> ## Documentation Index
> Fetch the complete documentation index at: https://notes.kodekloud.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Section Introduction

> This article covers Google Cloud Networking, focusing on exposing applications, provisioning load balancers, and configuring ingress resources in Kubernetes.

Welcome to the **Google Cloud Networking** module. When architecting your applications, you must determine which services they interact with and where those services reside—whether inside your cluster or in external systems.

<Frame>
  ![The image is a diagram showing an application linked to services and their location, with icons and labels indicating the connections.](https://kodekloud.com/kk-media/image/upload/v1752875707/notes-assets/images/GKE-Google-Kubernetes-Engine-Section-Introduction/application-services-location-diagram.jpg)
</Frame>

In this lesson, we’ll cover three key topics:

1. Exposing Pods using Kubernetes Services for internal and external communication
2. Provisioning Load Balancers to distribute traffic across your cluster
3. Configuring Ingress resources to route and manage incoming requests

***

## Exposing Applications Internally with Kubernetes Services

A *Service* in Kubernetes abstracts a set of Pods and provides a stable network endpoint. This allows applications to discover and communicate with each other without tracking individual Pod IPs.

| Service Type | Description                                 | Use Case                                       |
| ------------ | ------------------------------------------- | ---------------------------------------------- |
| ClusterIP    | Internal-only IP within the cluster         | Pod-to-Pod communication, microservices calls  |
| NodePort     | Opens a static port on each cluster node    | Simple external access, debugging              |
| LoadBalancer | Provisions a cloud provider’s load balancer | Production-ready external traffic distribution |

<Callout icon="lightbulb" color="#1CB2FE">
  By default, Services use the **ClusterIP** type. Change the `type` field in your Service manifest to `NodePort` or `LoadBalancer` for external access.
</Callout>

```yaml theme={null}
apiVersion: v1
kind: Service
metadata:
  name: my-app-service
spec:
  type: ClusterIP
  selector:
    app: my-app
  ports:
    - port: 80
      targetPort: 8080
```

***

## Leveraging Load Balancers for External Traffic

To expose your Service to the internet, set `type: LoadBalancer`. Google Cloud will automatically provision a network load balancer and assign a public IP.

<Frame>
  ![The image is a diagram illustrating Google Kubernetes Engine (GKE) with steps to create services, use a load balancer, and create ingress resources.](https://kodekloud.com/kk-media/image/upload/v1752875709/notes-assets/images/GKE-Google-Kubernetes-Engine-Section-Introduction/gke-diagram-create-services-load-balancer.jpg)
</Frame>

1. **Create Service**: Define a Service of type `LoadBalancer`.
2. **Provision LB**: GKE allocates a public IP and configures forwarding rules.
3. **Distribute Traffic**: Incoming requests are balanced across healthy Pods.

```bash theme={null}
kubectl apply -f loadbalancer-service.yaml
kubectl get service my-app-service
```

***

## Routing Traffic with Ingress

An **Ingress** resource defines HTTP(S) routing rules to Services. It provides host- and path-based routing and integrates with Google Cloud HTTP(S) Load Balancers for advanced features like SSL termination and cloud CDN.

### Sample Ingress Manifest

```yaml theme={null}
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: my-app-ingress
spec:
  rules:
    - host: example.com
      http:
        paths:
          - path: /
            pathType: Prefix
            backend:
              service:
                name: my-app-service
                port:
                  number: 80
```

<Callout icon="triangle-alert" color="#FF6B6B">
  Ensure your cluster has an Ingress controller enabled (e.g., GKE Ingress) before applying Ingress resources. Otherwise, routing rules won’t take effect.
</Callout>

***

## Links and References

* [Google Kubernetes Engine (GKE)](https://cloud.google.com/kubernetes-engine/docs)
* [Kubernetes Services Documentation](https://kubernetes.io/docs/concepts/services-networking/service/)
* [Kubernetes Ingress Documentation](https://kubernetes.io/docs/concepts/services-networking/ingress/)
* [Google Cloud Load Balancing](https://cloud.google.com/load-balancing)

<CardGroup>
  <Card title="Watch Video" icon="video" cta="Learn more" href="https://learn.kodekloud.com/user/courses/gke-google-kubernetes-engine/module/e39613e2-4771-4eaa-a8cf-6360f282895a/lesson/1376eec9-59a4-4636-bed4-52241eb3e79f" />
</CardGroup>