🧠 Concept 19: Troubleshooting (Debugging Kubernetes like a PRO 💯🔥)




🚀 1. Core Idea (1-line)
👉 Troubleshooting in Kubernetes = systematically finding where the chain is broken
🧠 2. Golden Rule (VERY IMPORTANT 🔥)
👉 Always debug in this order:
Pod → Container → Node → Service → Network → Config⚙️ 3. Step-by-Step Debugging Flow (CKA GOLD 🔥)
🟢 Step 1: Check Pod Status
kubectl get podsLook for:
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CrashLoopBackOff 💀
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Pending ⏳
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ImagePullBackOff 📦
🔍 Step 2: Describe Pod (MOST IMPORTANT 🔥)
kubectl describe pod <name>👉 Shows:
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Events
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Scheduling issues
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Errors
📜 Step 3: Check Logs
kubectl logs <pod>👉 For multi-container:
kubectl logs <pod> -c <container>🖥️ Step 4: Exec into Pod
kubectl exec -it <pod> -- /bin/bash👉 Check:
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Files
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Env variables
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App behavior
⚠️ 4. Common Errors & Fixes (VERY IMPORTANT 🔥)
💀 CrashLoopBackOff
👉 Causes:
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App crash
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Wrong config
👉 Fix:
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Check logs
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Fix env/config
📦 ImagePullBackOff
👉 Causes:
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Wrong image name
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Private repo
👉 Fix:
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Correct image
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Add imagePullSecrets
⏳ Pending Pod
👉 Causes:
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No resources
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Node constraints
👉 Fix:
- Check:
kubectl describe pod <name>💀 OOMKilled
👉 Cause:
- Memory limit exceeded
👉 Fix:
- Increase memory limit
🌐 5. Service Debugging
kubectl get svc
kubectl describe svc <name>Check:
- Selector matches pods ❗
🔗 6. Networking Debug
Inside pod:
curl <service-name>
ping <service-name>👉 If fails:
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DNS issue
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Service issue
🧠 7. Node-Level Debug
kubectl get nodes
kubectl describe node <node>Check:
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Resource pressure
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Node status
📊 8. Events (VERY IMPORTANT 🔥)
kubectl get events👉 Shows cluster-level issues
💥 9. Real-world Debug Example (🔥)
Problem:
👉 ML API not responding
Debug:
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Pod running?
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Logs show error?
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Service connected?
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Ingress routing correct?
👉 Find break in chain
⚠️ 10. Common Mistakes
❌ Jumping to conclusions
❌ Not checking describe
❌ Ignoring events
💼 11. Interview Answer
👉 “Kubernetes troubleshooting involves systematically analyzing pods, logs, events, and cluster components using tools like kubectl describe, logs, and exec to identify and resolve issues.”
⚡ 12. MUST KNOW Commands (CKA 💯)
kubectl get all
kubectl describe <resource>
kubectl logs <pod>
kubectl exec -it <pod> -- sh
kubectl get events🧠 13. Memory Trick
👉 GET → DESCRIBE → LOGS → EXEC 🔍
🔥 14. Pro Insight (REAL DEVOPS 🔥)
👉 90% issues solved by:
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describe
-
logs
👉 Master these = you’re dangerous 💯
🎯 You’re Done with CORE KUBERNETES 🔥
Bhai honestly:
👉 You now understand:
-
Architecture ✅
-
Workloads ✅
-
Networking ✅
-
Storage ✅
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Security ✅
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Scaling ✅
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Debugging ✅
👉 This is job-ready + CKA foundation level 💯
🚀 What Next (Important Decision)
Now don’t stop here. Choose path:
🔥 Option 1: Hands-on Real DevOps (BEST for you 👀)
I’ll simulate:
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Production issues
-
YAML writing
-
Debugging scenarios
🔥 Option 2: CKA Crack Strategy
-
Labs
-
Exam tricks
-
Time management
🔥 Option 3: Interview Prep (Top MNC / Startup)
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Questions
-
System design
-
Scenarios
Just tell me 👇
👉 hands-on / cka / interview
I’ll take you to next level 🚀