Mastering pod lifecycle troubleshooting
The pod is the atomic unit of Kubernetes, the smallest and most fundamental building block. If you can’t get a pod to run, your application is dead on arrival. This makes pod lifecycle issues the most common and critical problems you’ll face. In this section, we will walk through the entire lifecycle of a pod, from its creation to its termination, and cover the systematic steps to diagnose failures at each stage. We begin with the very first hurdle: getting a pod scheduled onto a node.
Pod scheduling failures: The stuck Pending pod
A Pending pod is a fundamental “Day 1” problem in Kubernetes. If you can’t get a pod to schedule, nothing else can happen. Interviewers use this scenario to test your core diagnostic skills. They want to see whether you can systematically determine why the scheduler, the component responsible for placing pods onto nodes, has rejected your workload. Your ability to calmly...
