Liveness Probe through C# code giving error

Question

I am trying to implement liveness probe through C# code (.Net core framework). I simply want to run a curl command inside container like this . Below is the code snippet using kubernetesClient:

IList<string> command = new List<string>();
V1Probe livnessconfig = null;
command.Add("curl http://localhost:5001/checkhealth/");
V1ExecAction execommand = new V1ExecAction(command);
livnessconfig = new V1Probe { Exec = execommand, InitialDelaySeconds = 10, PeriodSeconds = 10, TimeoutSeconds = 5, FailureThreshold = 3 };

But getting this error in pod description:

Liveness probe errored: rpc error: code = Unknown desc = failed to exec in container: failed to start exec "a80d33b5b2046b8e606ed622da7085013a725": OCI runtime exec failed: exec failed: container_linux.go:380: starting container process caused: exec: "curl http://localhost:5001/checkhealth/": stat curl http://localhost:5001/checkhealth/

Can someone let me know whether this is correct way to provide command to V1ExecAction. Its metadata implementation in K8s.Models showing that V1ExecAction take command in List:

    #region Assembly KubernetesClient, Version=3.0.0.0, Culture=neutral, PublicKeyToken=a0f90e8c9af122d

using Newtonsoft.Json;
using System.Collections.Generic;

namespace k8s.Models
{
    //
    // Summary:
    //     ExecAction describes a "run in container" action.
    public class V1ExecAction
    {
        //
        // Summary:
        //     Initializes a new instance of the V1ExecAction class.
        public V1ExecAction();
        //
        // Summary:
        //     Initializes a new instance of the V1ExecAction class.
        //
        // Parameters:
        //   command:
        //     Command is the command line to execute inside the container, the working directory
        //     for the command is root ('/') in the container's filesystem. The command is simply
        //     exec'd, it is not run inside a shell, so traditional shell instructions ('|',
        //     etc) won't work. To use a shell, you need to explicitly call out to that shell.
        //     Exit status of 0 is treated as live/healthy and non-zero is unhealthy.
        public V1ExecAction(IList<string> command = null);

        //
        // Summary:
        //     Gets or sets command is the command line to execute inside the container, the
        //     working directory for the command is root ('/') in the container's filesystem.
        //     The command is simply exec'd, it is not run inside a shell, so traditional shell
        //     instructions ('|', etc) won't work. To use a shell, you need to explicitly call
 

       //out to that shell. Exit status of 0 is treated as live/healthy and non-zero is unhealthy.
         [JsonProperty(PropertyName = "command")]
      public IList<string> Command { get; set; }
  } }

Answer 1

You need to provide commands in list. Something like below:

V1ExecAction execommand = new V1ExecAction("curl", "http://localhost:5001/checkhealth/");

Since you already an endpoint for healthcheck, you should use V1HTTPGetAction instead of V1ExecAction. In your case, V1ExecAction will always give exit status as 0 and thus liveliness check won't be correct if your app throws any errors or down.