I am getting started with Kubernetes and I am trying to learn more about the liveness probe.

Some docs and articles tell the default value of failureThreshold is 3 times. And when you do not specify failureThreshold, Kubernetes will make 3 probes before restarting the container.

My question is, how many times does kubelet restarts the pod container?

Here is a sample livenessprobe-execaction.yaml:

apiVersion: v1
kind: Pod
metadata:
  labels:
    test: liveness
  name: liveness-exec
spec:
  containers:
  - name: liveness
    image: k8s.gcr.io/busybox
    args: # command to be executed when the container starts
    - /bin/sh
    - -c
    - touch /tmp/healthy; sleep 30; rm -rf /tmp/healthy; sleep 600 # during first 30 seconds there will be a file and cat will return success, when removed, a failure
    livenessProbe:
      exec:
        command: # in the first probe there will be a file within 30 seconds, and no errors
                 # and after 35 seconds a nex probe is done but the file is gone, and error will show up and machine will be restarted
                 # several restarts should happen or restarts only 3 times?
        - cat
        - /tmp/healthy
      initialDelaySeconds: 5 # kubelet waits 5 seconds before first probe
      periodSeconds: 5 # kubelet checks every 5 seconds
      #failureThreshold: 3 is the default number of times, after the 3rd liveness probe the container is restarted? forever?

After creating the pod:

$ kubectl apply -f livenessprobe-execaction.yaml

And running a watch:

$ kubectl get pod liveness-exec --watch

The output is:

    NAME            READY   STATUS    RESTARTS   AGE
    liveness-exec   1/1     Running   0          4s
    liveness-exec   1/1     Running   1          75s
    liveness-exec   1/1     Running   2          2m29s
    liveness-exec   1/1     Running   3          3m44s
    liveness-exec   1/1     Running   4          5m
    liveness-exec   1/1     Running   5          6m14s
    liveness-exec   0/1     CrashLoopBackOff   5          7m29s
    liveness-exec   1/1     Running            6          8m57s
    liveness-exec   1/1     Running            7          10m
    liveness-exec   0/1     CrashLoopBackOff   7          11m
    liveness-exec   1/1     Running            8          16m
    liveness-exec   1/1     Running            9          17m
    liveness-exec   0/1     CrashLoopBackOff   9          18m