting the --type=NodePort reverts the type back to ClusterIP and I will get the Connection Refused again.

Can anyone tell me what I can do to resolve this issue?