Kubernetes is powerful—but with that power comes complexity.
Whether you're just starting or managing clusters in production, you're bound to hit issues. Here's a list of the top 10 Kubernetes problems developers and DevOps engineers run into—and how to fix them fast.
⚠️ 1. Pods Stuck in CrashLoopBackOff
💥 Problem: Pod starts → crashes → Kubernetes tries again → repeat.
🔍 Cause: Commonly due to misconfiguration environment variables, missing files, or bad image builds.
🛠️ Troubleshoot:
kubectl logs
kubectl describe pod
Check logs for stack traces or config errors. Use livenessProbe and readinessProbe wisely.
🚫 2. ImagePullBackOff or ErrImagePull
💥 Problem: Kubernetes can’t pull the container image.
🔍 Cause: Invalid image name, tag, or no access to private registry.
🛠️ Troubleshoot:
Double-check the image path (e.g., myrepo/myapp:latest)
📡 3. Services Not Exposing Pods
💥 Problem: You’ve deployed your app, but it’s unreachable.
🔍 Cause: Misconfiguration selector, port, or targetPort.
🛠️ Troubleshoot:
kubectl get svc
kubectl describe svc
Verify labels match pod labels and targetPort aligns with the container’s exposed port.
🕳️ 4. DNS Resolution Failures Inside Pods
💥 Problem: Pod can’t resolve service names (e.g., my-service.default.svc.cluster.local)
🔍 Cause: CoreDNS not working or misconfiguration.
🛠️ Troubleshoot:
kubectl get pods -n kube-system -l k8s-app=kube-dns
kubectl logs -n kube-system
Restart DNS pods, verify network policies, and ensure your cluster's DNS config is correct.
🌀 5. Pods Pending Indefinitely
💥 Problem: Pod status stays Pending forever.
🔍 Cause: Insufficient resources or missing node selectors/tolerations.
🛠️ Troubleshoot:
kubectl describe pod
kubectl get nodes
Look for messages like 0/3 nodes are available. Adjust requests/limits or update node scheduling rules.
🔐 6. Secrets or ConfigMaps Not Loaded
💥 Problem: Pod fails because environment vars or files are missing.
🔍 Cause: Misreferenced key or secret/configMap not mounted properly.
🛠️ Troubleshoot:
Verify the secret/configMap exists:
kubectl get secrets
kubectl get configmap
Check volume mounts or envFrom sections in your YAML.
🌐 7. Ingress Not Routing Traffic
💥 Problem: External traffic doesn’t reach your app.
🔍 Cause: Misconfigured ingress rules or Ingress Controller not installed.
🛠️ Troubleshoot:
kubectl get ingress
kubectl describe ingress
Make sure an ingress controller (e.g., NGINX, Traefik) is running in the cluster and that DNS records point to its external IP.
🔁 8. Rolling Deployments Hanging or Failing
💥 Problem: kubectl rollout status never completes or fails.
🔍 Cause: readinessProbes failing or insufficient replicas.
🛠️ Troubleshoot:
kubectl rollout status deployment/
kubectl describe deployment
Fix readiness probe, increase maxUnavailable, or use --timeout to get detailed failure output.
📈 9. Resource Limits Causing OOM Kills
💥 Problem: Containers get killed unexpectedly.
🔍 Cause: Exceeding memory limit.
🛠️ Troubleshoot:
kubectl describe pod
Look for OOM Killed events. Adjust your container’s memory and CPU settings:
resources:
limits:
memory: "512Mi"
cpu: "500m"
🔒 10. RBAC Denied Errors (Forbidden)
💥 Problem: You get a Forbidden error using kubectl or services can’t access APIs.
🔍 Cause: Missing or incorrect Role/ClusterRoleBinding.
🛠️ Troubleshoot:
kubectl auth can-i
kubectl describe rolebinding
Check your ServiceAccount, and ensure your RBAC policies allow the operation.
✅ Final Tips
- Use kubectl get events --sort-by='.metadata.creationTimestamp' to catch time-ordered issues.
- Always validate YAML files:
- kubectl apply --dry-run=client -f your-file.yaml
Leverage tools like:
- 📊 Lens for visual cluster management
- 🔍 K9s for terminal UI
- 📦 Stern for tailing logs across pods
💬 What About You?
- Which Kubernetes issue tripped you up the most?
- What tool or tip do you swear by for debugging?
Drop your thoughts below and let’s help each other get better at K8s! 👇