Kubernetes probes

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

• readinessProbe
• livenessProbe
• startupProbe

Check mechanisms:

• exec
• grpc
• httpGet: httpHeaders
• tcpSocket

kind: Deployment

apiVersion: v1
kind: Pod
metadata:
  labels:
    test: liveness
  name: liveness-exec
spec:
  containers:
  - name: liveness
    image: registry.k8s.io/busybox
    args:
    - /bin/sh
    - -c
    - touch /tmp/healthy; sleep 30; rm -f /tmp/healthy; sleep 600
    livenessProbe:
      exec:
        command:
        - cat
        - /tmp/healthy
      initialDelaySeconds: 5
      periodSeconds: 5

readinessProbe:
  httpGet:
    path: /api/health
    port: 3000

livenessProbe:
  httpGet:
    path: /api/health
    port: 3000
  initialDelaySeconds: 60
  timeoutSeconds: 30
  failureThreshold: 10

Related

• Redis values.yml
• customStartupProbe
• customLivenessProbe
• customReadinessProbe
• Kubernetes restartPolicy
• CrashLoopBackOff
• Unknown

See also

• K8s probes: readinessProbe, livenessProbe, StartupProbe, exec, gRPC, HttpGet, tcpSocket, TerminationGracePeriodSeconds
• Kubernetes deployments, strategies: kind: Deployment, Strategies: Recreate or RollingUpdate, kubectl [ create | describe | get | scale | rollout | deployment/ ], Kubernetes Canary Deployments, deployment.kubernetes.io
• K8s troubleshooting: kubectl logs, kubectl top, kubectl get events -A, kubectl describe pod, Liveness, Readiness, Kubernetes events, Pulling image, OOMKilled, ProbeWarning, Reason, FailedScheduling, errImagePull, ImagePullBackOff, Kubelet conditions: MemoryPressure, DiskPressure, KubeletHasSufficientPID, KubeletReady, kubectl [ debug | attach | exec ] kubectl cluster-info dump, SimKube, KWOK