11.2 Ingress Controller Lab Issue - Bug Found

Hi guys !

I hit what I believe is a documentation bug on LAB 11.2.
It was a good thing as I learned a lot more stuff troubleshooting (maybe this bug is there for that reason )
I followed all the steps an the Ingress was not working so I could not access the nginx by curling the ClusterIP of the service and by adding the Host header to curl like in the doc:

curl -H "Host: www.external.com" http://10.102.167.117

1 - Root cause:

The ingress.yaml file does not contain the default class for Ingress on the definition.

LOGS from Ingress Controller:

vxr@ubuntu-k8s-master:~$ kubectl logs myingress-ingress-nginx-controller-cqbt5 -v3
-------------------------------------------------------------------------------
NGINX Ingress controller
  Release:       v1.0.2
  Build:         2b8ed4511af75a7c41e52726b0644d600fc7961b
  Repository:    https://github.com/kubernetes/ingress-nginx
  nginx version: nginx/1.19.9

-------------------------------------------------------------------------------

W0928 10:33:48.752897       7 client_config.go:615] Neither --kubeconfig nor --master was specified.  Using the inClusterConfig.  This might not work.
I0928 10:33:48.753025       7 main.go:221] "Creating API client" host="https://10.96.0.1:443"
I0928 10:33:48.760687       7 main.go:265] "Running in Kubernetes cluster" major="1" minor="21" git="v1.21.1" state="clean" commit="5e58841cce77d4bc13713ad2b91fa0d961e69192" platform="linux/amd64"
I0928 10:33:49.212817       7 main.go:104] "SSL fake certificate created" file="/etc/ingress-controller/ssl/default-fake-certificate.pem"
I0928 10:33:49.230844       7 ssl.go:531] "loading tls certificate" path="/usr/local/certificates/cert" key="/usr/local/certificates/key"
I0928 10:33:49.256887       7 nginx.go:253] "Starting NGINX Ingress controller"
I0928 10:33:49.269543       7 event.go:282] Event(v1.ObjectReference{Kind:"ConfigMap", Namespace:"default", Name:"myingress-ingress-nginx-controller", UID:"11845428-96da-4338-a23f-99a916f3fc04", APIVersion:"v1", ResourceVersion:"3434117", FieldPath:""}): type: 'Normal' reason: 'CREATE' ConfigMap default/myingress-ingress-nginx-controller
I0928 10:33:50.458770       7 nginx.go:295] "Starting NGINX process"
I0928 10:33:50.458840       7 leaderelection.go:243] attempting to acquire leader lease default/ingress-controller-leader...
I0928 10:33:50.459073       7 nginx.go:315] "Starting validation webhook" address=":8443" certPath="/usr/local/certificates/cert" keyPath="/usr/local/certificates/key"
I0928 10:33:50.459341       7 controller.go:152] "Configuration changes detected, backend reload required"
I0928 10:33:50.464504       7 status.go:84] "New leader elected" identity="ingress-nginx-controller-748d8ff6c7-stgsn"
I0928 10:33:50.518415       7 controller.go:169] "Backend successfully reloaded"
I0928 10:33:50.518462       7 controller.go:180] "Initial sync, sleeping for 1 second"
I0928 10:33:50.518568       7 event.go:282] Event(v1.ObjectReference{Kind:"Pod", Namespace:"default", Name:"myingress-ingress-nginx-controller-cqbt5", UID:"45b03c4c-26d3-4246-955b-396d21ec1dfe", APIVersion:"v1", ResourceVersion:"3434201", FieldPath:""}): type: 'Normal' reason: 'RELOAD' NGINX reload triggered due to a change in configuration
I0928 10:34:25.927925       7 leaderelection.go:253] successfully acquired lease default/ingress-controller-leader
I0928 10:34:25.928006       7 status.go:84] "New leader elected" identity="myingress-ingress-nginx-controller-cqbt5"
I0928 10:37:32.933703       7 main.go:101] "successfully validated configuration, accepting" ingress="ingress-test/default"
I0928 10:37:32.938381       7 store.go:361] "Ignoring ingress because of error while validating ingress class" ingress="default/ingress-test" error="ingress does not contain a valid IngressClass"
I0928 11:00:45.760557       7 store.go:336] "Ignoring ingress because of error while validating ingress class" ingress="default/ingress-test" error="ingress does not contain a valid IngressClass"
I0928 11:06:34.098285       7 store.go:435] "ignoring ingressclass as the spec.controller is not the same of this ingress" ingressclass="external-lb"
I0928 11:06:44.600291       7 store.go:361] "Ignoring ingress because of error while validating ingress class" ingress="default/ingress-test" error="ingress does not contain a valid IngressClass"
I0928 11:08:50.621894       7 store.go:336] "Ignoring ingress because of error while validating ingress class" ingress="default/ingress-test" error="ingress does not contain a valid IngressClass"
I0928 11:09:01.521031       7 store.go:361] "Ignoring ingress because of error while validating ingress class" ingress="default/ingress-test" error="no object matching key \"external-lb\" in local store"
I0928 11:12:46.121788       7 store.go:336] "Ignoring ingress because of error while validating ingress class" ingress="default/ingress-test" error="no object matching key \"external-lb\" in local store"
I0928 11:16:56.358722       7 store.go:452] "ignoring ingressclass as the spec.controller is not the same of this ingress" ingressclass="external-lb"
I0928 11:17:38.810403       7 store.go:365] "Found valid IngressClass" ingress="default/ingress-test" ingressclass="nginx"
I0928 11:17:38.810552       7 event.go:282] Event(v1.ObjectReference{Kind:"Ingress", Namespace:"default", Name:"ingress-test", UID:"1e442104-5e27-4dc9-8e51-d9d4ab0bef95", APIVersion:"networking.k8s.io/v1", ResourceVersion:"3438329", FieldPath:""}): type: 'Normal' reason: 'Sync' Scheduled for sync
I0928 11:17:38.810867       7 controller.go:152] "Configuration changes detected, backend reload required"
I0928 11:17:38.890003       7 controller.go:169] "Backend successfully reloaded"
I0928 11:17:38.890337       7 event.go:282] Event(v1.ObjectReference{Kind:"Pod", Namespace:"default", Name:"myingress-ingress-nginx-controller-cqbt5", UID:"45b03c4c-26d3-4246-955b-396d21ec1dfe", APIVersion:"v1", ResourceVersion:"3434201", FieldPath:""}): type: 'Normal' reason: 'RELOAD' NGINX reload triggered due to a change in configuration
192.168.89.0 - - [28/Sep/2021:11:18:27 +0000] "GET / HTTP/1.1" 200 615 "-" "curl/7.58.0" 80 0.000 [default-web-one-80] [] 192.168.89.36:80 615 0.000 200 8b2e251094e3504862db879039d270e5
vxr@ubuntu-k8s-master:~$

If I list the default ingress classes:

vxr@ubuntu-k8s-master:~$ kubectl get ingressclasses.networking.k8s.io nginx
NAME    CONTROLLER             PARAMETERS   AGE
nginx   k8s.io/ingress-nginx   <none>       95m
vxr@ubuntu-k8s-master:~$

2 - Resolution

Add the default class to the ingress.yaml file

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: ingress-test
  namespace: default
spec:
  ingressClassName: nginx
  rules:
  - host: www.external.com
    http:
      paths:
      - backend:
          service:
            name: web-one
            port:
              number: 80
        path: /
        pathType: ImplementationSpecific
status:
  loadBalancer: {}

3 - Verification

vxr@ubuntu-k8s-master:~$ curl -H "Host: www.external.com" http://10.102.167.117
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
html { color-scheme: light dark; }
body { width: 35em; margin: 0 auto;
font-family: Tahoma, Verdana, Arial, sans-serif; }
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p>

<p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p>

<p><em>Thank you for using nginx.</em></p>
</body>
</html>