In this lesson, you will learn how to deploy the NGINX Ingress Controller to act as your cluster’s central gateway for managing incoming HTTP and HTTPS traffic.
The Role of the Ingress Controller
While Kubernetes Services are great for internal communication, they are often insufficient for complex external routing. The NGINX Ingress Controller sits at the edge of your cluster, functioning as a smart reverse proxy. It monitors the Kubernetes API for Ingress resources and automatically updates its internal configuration to route traffic to the correct backend Pods based on rules like hostnames or URL paths.
Deploying via Helm
The most reliable way to deploy the NGINX Ingress Controller is using the official Helm chart. This approach handles the creation of the necessary Deployment, Service (LoadBalancer), and the ConfigMaps required for the NGINX engine.
To install it in your cluster, run:
helm install ingress-nginx ingress-nginx/ingress-nginx \
--namespace ingress-nginx --create-namespace
Once installed, the controller will provision an external IP address (in cloud environments). You can verify its status by checking the pods in the ingress-nginx namespace:
kubectl get pods -n ingress-nginx
How It Functions
Once deployed, the controller runs as a Deployment inside your cluster. It watches for Ingress resources you create. For example, if you define an Ingress rule that maps app.example.com to a specific service, the controller detects this manifest, generates the corresponding NGINX nginx.conf file, and applies the routing rules immediately without requiring a restart.
This architecture decouples your application logic from networking infrastructure. Instead of managing multiple NodePort or LoadBalancer services, you use the NGINX Ingress Controller to consolidate all external entry points into a single, manageable entry point. By leveraging this controller, you can also easily implement advanced features like SSL termination, path-based routing, and request rewriting at the edge.
Key Takeaway: The NGINX Ingress Controller acts as the single entry point for your cluster, dynamically configuring itself to route external traffic to your services based on the Ingress rules you define.