Readiness in Kubernetes

Readiness Probes in Kubernetes are used to determine whether a container in a pod is ready to accept traffic. Unlike liveness probes, which check if the container is “alive” or healthy, readiness probes determine if the container is fully initialized and ready to serve requests. When a readiness probe fails, the container will be temporarily removed from the service’s endpoints, meaning it won’t receive any traffic until the readiness probe passes again.

This mechanism is particularly useful when a container requires some time for startup (e.g., loading configurations, waiting for dependencies, etc.) or becomes temporarily unready (e.g., during maintenance tasks or resource constraints).

Key Concepts:

• Readiness Probe: A probe that checks if the container is ready to start serving traffic.
• Temporary Removal from Service: If a container fails its readiness probe, it is removed from the list of endpoints, so requests are not routed to it until it becomes ready again.

Types of Readiness Probes:

1. HTTP Probes: Kubernetes sends an HTTP GET request to the container. If the response code is in the range 200-399, the probe is considered successful, meaning the container is ready to serve traffic.
2. TCP Socket Probes: Kubernetes attempts…