An ingress controller is the cluster’s front door: it receives external requests, applies Kubernetes ingress rules, and forwards traffic to services. For a public Spring Boot application, it can terminate TLS before forwarding the request inside the cluster. section 10.3
Use an ingress controller when centralized edge management is more practical than configuring every application separately:
- Centralize certificate storage, renewal, and HTTPS configuration instead of repeating them in every application. section 10.3 section 10.4
- Redirect HTTP requests to HTTPS and route requests for a host or path to the appropriate Kubernetes service. section 10.3
- Choose application-level TLS for standalone or internal tools, or when encryption must continue all the way into the application. section 10.4
HTTPS at the Kubernetes boundary
An Ingress resource for app.acme.com names a TLS secret, enables HTTPS redirection, and sends the root path to the acme-webapp service on port 80. An NGINX controller performs the edge termination. section 10.3
