title: What's the difference between service type: NodePort & LoadBalancer
body: <pre><code>apiVersion: v1
  kind: Service
  metadata:
    name: nginx 
    labels:
      name: nginx
  spec:
    ports:
      # the port that this service should serve on
    - port: 80 
      targetPort: 80
      nodePort: 30000 
    selector:
      name: nginx
    type: NodePort
  </code></pre>
  
  <hr>
  
  <pre><code>apiVersion: v1
  kind: Service
  metadata:
    name: nginx 
    labels:
      name: nginx
  spec:
    ports:
      # the port that this service should serve on
    - port: 80 
      targetPort: 80
      nodePort: 30000 
    selector:
      name: nginx
    type: LoadBalancer 
  </code></pre>
  
  <p>Two methods all support loadbalancer.
  And the port range is between 30000-32000,  why?
  If I want to use port 3000, what should I do?</p>