Create a new file called knative-service.yaml

Paste in the following text:

apiVersion: serving.knative.dev/v1 
kind: Service
metadata:
  name: serving-app 
  namespace: default 
spec:
  template:
    spec:
      containers:
        - image: bsucaciu/knative-serving:v1

Deploy Knative Service

kubectl apply -f knative-service.yaml

Check if the service has been deployed

kubectl get ksvc

Add a new entry to hosts file

Unix: /etc/hosts
Windows: C:\Windows\System32\drivers\etc\hosts

Entry value

127.0.0.1       serving-app.default.example.com

Open your preferred web browser and navigate to:

http://serving-app.default.example.com

Default Global Config

kubectl describe configmap config-autoscaler -n serving

apiVersion: v1
kind: ConfigMap
metadata:
 name: config-autoscaler
 namespace: serving
data:
 enable-scale-to-zero: "true"
 scale-to-zero-grace-period: "30s"
 scale-to-zero-pod-retention-period: "0s"
 container-concurrency-target-default: "100"
 container-concurrency-target-percentage: "0.7"
 max-scale-up-rate: "1000"
 max-scale-down-rate: "2"
 panic-window-percentage: "10"
 panic-threshold-percentage: "200"
 stable-window: "60s"
 target-burst-capacity: "200"
 requests-per-second-target-default: "200"

Check the number of running pods

kubectl get pods

Apply the new configuration

kubectl apply -f config-autoscaler.yaml

Inspect current revision(s)

kubectl get revision

Edit the knative-service.yaml file by appending the following configuration

          env:
            - name: MESSAGE
              value: Hello

Apply the updated Knative Service

kubectl apply -f knative-service.yaml

Inspect current revisions

kubectl get revision

Change the image version

        - image: bsucaciu/knative-serving:v2

Inspect current revisions

kubectl get revision

Display current route configuration

kubectl get routes 

Split traffic accross revisions

  traffic:
    - revisionName: serving-app-00001
      percent: 50
    - revisionName: serving-app-00002
      percent: 50

Apply the updated Knative Service

kubectl apply -f knative-service.yaml

Use different domains to access specific revision(s)

  traffic:
    - revisionName: serving-app-00001
      percent: 50
    - revisionName: serving-app-00002
      percent: 50
    - revisionName: serving-app-00003
      percent: 0
      tag: test

Apply the updated Knative Service

kubectl apply -f knative-service.yaml

Add a new entry to hosts file

Unix: /etc/hosts
Windows: C:\Windows\System32\drivers\etc\hosts

Entry value

127.0.0.1       test-serving-app.default.example.com

Delete revision

kubectl delete revision serving-app-00001

Delete Knative Service

kubectl delete ksvc serving-app