16. Ingress
To get started with the Ingress controller, first enable the addon.
$ minikube addons enable ingress
💡 ingress is an addon maintained by Kubernetes. For any concerns contact minikube on GitHub.
You can view the list of minikube maintainers at: https://github.com/kubernetes/minikube/blob/master/OWNERS
▪ Using image registry.k8s.io/ingress-nginx/controller:v1.10.1
▪ Using image registry.k8s.io/ingress-nginx/kube-webhook-certgen:v1.4.1
▪ Using image registry.k8s.io/ingress-nginx/kube-webhook-certgen:v1.4.1
🔎 Verifying ingress addon...
🌟 The 'ingress' addon is enabled
$ kubectl get pods -A
NAMESPACE NAME READY STATUS RESTARTS AGE
ingress-nginx ingress-nginx-admission-create-btg2t 0/1 Completed 0 4m12s
ingress-nginx ingress-nginx-admission-patch-k54gf 0/1 Completed 1 4m12s
ingress-nginx ingress-nginx-controller-768f948f8f-t2wgt 1/1 Running 0 4m12s
kube-system coredns-7db6d8ff4d-xvr9l 1/1 Running 0 8h
kube-system etcd-minikube 1/1 Running 0 8h
kube-system kube-apiserver-minikube 1/1 Running 0 8h
kube-system kube-controller-manager-minikube 1/1 Running 0 8h
kube-system kube-proxy-h2mmg 1/1 Running 0 8h
kube-system kube-scheduler-minikube 1/1 Running 0 8h
kube-system storage-provisioner 1/1 Running 1 (8h ago) 8h
Note the first three entries, al belonging to the ingress-nginx namespace.
Next, create two services:
$ kubectl create deployment web --image=gcr.io/google-samples/hello-app:1.0
deployment.apps/web created
$ kubectl create deployment web2 --image=gcr.io/google-samples/hello-app:2.0
deployment.apps/web2 created
$ kubectl expose deployment web --type=NodePort --port=8080
service/web exposed
$ kubectl expose deployment web2 --type=NodePort --port=8080
service/web2 exposed
$ kubectl get all
NAME READY STATUS RESTARTS AGE
pod/web-56bb54ff6d-kx9zf 1/1 Running 0 34s
pod/web2-d8dcbdf99-ql8jb 1/1 Running 0 24s
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 8h
service/web NodePort 10.99.66.204 <none> 8080:31616/TCP 11s
service/web2 NodePort 10.111.154.113 <none> 8080:30731/TCP 7s
NAME READY UP-TO-DATE AVAILABLE AGE
deployment.apps/web 1/1 1 1 34s
deployment.apps/web2 1/1 1 1 24s
NAME DESIRED CURRENT READY AGE
replicaset.apps/web-56bb54ff6d 1 1 1 34s
replicaset.apps/web2-d8dcbdf99 1 1 1 24s
$ minikube service web --url
http://192.168.49.2:31616
$ minikube service web2 --url
http://192.168.49.2:30731
$ curl `minikube service web --url`
Hello, world!
Version: 1.0.0
Hostname: web-56bb54ff6d-kx9zf
$ curl `minikube service web2 --url`
Hello, world!
Version: 2.0.0
Hostname: web2-d8dcbdf99-ql8jb
16.1. Creating the ingress
fanout.yaml
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
name: fanout-ingress
spec:
ingressClassName: nginx
rules:
- host: minikube
http:
paths:
- path: /v1
pathType: Prefix
backend:
service:
name: web
port:
number: 8080
- path: /v2
pathType: Prefix
backend:
service:
name: web2
port:
number: 8080
$ kubectl create deployment web --image=gcr.io/google-samples/hello-app:1.0
deployment.apps/web created
$ kubectl expose deployment web --type=NodePort --port=8080
service/web exposed
$ kubectl create deployment web2 --image=gcr.io/google-samples/hello-app:2.0
deployment.apps/web2 created
$ kubectl expose deployment web2 --type=NodePort --port=8080
service/web2 exposed
$ kubectl apply -f fanout.yaml
ingress.networking.k8s.io/fanout-ingress created
$ curl --resolve "minikube:80:$( minikube ip )" -i http://minikube/v1
HTTP/1.1 200 OK
Date: Mon, 05 Aug 2024 02:35:21 GMT
Content-Type: text/plain; charset=utf-8
Content-Length: 60
Connection: keep-alive
Hello, world!
Version: 1.0.0
Hostname: web-56bb54ff6d-88g6b
$ curl --resolve "minikube:80:$( minikube ip )" -i http://minikube/v2
HTTP/1.1 200 OK
Date: Mon, 05 Aug 2024 02:35:23 GMT
Content-Type: text/plain; charset=utf-8
Content-Length: 60
Connection: keep-alive
Hello, world!
Version: 2.0.0
Hostname: web2-d8dcbdf99-ppgg8
Finally, we can add minikube to our host machine’s /etc/hosts file:
$ sudo -- bash -c "echo `minikube ip` minikube >> /etc/hosts"
$ curl http://minikube/v1
Hello, world!
Version: 1.0.0
Hostname: web-56bb54ff6d-88g6b
$ curl http://minikube/v2
Hello, world!
Version: 2.0.0
Hostname: web2-d8dcbdf99-ppgg8
16.2. Other Ingress controllers
The above setup only works on the host machine, due to the nature of the default bridge network for Minikube’s Docker container. To expose our applications to the web, we can instead use the ngrok ingress controller. However, since the recommended setup involves Helm, we will return to this later.
Other controllers are descibed at https://kubernetes.io/docs/concepts/services-networking/ingress-controllers/.