Scheduler

kube-scheduler Not Starting: Troubleshooting Guide The kube-scheduler is a critical control plane component in Kubernetes. If it doesn’t start, pods cannot be scheduled to nodes — leaving them stuck in a Pending state. Here’s how to troubleshoot when the scheduler refuses to start. Common Symptoms kubectl get pods -n kube-system shows kube-scheduler CrashLoopBackOff or not running at all. Pods stay in Pending forever. Logs contain errors like failed to bind to port or etcd connection refused. Possible Causes and Fixes 1. Port Conflicts By default, kube-scheduler listens on 10259 (secured) and optionally 10251 (insecure). If another process is already using the port, scheduler won’t start. ...

Introduction Have you ever wondered how Kubernetes decides where to run your pods? That’s where the kube-scheduler comes into play. It’s one of the most important — yet often overlooked — components in the Kubernetes control plane. Let’s explore how it works in plain English. What is kube-scheduler? kube-scheduler is the default scheduler for Kubernetes. Its job is simple but critical: 🧠 It picks a node for every pod that doesn’t yet have a node assigned. ...