#Troubleshooting

4 posts

Where Kubernetes Gets Slow — API Server, etcd, Scheduler
4 min read

Where Kubernetes Gets Slow — API Server, etcd, Scheduler

Diagnosing the situation where workloads are fine but kubectl crawls and rollouts lag — a slow control plane. Excessive LIST/WATCH traffic hammering the API server, etcd fsync latency and database bloat, scheduler delays, and the metrics and fixes for each.

How to Choose requests and limits — Rules That Hold Up in Operations
4 min read

How to Choose requests and limits — Rules That Hold Up in Operations

Not what requests and limits mean, but what numbers to write: measurement-based request sizing, the CPU limit throttling debate, why memory limits are the default, QoS classes and eviction order, using VPA in recommendation mode, and the two failure modes — over-reservation and unlimited memory.

When HPA Doesn't Behave — 6 Common Configuration Mistakes
4 min read

When HPA Doesn't Behave — 6 Common Configuration Mistakes

Why a Kubernetes HPA fails to scale, scales too late, or oscillates all day: missing requests and what the target percentage really means, scale-up reaction time and stabilization windows, flapping, GitOps fighting over replicas, and the limits of scaling on CPU alone.

When a Pod Is Stuck in Pending — 7 Causes and the Order to Check Them
5 min read

When a Pod Is Stuck in Pending — 7 Causes and the Order to Check Them

The causes of Kubernetes Pods stuck in Pending, ordered by real-world frequency: reading the Events in describe, insufficient resources, oversized requests, nodeSelector and affinity mismatches, taints, PVC binding waits, ResourceQuota, and the cases where Cluster Autoscaler refuses to scale up.