Liveness Probe failing when InitialDelaySeconds not provided

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I have implemented Liveness Probe in C# based Kubernetes Application. When I am removing InitialDelaySeconds in my livenessconfig (at code level using Kubernetes Client's V1Probe):

IList<string> command = new List<string>();
V1Probe livenessconfig = null;
command.Add("curl");
command.Add("- f");
command.Add("http://localhost:5000/checkhealth/");
V1ExecAction execommand = new V1ExecAction(command);
livenessconfig = new V1Probe { Exec = execommand, PeriodSeconds = 10};

then I am seeing Liveness Probe failing in Pod description(no reason is mentioned though):

  Normal   Created    26s               kubelet            Created container App-prox
  Normal   Started    26s               kubelet            Started container App-prox
  Warning  Unhealthy  6s (x2 over 16s)  kubelet            Liveness probe failed:
  Normal   Killing    6s                kubelet            Stopping container App-prox

I don't want to give any initialdelay to my probe and want my probe to start executing command as soon as container is up. How should I manage this?

kubernetes-pod kubernetes .net-core c#
1 Answers

By providing initialDelaySeconds you basically giving enough time to your container so that your container can be up perfectly. You want your probe to start executing command as soon as your container is up, and how would you do that? by providing initialDelaySeconds.

If a container is restarted and the initialDelaySeconds parameter is not long enough or not given then probe can fail. You need to provide initialDelaySeconds so that containers can be reliably restarted, otherwise your probe will fail because of having the risk of never starting the application.

And, initialDelaySeconds parameter should be longer than maximum initialization time for your container.

Update

The kubelet uses liveness probes to know when to restart a container. There are couple of terms in liveness probe, like: periodSeconds, initialDelaySeconds. periodSeconds specifies that the kubelet should perform a liveness probe every periodSeconds seconds and the initialDelaySeconds tells the kubelet that it should wait initialDelaySeconds seconds before performing the first probe.

user_73604170
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