Services & Ingress

In Kubernetes, pods are ephemeral — they can be created, destroyed, and rescheduled at any time. Services provide a stable network endpoint for accessing a set of pods, while Ingress provides HTTP/HTTPS routing for external traffic. On GKE, both integrate deeply with Google Cloud Load Balancing.

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Kubernetes Services

A Service is an abstraction that defines a logical set of pods and a policy for accessing them. Services provide stable IP addresses and DNS names that do not change as pods come and go.

Service Types

Type	Description	Use Case
ClusterIP	Internal-only IP, accessible within the cluster	Service-to-service communication
NodePort	Exposes the service on each node's IP at a static port	Testing, limited external access
LoadBalancer	Creates a Google Cloud Network Load Balancer	Direct external access to a service
ExternalName	Maps to an external DNS name	Accessing external services by name
Headless	No ClusterIP — returns pod IPs directly via DNS	StatefulSet discovery, custom load balancing

ClusterIP Service

apiVersion: v1
kind: Service
metadata:
  name: backend-api
spec:
  type: ClusterIP
  selector:
    app: backend-api
  ports:
    - port: 80
      targetPort: 8080
      protocol: TCP

LoadBalancer Service

When you create a Service of type LoadBalancer on GKE, it automatically provisions a Google Cloud Network Load Balancer:

apiVersion: v1
kind: Service
metadata:
  name: web-frontend
spec:
  type: LoadBalancer
  selector:
    app: web-frontend
  ports:
    - port: 80
      targetPort: 8080
      protocol: TCP

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GKE Ingress

Ingress provides HTTP/HTTPS routing from outside the cluster to services inside the cluster. On GKE, the Ingress controller creates a Google Cloud HTTP(S) Load Balancer.

Ingress Features

Feature	Description
Path-based routing	Route /api to one service, /web to another
Host-based routing	Route api.example.com to one service, web.example.com to another
TLS termination	Terminate HTTPS at the load balancer with managed certificates
Health checks	Automatic health check configuration for backends
Cloud CDN	Enable content caching at Google's edge
Cloud Armor	WAF and DDoS protection

Example Ingress