luc.run

Exercise

Create a Pod specification podinfo.yaml with a container based on the stefanprodan/podinfo image. Name this Pod podinfo.
Add a livenessProbe that checks the port 9898 every 10 seconds after an initial delay of 30 seconds.
Add a readinessProbe that sends an HTTP GET request to the /readyz endpoint on port 9898 every 5 seconds after an initial delay of 30 seconds.
Create the Pod and ensure that the container enters the ready state after about thirty seconds.
Delete the Pod.

Documentation

https://kubernetes.io/docs/tasks/configure-pod-container/configure-liveness-readiness-startup-probes/

Solution

Create a Pod specification podinfo.yaml with a container based on the stefanprodan/podinfo image. Name this Pod podinfo.

cat <<EOF > ./podinfo.yaml
apiVersion: v1
kind: Pod
metadata:
  name: podinfo
spec:
  containers:
  - image: stefanprodan/podinfo
    name: podinfo
EOF

Note: you can also use the following imperative command to create this specification:

kubectl run podinfo --image=stefanprodan/podinfo --dry-run=client -o yaml > podinfo.yaml

Add a livenessProbe that checks port 9898 every 10 seconds after an initial delay of 30 seconds

apiVersion: v1
kind: Pod
metadata:
  name: podinfo
spec:
  containers:
  - image: stefanprodan/podinfo
    name: podinfo
    livenessProbe:
      tcpSocket:
        port: 9898
      periodSeconds: 10
      initialDelaySeconds: 30

Add a readinessProbe that sends an HTTP GET request to the /readyz endpoint on port 9898 every 5 seconds after an initial delay of 30 seconds

apiVersion: v1
kind: Pod
metadata:
  name: podinfo
spec:
  containers:
  - image: stefanprodan/podinfo
    name: podinfo
    livenessProbe:
      tcpSocket:
        port: 9898
      periodSeconds: 10
      initialDelaySeconds: 30
    readinessProbe:
      httpGet:
        path: /readyz
        port: 9898
      periodSeconds: 5
      initialDelaySeconds: 30

Create the Pod and ensure that the container enters the ready state after about thirty seconds.

Create the Pod:

kubectl apply -f podinfo.yaml

Verification:

$ kubectl get po podinfo -w
NAME      READY   STATUS    RESTARTS   AGE
...
podinfo   0/1     Running   0          20s
podinfo   1/1     Running   0          32s

Delete the Pod

kubectl delete po podinfo