Self-Healing Applications in Kubernetes

 

What is Self-Healing?

Self-Healing is a Kubernetes feature that automatically detects failed Pods or containers and restores the desired state by restarting or recreating them.

Why Do We Need Self-Healing?

Suppose you have 3 Pods running:

Pod-1

Pod-2

Pod-3

If Pod-2 crashes:

Pod-1

Pod-2 (Failed)

Pod-3

Kubernetes automatically creates a new Pod:

Pod-1

Pod-3

Pod-4 (New)

This will ensures the desired number of Pods is always maintained.

How Self-Healing Works

Deployment

      |

 ReplicaSet

      |

   3 Pods

      |

Pod Crashes

      |

ReplicaSet Detects Failure

      |

New Pod Created Automatically

Practical Demo

Check running Pods - kubectl get pods

Delete one Pod manually - kubectl delete pod <pod-name>

Check again - kubectl get pods

You will see Kubernetes automatically creating a new Pod.

Benefits

High Availability

Reduced Manual Intervention

Automatic Recovery

Better Reliability

Continuous Application Availability