title: Kubernetes service can't communicate with each other
body: <p>I'm new with Kubernetes and I tried to create two services that can communicate with each other. The first service is a simple static web (HTML, js) with type <code>LoadBalancer</code> and the second service is a express.js backend with the type <code>ClusterIP</code>. Here's my <code>service.yaml</code> file:</p>
  <pre><code>apiVersion: v1
  kind: Service
  metadata:
    name: number-generator
  spec:
    selector:
      app: number-generator
    ports:
    - port: 3000
      targetPort: 3000
    type: ClusterIP
  ---
  apiVersion: v1
  kind: Service
  metadata:
    name: number-web
  spec:
    selector:
      app: number-web
    ports:
    - port: 80
      targetPort: 80
    type: LoadBalancer
  </code></pre>
  <p>And here's my <code>deployment.yaml</code> file:</p>
  <pre><code>apiVersion: apps/v1
  kind: Deployment
  metadata:
    name: number-generator
  spec:
    selector:
      matchLabels:
        app: number-generator
    template:
      metadata:
        labels:
          app: number-generator
      spec:
        containers:
        - name: number-generator
          image: cantdocpp/number-generator
          ports:
          - containerPort: 3000
  ---
  apiVersion: apps/v1
  kind: Deployment
  metadata:
    name: number-web
  spec:
    selector:
      matchLabels:
        app: number-web
    template:
      metadata:
        labels:
          app: number-web
      spec:
        containers:
        - name: number-web
          image: cantdocpp/number-web:v5
          ports:
          - containerPort: 80
  </code></pre>
  <p>So inside the <code>number-web</code> service which can be accessed in <code>localhost:80</code>, should access the <code>number-generator</code> API to get a random number. I tried to access it using the <code>http://number-generator/</code> and <code>http://number-generator:3000/</code>, but both of them return a network error like this:</p>
  <pre><code>GET http://number-generator/ net::ERR_NAME_NOT_RESOLVED
  </code></pre>
  <p>The error should be more or less the same wether I call <code>http://number-generator/</code> or <code>http://number-generator:3000/</code>. So how can I make this two services talks to each others ?</p>