Ingress controller
- Docker & Kubernetes course
- Advanced
- Lesson 2/70
- 4 min
Learn what an Ingress controller is.
Ingress controller
An Ingress controller is a pod that watches Ingress objects and updates its own proxy configuration (nginx, Envoy, HAProxy). It isn't in the cluster by default; it must be installed. Common options: ingress-nginx, Traefik, HAProxy, the cloud providers' own controllers.
# Minikube
minikube addons enable ingress
# in general (with Helm)
helm install ingress-nginx ingress-nginx/ingress-nginx -n ingress-nginx --create-namespace
kubectl get pods -n ingress-nginxIngressClass
A cluster can have several controllers. An IngressClass defines each controller with a name; an Ingress chooses which one processes it with spec.ingressClassName. One can be marked as the default:
$ kubectl get ingressclass
NAME CONTROLLER PARAMETERS AGE
nginx k8s.io/ingress-nginx <none> 3d
spec:
ingressClassName: nginxPractice Install the controller
Write three commands: enable the ingress add-on in Minikube; list the pods in the ingress-nginx namespace; list the IngressClasses.
Starter code
# buraya yazSample solution
minikube addons enable ingress
kubectl get pods -n ingress-nginx
kubectl get ingressclassExpected output
🌟 The 'ingress' addon is enabled NAME READY STATUS RESTARTS AGE ingress-nginx-controller-7c6974c4d8-x9k2m 1/1 Running 0 60s NAME CONTROLLER PARAMETERS AGE nginx k8s.io/ingress-nginx <none> 60s
Questions and answers
Review the lesson questions together with their answers. To test yourself, solve the lesson interactively.
1 What happens if you create an Ingress without a controller installed?
- Kubernetes installs the controller itself
- The services are deleted
- The object is saved but no traffic is routed Correct answer
- It errors
Explanation: An Ingress is a request; the software fulfilling it must run separately.
2 Choose which controller processes it.
spec:
____: nginxspec:
ingressClassName: nginxExplanation: ingressClassName is the name of an IngressClass.
3 Match.
| Term | Meaning |
|---|---|
ingress-nginx |
nginx-based controller |
Traefik |
Another controller |
IngressClass |
Controller definition |
ingressClassName |
The Ingress's choice |