Ingress

A Service of type NodePort or LoadBalancer exposes one service at a time. An Ingress is different — it is a single entry point that routes HTTP and HTTPS traffic to different backend services based on the hostname and URL path. One Ingress can replace dozens of NodePort services.

For example, a single Ingress can route app.example.com/api to the API service and app.example.com/ to the frontend service, using a single external IP and port 80/443.

Prerequisites

Ingress resources are just configuration. They have no effect until an Ingress controller is installed in the cluster to read them and actually do the routing. CasOS does not install an Ingress controller automatically. ingress-nginx is the most common choice:

kubectl apply -f https://raw.githubusercontent.com/kubernetes/ingress-nginx/controller-v1.10.0/deploy/static/provider/cloud/deploy.yaml

Once the controller is running, any Ingress resources you create in CasOS will be picked up and applied.

Creating an Ingress

Open Networking → Ingress and click Add Ingress. You specify the namespace, a name, and an Ingress class name that must match your installed controller (usually nginx). Then add one or more routing rules. Each rule combines a hostname, a URL path, a path type, and a backend service name and port.

Path type controls how the path is matched. Prefix matches any URL that starts with the given path, so /api would also match /api/users. Exact matches only the literal path. ImplementationSpecific delegates the matching logic to the controller.

Deleting an Ingress

Deleting an Ingress removes all the routing rules it defined. The backend services continue running and are still reachable by other means (ClusterIP, NodePort), but the Ingress entry point stops working.