Enable Ingress controller on Docker Desktop with WLS2 - docker

Question

Currently, I'm using Docker Desktop with WSL2 integration. I found that Docker Desktop automatically had created a cluster for me. It means I don't have to install and use Minikube or Kind to create cluster.
The problem is that, how could I enable Ingress Controller if I use "built-in" cluster from Docker Desktop?
I tried to create an Ingress to check if this work or not, but as my guess, it didn't work.
The YAML file I created as follows:
apiVersion: apps/v1
kind: Deployment
metadata:
name: webapp
spec:
minReadySeconds: 30
selector:
matchLabels:
app: webapp
replicas: 1
template:
metadata:
labels:
app: webapp
spec:
containers:
- name: webapp
image: nodejs-helloworld:v1
---
apiVersion: v1
kind: Service
metadata:
name: webapp-service
spec:
selector:
app: webapp
ports:
- name: http
port: 3000
nodePort: 30090 # only for NotPort > 30,000
type: NodePort #ClusterIP inside cluster
---
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
name: webapp-ingress
spec:
defaultBackend:
service:
name: webapp-service
port:
number: 3000
rules:
- host: ingress.local
http:
paths:
- path: /
pathType: Prefix
backend:
service:
name: webapp-service
port:
number: 3000
I tried to access ingress.local/ but it was not successful. (I added ingress.local to point to 127.0.0.1 in host file. And the webapp worked fine at kubernetes.docker.internal:30090 )
Could you please help me to know the root cause?
Thank you.

Answer 1

Finally I found the way to fix. I have to deploy ingress Nginx by command:
kubectl apply -f https://raw.githubusercontent.com/kubernetes/ingress-nginx/controller-v0.41.2/deploy/static/provider/cloud/deploy.yaml
(Follows the instruction at https://kubernetes.github.io/ingress-nginx/deploy/#docker-for-mac. It works just fine for Docker for Windows)
Now I can access http://ingress.local successfully.

Answer 2

You have to install an ingress-nginx controller on your cluster, so that your nodes will have an opened port 80/443.
Using helm (v3 - see documentation):
helm install --namespace kube-system nginx ingress-nginx --repo https://kubernetes.github.io/ingress-nginx
Using kubectl (see documentation):
kubectl apply -f https://raw.githubusercontent.com/kubernetes/ingress-nginx/controller-v0.43.0/deploy/static/provider/cloud/deploy.yaml
Then manually adding your ingresses' hostnames to /etc/hosts:
127.0.0.1 ingress.local
127.0.0.1 my.other.service.local
# ...
Then if you make a request on http://ingress.local:
the DNS resolution will route to your cluster node
then the ingress controller will serve the request on port 80
then ingress will route the request to the configured backend service
and the service will route to an available pod

Answer 3

The newest version of Docker Desktop for Windows already adds a hosts file entry: 127.0.0.1 kubernetes.docker.internal.
You had to do use kubernetes.docker.internal URL as a hostname in Ingress definition if you want to point to 127.0.0.1. This should be in the docs on this page kubernetes.github.io/ingress-nginx/deploy but there is no Docker Desktop for Windows section there.
Your files should look like this:
apiVersion: v1
kind: Service
metadata:
name: webapp-service
spec:
type: NodePort
selector:
app: webapp
ports:
- name: http
protocol: TCP
port: 3000
nodePort: 30090
Your Ingress file should look like this:
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
name: webapp-ingress
spec:
rules:
- host: kubernetes.docker.internal
http:
paths:
- path: /
backend:
serviceName: webapp-service
servicePort: http
Then you are able to connect to app using http://kubernetes.docker.internal/.
Example you can see here: wsl2-docker-for-desktop.

Answer 4

I used the Docker-Desktop version to install the nginx-ingress controller
https://kubernetes.github.io/ingress-nginx/deploy/#docker-desktop
curl http://kubernetes.docker.internal/
Offcourse I've not installed any workload yet but the default ingress controller works just fine.

Answer 5

With Kustomize you can simply use
helmCharts:
- name: ingress-nginx
releaseName: ingress-nginx
repo: https://kubernetes.github.io/ingress-nginx

Answer 6

This is just to point out that Amel Mahmuzićs comment is still valid with a recent (I used the ingress-nginx Helm Chart 4.4.2) ingress deployment.
I could not get this to work for far too long (I tried to follow the Strapi fodadvisor example with Docker Desktop build in Kubernetes instead of minikube) and always received a 404 from the ingress.
However, after using this yaml with the added annotation
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
name: main-ingress
annotations:
kubernetes.io/ingress.class: "nginx"
spec:
rules:
- host: foodadvisor.backend
http:
paths:
- path: /
pathType: Prefix
backend:
service:
name: foodadvisor-backend
port:
number: 1337
- host: foodadvisor.client
http:
paths:
- path: /
pathType: Prefix
backend:
service:
name: foodadvisor-frontend
port:
number: 3000
it worked immediately. The K82 docs mention, that this annotation is deprecated.