Exposing a Kubernetes Kapsule ingress controller service with a Load Balancer

This page walks you through the process of deploying an NGINX ingress controller on Scaleway's Kubernetes Kapsule service. We will configure a Load Balancer that uses a persistent IP address, which is essential for maintaining consistent routing. Additionally, we will enable the PROXY protocol to preserve client information such as the original IP address and port, which is recommended for applications that need to log or act on this data.

We will explore the differences between ephemeral and persistent IP addresses, helping you understand when and why to use each type, and guide you through deploying a demo application that illustrates the entire setup.

By the end of this guide, you should have a robust and well-configured NGINX ingress controller running on Scaleway's Kubernetes platform.

Before you start

To complete the actions presented below, you must have:

• A Scaleway account logged into the console
• Owner status or IAM permissions allowing you to perform actions in the intended Organization
• Set up a Kubernetes Kapsule cluster, deploying a TRAEFIK2 ingress controller via the application library using the Easy Deploy function
• Obtained the kubeconfig file for the cluster
• Helm installed on your local machine
• Installed kubectl and the Scaleway CLI on your local machine

Overview of key concepts

Ingress controller

An ingress controller manages external HTTP/HTTPS traffic to services within a Kubernetes cluster. The NGINX ingress controller routes traffic based on ingress resource rules.

LoadBalancer service

On Scaleway Kapsule, the LoadBalancer service provisions a Scaleway Load Balancer with an external IP, exposing the ingress controller via the Scaleway Cloud Controller Manager (CCM).

Ephemeral vs. persistent IPs

• Ephemeral IP: Dynamically assigned by Scaleway when a LoadBalancer service is created. It may change if the service is deleted and recreated, requiring DNS updates.
• Persistent IP: A flexible IP reserved via the Scaleway API, CLI or console, ensuring consistency across service recreations. This is recommended for production to maintain stable DNS records.

PROXY protocol

The PROXY protocol allows the LoadBalancer to forward the client's original IP address to the ingress controller, preserving source information for logging and security.

Deploying the ingress controller

Installation prework

Kapsule clusters use a default security group (kubernetes-<cluster-id>) that blocks incoming traffic. To allow HTTP/HTTPS connections to the cluster:

1. Go to the Scaleway console and navigate to Compute > CPU & GPU Instances > Security Groups.
2. Locate the security group kubernetes-<cluster-id>.
3. Add rules to allow:
   • TCP port 80 (HTTP) from 0.0.0.0/0.
   • TCP port 443 (HTTPS) from 0.0.0.0/0.

Reserve a flexible IP

To use a persistent IP with the ingress controller:

1. Create a flexible IP using the Scaleway CLI:
   scw lb ip create

2. Note the IP address (e.g., 195.154.72.226) and IP ID for use in the LoadBalancer service.

Installing the NGINX ingress controller

Use Helm to deploy the NGINX ingress controller with Scaleway-specific configurations.

1. Add the NGINX ingress Helm repository:

   helm repo add ingress-nginx https://kubernetes.github.io/ingress-nginx
   helm repo update

2. Create a file named ingress-values.yaml with and edit the loadBalancerIP to your flexible IP:

   controller:
     service:
       type: LoadBalancer
       # Specify reserved flexible IP
       loadBalancerIP: "195.154.72.226"
       annotations:
         # Enable PROXY protocol v2
         service.beta.kubernetes.io/scw-loadbalancer-proxy-protocol-v2: "true"
         # Use hostname for cert-manager compatibility
         service.beta.kubernetes.io/scw-loadbalancer-use-hostname: "true"
     config:
       # Enable PROXY protocol in NGINX
       use-proxy-protocol: "true"
       use-forwarded-headers: "true"
       compute-full-forwarded-for: "true"

   Note

   • Replace 195.154.72.226 with your reserved flexible IP. Omitting loadBalancerIP results in an ephemeral IP.
   • The service.beta.kubernetes.io/scw-loadbalancer-proxy-protocol-v2 annotation enables PROXY protocol v2.
   • The service.beta.kubernetes.io/scw-loadbalancer-use-hostname annotation supports cert-manager HTTP01 challenges.

3. Deploy the ingress controller:

   helm install ingress-nginx ingress-nginx/ingress-nginx -f ingress-values.yaml --namespace ingress-nginx --create-namespace

4. Verify the LoadBalancer IP using kubectl:

   kubectl get svc -n ingress-nginx ingress-nginx-controller

   You will see an output similar to the following example:

   NAME                       TYPE           CLUSTER-IP      EXTERNAL-IP     PORT(S)                      AGE
   ingress-nginx-controller   LoadBalancer   10.100.0.1      195.154.72.226   80/TCP,443/TCP               5m

   Note

   • The EXTERNAL-IP should match your reserved flexible IP (e.g., 195.154.72.226).
   • If an ephemeral IP appears, verify that the loadBalancerIP field is correctly set and matches a valid Load Balancer flexible IP attached to your Scaleway Project.
   • Confirm the LoadBalancer in the Scaleway console under Network > Load Balancers.

5. Configure DNS by setting the A-Record of your domain (e.g., demo.example.com) to the flexible IP via Scaleway's Domains & DNS product or your DNS provider. Persistent IPs ensure stability and will not change as long as they are reserved.

Deploying a demo application

1. Create a file named demo-app.yaml and copy the following content into it to deploy a simple web application to test the ingress controller:

   apiVersion: apps/v1
   kind: Deployment
   metadata:
     name: demo-app
     namespace: default
   spec:
     replicas: 2
     selector:
       matchLabels:
         app: demo-app
     template:
       metadata:
         labels:
           app: demo-app
       spec:
         containers:
         - name: demo-app
           image: nginx:1.21
           ports:
           - containerPort: 80
   ---
   apiVersion: v1
   kind: Service
   metadata:
     name: demo-app
     namespace: default
   spec:
     selector:
       app: demo-app
     ports:
       - protocol: TCP
         port: 80
         targetPort: 80
   ---
   apiVersion: networking.k8s.io/v1
   kind: Ingress
   metadata:
     name: demo-app-ingress
     namespace: default
     annotations:
       nginx.ingress.kubernetes.io/rewrite-target: /
   spec:
     ingressClassName: nginx
     rules:
     - host: demo.example.com
       http:
         paths:
         - path: /
           pathType: Prefix
           backend:
             service:
               name: demo-app
               port:
                 number: 80

   Note

   • Replace demo.example.com with your domain name.

2. Apply the configuration:

   kubectl apply -f demo-app.yaml

Test the setup

1. Access the demo application:

   curl http://demo.example.com
   # or
   curl http://195.154.72.226/

2. You should see the NGINX welcome page. Verify the PROXY protocol by checking logs for the client's real IP:

   kubectl logs -n ingress-nginx -l app.kubernetes.io/name=ingress-nginx

Cleanup (optional)

Once finished, you can remove the demo application and ingress controller from your cluster:

kubectl delete -f demo-app.yaml
helm uninstall ingress-nginx -n ingress-nginx
kubectl delete namespace ingress-nginx

To release the flexible IP:

scw lb ip delete <IP-ID>