Minikube

Configure and Start Minikube

Before installing Knative and its components, we need to create a Minikube virtual machine and deploy Kubernetes into it.

Download minikube and add it to your path.

$TUTORIAL_HOME/bin/start-minikube.sh

Minikube starting

😄  [knativetutorial] minikube v1.28.0 on Darwin 11.1
✨  Using the hyperkit driver based on user configuration
👍  Starting control plane node knativetutorial in cluster knativetutorial
🔥  Creating hyperkit VM (CPUs=6, Memory=8192MB, Disk=51200MB) ...
🐳  Preparing Kubernetes v1.23.0 on Docker 20.10.2 ...
    > kubelet.sha256: 65 B / 65 B [--------------------------] 100.00% ? p/s 0s
    > kubectl.sha256: 65 B / 65 B [--------------------------] 100.00% ? p/s 0s
    > kubeadm.sha256: 65 B / 65 B [--------------------------] 100.00% ? p/s 0s
    > kubectl: 41.98 MiB / 41.98 MiB [---------------] 100.00% 1.10 MiB p/s 38s
    > kubeadm: 37.96 MiB / 37.96 MiB [-----------] 100.00% 450.47 KiB p/s 1m26s
    > kubelet: 108.01 MiB / 108.01 MiB [---------] 100.00% 822.97 KiB p/s 2m14s
🔎  Verifying Kubernetes components...
🌟  Enabled addons: default-storageclass, storage-provisioner
🏄  Done! kubectl is now configured to use "knativetutorial" by default

Deploy Registry

minikube -p knativetutorial addons enable registry

🔎  Verifying registry addon...
🌟  The 'registry' addon is enabled

Install Knative

Deploy Custom Resource Definitions

kubectl apply \
  --filename https://github.com/knative/serving/releases/download/knative-v1.8.3/serving-crds.yaml \
  --filename https://github.com/knative/eventing/releases/download/knative-v1.8.5/eventing-crds.yaml

Now that you have installed the Knative Serving and Eventing CRDs, the following sections we will verify the CRDs by querying the api-resources.

All Knative Serving resources will be under the API group called serving.knative.dev.

serving.knative.dev

kubectl api-resources --api-group='serving.knative.dev'

NAME             SHORTNAMES      APIVERSION                    NAMESPACED   KIND
configurations   config,cfg      serving.knative.dev/v1        true         Configuration
domainmappings   dm              serving.knative.dev/v1beta1   true         DomainMapping
revisions        rev             serving.knative.dev/v1        true         Revision
routes           rt              serving.knative.dev/v1        true         Route
services         kservice,ksvc   serving.knative.dev/v1        true         Service

All Knative Eventing resources will be under the one of following API groups:

messaging.knative.dev
eventing.knative.dev
sources.knative.dev

messaging.knative.dev

kubectl api-resources --api-group='messaging.knative.dev'

NAME            SHORTNAMES   APIVERSION                 NAMESPACED   KIND
channels        ch           messaging.knative.dev/v1   true         Channel
subscriptions   sub          messaging.knative.dev/v1   true         Subscription

eventing.knative.dev

kubectl api-resources --api-group='eventing.knative.dev'

NAME         SHORTNAMES   APIVERSION                     NAMESPACED   KIND
brokers                   eventing.knative.dev/v1        true         Broker
eventtypes                eventing.knative.dev/v1beta1   true         EventType
triggers                  eventing.knative.dev/v1        true         Trigger

sources.knative.dev

kubectl api-resources --api-group='sources.knative.dev'

NAME               SHORTNAMES   APIVERSION               NAMESPACED   KIND
apiserversources                sources.knative.dev/v1   true         ApiServerSource
containersources                sources.knative.dev/v1   true         ContainerSource
pingsources                     sources.knative.dev/v1   true         PingSource
sinkbindings                    sources.knative.dev/v1   true         SinkBinding

The Knative has two main infrastructure components: controller and webhook helps in translating the Knative CRDs which are usually written YAML files, into Kubernetes objects like Deployment and Service. Apart from the controller and webhook, the Knative Serving and Eventing also install their respective functional components which are listed in the upcoming sections.

Install Knative Serving

kubectl apply \
  --filename \
  https://github.com/knative/serving/releases/download/knative-v1.8.3/serving-core.yaml

Wait for the Knative Serving deployment to complete:

kubectl rollout status deploy controller -n knative-serving
kubectl rollout status deploy activator -n knative-serving
kubectl rollout status deploy autoscaler -n knative-serving
kubectl rollout status deploy webhook -n knative-serving

A successfuly deployment should show the following pods in knative-serving namespace:

Knative Serving pods

kubectl get pods -n knative-serving

NAME                                     READY   STATUS    RESTARTS   AGE
activator-6fb68fff7b-24bsp               1/1     Running   0          23s
autoscaler-54f48f5bb7-mvvrd              1/1     Running   0          23s
controller-66cb4b556b-n8n99              1/1     Running   0          23s
domain-mapping-66f8d5bc4c-9f9c7          1/1     Running   0          23s
domainmapping-webhook-55bdf595dd-4t4w2   1/1     Running   0          23s
webhook-6d5c77f989-lf2sm                 1/1     Running   0          23s

Install Kourier Ingress Gateway

kubectl apply \
  --filename \
    https://github.com/knative/net-kourier/releases/download/knative-v1.8.1/kourier.yaml

Wait for the Ingress Gateway deployment to complete:

kubectl rollout status deploy 3scale-kourier-control -n knative-serving
kubectl rollout status deploy 3scale-kourier-gateway -n kourier-system

A successful Kourier Ingress Gateway should show the following pods in kourier-system and knative-serving:

Kourier pods

kubectl get pods --all-namespaces -l 'app in(3scale-kourier-gateway,3scale-kourier-control)'

NAMESPACE         NAME                                      READY   STATUS    RESTARTS   AGE
kourier-system    3scale-kourier-gateway-79898dffd4-qsc65   1/1     Running   1          3d10h

Now configure Knative serving to use Kourier as the ingress:

kubectl patch configmap/config-network \
  -n knative-serving \
  --type merge \
  -p '{"data":{"ingress.class":"kourier.ingress.networking.knative.dev"}}'

Install and Configure Ingress Controller

To access the Knative Serving services from the minikube host, it will be easier to have Ingress deployed and configured.

The following section will install and configure Contour as the Ingress Controller.

kubectl apply \
  --filename https://projectcontour.io/quickstart/contour.yaml

Wait for the Ingress to be deployed and running:

kubectl rollout status ds envoy -n projectcontour
kubectl rollout status deploy contour -n projectcontour

A successful rollout should list the following pods in projectcontour

kubectl get pods -n projectcontour

NAME                       READY   STATUS    RESTARTS   AGE
contour-76bb4ff6cc-8666g   1/1     Running   0          89s
contour-76bb4ff6cc-wvtpx   1/1     Running   0          89s
envoy-dszgl                2/2     Running   0          89s

Now create an Ingress to Kourier Ingress Gateway:

cat <<EOF | kubectl apply -n kourier-system -f -
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: kourier-ingress
  namespace: kourier-system
spec:
  rules:
  - http:
     paths:
       - path: /
         pathType: Prefix
         backend:
           service:
             name: kourier
             port:
               number: 80
EOF

ingress.networking.k8s.io/kourier-ingress created

Configure Knative to use the kourier-ingress Gateway:

ksvc_domain="\"data\":{\""$(minikube -p knativetutorial ip)".nip.io\": \"\"}"
kubectl patch configmap/config-domain \
    -n knative-serving \
    --type merge \
    -p "{$ksvc_domain}"

configmap/config-domain patched

Install Knative Eventing

kubectl apply \
  --filename \
  https://github.com/knative/eventing/releases/download/knative-v1.8.5/eventing-core.yaml \
  --filename \
  https://github.com/knative/eventing/releases/download/knative-v1.8.5/in-memory-channel.yaml \
  --filename \
  https://github.com/knative/eventing/releases/download/knative-v1.8.5/mt-channel-broker.yaml

Like Knative Serving deployment, Knative Eventing deployment will also take few minutes to complete, check the status of the deployment using:

kubectl rollout status deploy eventing-controller -n knative-eventing
kubectl rollout status deploy eventing-webhook  -n knative-eventing
kubectl rollout status deploy imc-controller  -n knative-eventing
kubectl rollout status deploy imc-dispatcher -n knative-eventing
kubectl rollout status deploy mt-broker-controller -n knative-eventing
kubectl rollout status deploy mt-broker-filter -n knative-eventing
kubectl rollout status deploy mt-broker-filter -n knative-eventing

A successful deployment should show the following pods in knative-eventing namespace:

Knative eventing pods

kubectl get pods -n knative-eventing

NAME                                    READY   STATUS    RESTARTS   AGE
eventing-controller-56ccd89cd8-w9wmm    1/1     Running   0          26s
eventing-webhook-76b66cd56c-n2dqj       1/1     Running   0          26s
imc-controller-6c8cfbb558-zvglm         1/1     Running   0          25s
imc-dispatcher-b8bf96b6d-mpltl          1/1     Running   0          25s
mt-broker-controller-7dfb75f5cc-zv5jr   1/1     Running   0          25s
mt-broker-filter-8799894b4-fhk5z        1/1     Running   0          25s
mt-broker-ingress-685f5554c-mbpbd       1/1     Running   0          25s

Create Tutorial namespace

All the tutorial exercises will be deployed in namespace called knativetutorial:

kubectl create namespace knativetutorial

In order not to worry about the namespace used, will set it up as as current context:

kubectl config set-context --current --namespace=knativetutorial

The kubens utility installed as part of kubectx allows for easy switching between Kubernetes namespaces.

kubens knativetutorial