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Migration ​

From ingress-nginx to Traefik ​

This guide will help you migrate your Kubernetes cluster from using ingress-nginx to Traefik as your ingress controller.

For a comprehensive, official guide with detailed instructions and troubleshooting, refer to the Traefik documentation on migrating from ingress-nginx.

Prerequisites ​

  • Kubernetes cluster with ingress-nginx installed
  • kubectl configured to access your cluster
  • kubectl-ns plugin installed
  • Access to DNS manager

Install Traefik ​

Add the Traefik Helm repository:

bash
task add-repos

Install Traefik:

bash
task install-traefik

Check that Traefik is running:

bash
kubectl get pods -n traefik

Ensure traefik is the new default.

bash
kubectl get ingressclass traefik -o jsonpath='{.metadata.annotations.ingressclass\.kubernetes\.io/is-default-class}'

List the service.

bash
kubectl get svc -n traefik

Note that the Treafik service has a different external IP address.

bash
traefik_service_ip=$(kubectl get svc -n traefik traefik -o jsonpath='{.status.loadBalancer.ingress[0].ip}')

Update Ingress Resource ​

Switch to namespace with ingress:

bash
kubectl-ns

Patch the ingress resource:

bash
kubectl patch ingress $name -p '{"spec":{"ingressClassName":"traefik"}}'

Verify the patch:

bash
kubectl get ingress $name -o yaml | grep -A1 ingressClassName

Verify that your application is accessible through Traefik:

bash
curl -I -H "Host: app.example.com" http://$traefik_service_ip

To route it externally we need to update the application's DNS entry.

You can also update all ingress resources at once.

bash
kubectl get ingress --all-namespaces

Patch all ingresses to use Traefik:

bash
kubectl get ingress --all-namespaces -o jsonpath='{range .items[*]}{.metadata.name}{" "}{.metadata.namespace}{"\n"}{end}' | while read name namespace; do kubectl patch ingress "$name" -n "$namespace" -p '{"spec":{"ingressClassName":"traefik"}}'; done

Update DNS ​

Update DNS entries of your applications to point to the new Treafik IP.

Ensure the new IP address is resolved.

bash
nslookup app.example.com 9.9.9.9

Verify that your applications is routed correctly:

bash
curl -I https://app.example.com

Upgrade Cluster Issuer ​

If you deployed a cluster issuer, update the release:

bash
task upgrade-chart clusterIssuer $values

Uninstall ingress-nginx ​

Once you've verified that Traefik is working correctly, you can uninstall ingress-nginx:

bash
kubectl-ns ingress-nginx
task uninstall-release ingress-nginx