Services

API objects that provide reliable network endpoints and load balancing for a pod or set of pods.

Services are used to expose pods over a network. They maintain static IP addresses and DNS records, regardless of scaling, restarts, or migrations. Services choose which pods to forward traffic to based on a set of criteria defined in the service declaration, and labels defined in the pods declaration.

types of services

• Cluster IP (default): Expose the service on the cluster's network, making it only visible to other nodes in the cluster
• Node Port: Expose the service to a static port on each node's IP
• Load Balancer: Connects to an external, cloud-based load balancer for a single, stable external IP.
• External Name: Maps to a DNS name outside the cluster without proxying the traffic
• Headless: Provides no cluster IP

examples

Here's a manifest for a simple Flask-based web service.

apiVersion: v1
kind: Service
metadata:
  name: flask-demo
  labels:
    app: flask-demo
spec:
  ports:
  - port: 80
    protocol: TCP
    name: flask-frontend
  selector:
    app: flask-demo
    tier: frontend
  type: LoadBalancer