How to start a service and access it in minikube

Question

I deployed a web app in minikube.

Deployment:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: myapp
spec:
  replicas: 3
  selector:
    matchLabels:
      app: maypp
  template:
    metadata:
      labels:
        app: myapp
    spec:
      containers:
        - name: myapp
          image: myapp
          imagePullPolicy: Never
          ports:
          - containerPort: 8080
      restartPolicy: Always

Service:

apiVersion: v1
kind: Service
metadata:
  name: myservice
spec:
  type: NodePort
  ports:
  - port: 8080

After kubectl apply -f . to deploy, all of them are running.

kubectl get po
NAMESPACE   NAME                       READY   STATUS    RESTARTS   AGE
default     myapp-5d042b65c8-h7kag     1/1     Running   0          10m

kubectl get svc
NAMESPACE   NAME        TYPE       CLUSTER-IP     EXTERNAL-IP   PORT(S)                  AGE
default     myservice   NodePort   10.102.128.35  <none>        8080:32212/TCP           10m

Run minikube service to open service in browser:

minikube service myservice
|----------------|--------------------|-------------|---------------------------|
|   NAMESPACE    |        NAME        | TARGET PORT |            URL            |
|----------------|--------------------|-------------|---------------------------|
|   default      | myservice          |        8080 | http://192.168.49.2:32212 |
|----------------|--------------------|-------------|---------------------------|
🏃  Starting tunnel for service myservice.
|----------------|--------------------|-------------|------------------------|
|   NAMESPACE    |        NAME        | TARGET PORT |          URL           |
|----------------|--------------------|-------------|------------------------|
|   default      | myservice          |             | http://127.0.0.1:55401 |
|----------------|--------------------|-------------|------------------------|
🎉  Opening service default/myservice in default browser...

In browser, I can't access my app with both http://192.168.49.2:32212 and http://127.0.0.1:55401. Even http://127.0.0.1:8080.

From the pod's log, the web server in the container is running:

kubectl logs -f myapp-5d042b65c8-h7kag

...
____________________________________O/_______
                                    O\
⇨ http server started on [::]:8080

But didn't get the way to access the endpoint correctly. So there isn't any traffic happened.

If I deploy the container with docker, it works with http://127.0.0.1:8080.

Answer 1

The problem is the missing selector field in the Service.

apiVersion: v1
kind: Service
metadata:
  name: myservice
spec:
  type: NodePort
  selector:
    app: myapp
  ports:
  - port: 8080

Services route the traffic to the pods based on the selector defined in the service spec that match to the labels defined on the pods.

From the defining-a-service section of the docs:

The controller for the Service selector continuously scans for Pods that match its selector, and then POSTs any updates to an Endpoint object also named "my-service".