πŸ’₯Crack the Code: 20 Must-Know Cloud DevOps Scenario-Based Interview Questions

Hi Inner Circle,



πŸ” Why Are Scenario-Based Questions So Important?


These are real-world curveballs.

Picture this:

* Your Kubernetes deployment is failing.







So, why are these questions crucial?

βœ… They test your troubleshooting under pressure

βœ… They reflect real production complexity

🎯 Let’s Dive Into Part 1: 20 DevOps Scenarios You Must Master
1.Β Diagnosing High Latency in Cloud-Native Apps
* Check Grafana, Prometheus, or Cloud Monitoring dashboards

* Analyze API Gateway and Load Balancer latency


πŸ’‘ Tip: Start with metrics β†’ logs β†’ code

2.Β Kubernetes Pod in CrashLoopBackOff

* Inspect resource limits or init container status

3.Β CI/CD Pipeline Is Broken
* Check Jenkins/GitHub Actions logs

* Validate pipeline YAML, env vars, and secrets

* Run steps locally before pushing

4.Β Securing Public Cloud Storage Buckets
* Disable public access (via AWS/GCP/Azure settings)

* Enforce encryption (SSE-S3 or SSE-KMS)

* Use IAM policies and CloudTrail auditing
πŸ’‘ Tip: Never skip logging

5.Β Terraform Apply Fails in Cloud Infra
* Run terraform validate and plan

* Use remote state, modules, and workspaces

6.Β Debugging Failed Kubernetes Deployments
* Use kubectl rollout status and describe deployment

* Investigate logs for ImagePullBackOff or env issues


πŸ’‘ Tip: Start with deployment history and logs

7.Β Cloud Cost Spike?Β Here’s What To Do

* Identify idle resources or unused IPs/volumes


πŸ’‘ Tip: Auto-stop dev/test workloads out of hours

8.Β Blue-Green Deployment Failures
* Validate readiness probes and version health

* Check traffic routing or DNS misconfigs

* Revert switch or automate rollback (Argo Rollouts)
πŸ’‘ Tip: Canary might be safer for smaller releases

9.Β IAM Access Denied Issues
* Read the error message carefully

* Test policies via IAM Policy Simulator

* Ensure correct role/assume-role setup
πŸ’‘ Tip: Follow Least Privilege principleβ€”always

10.Β Kubernetes Internal Service Communication Failure
* Use nslookup and curl inside pods

* Validate ClusterIP service setup

* Check NetworkPolicies and CNI plugins

πŸ” Advanced DevOps Scenarios

11.Β Monitoring Microservices
* Scrape with Prometheus, visualize in Grafana

* Add distributed tracing (OpenTelemetry)

* Use centralized logging (ELK/Loki)
πŸ’‘ Tip: Define SLIs and dashboards per service

12.Β Kubernetes Security Best Practices
* Apply RBAC and restrict service accounts

* Use NetworkPolicies and PodSecurityStandards

* Scan images (Trivy, Clair)
πŸ’‘ Tip: Run kubectl auth can-i for audits

13.Β Handling Sudden Traffic Spikes
* Enable HPA and Cluster Autoscaler

* Add Redis, CDN, and offload static content

* Use Load Balancers and proper resource limits
πŸ’‘ Tip: Monitor limits to avoid OOM kills

14.Β Secure Container Debugging
* Restrict kubectl exec via RBAC

* Use ephemeral debug containers

* Enable exec/audit logs
πŸ’‘ Tip: Use session-based access for sensitive clusters

15.Β Container Won’t Start?
* Run docker logs or kubectl logs

* Check image tags, volumes, and permissions

* Review Dockerfile CMD/ENTRYPOINT
πŸ’‘ Tip: Always test locally with docker run first

16.Β Blue-Green vs. Canary – When to Use What?
* Blue-green = full shift with instant rollback

* Canary = gradual rollout with metric validation

* Automate with ArgoCD or Flagger
πŸ’‘ Tip: Risk level should guide your decision

17.Β Kubernetes Memory Leak

* Restart services and enable profiling

* Setup memory usage alerts
πŸ’‘ Tip: Include leak checks in CI pipeline

18.Β Safe Production DB Migrations
* Always backup

* Use versioned migration tools (Flyway, Liquibase)

* Test rollback scripts
πŸ’‘ Tip: Use feature flags for gradual schema rollout

19.Β Misconfigured Ingress Controller
* Use kubectl describe ingress for error clues

* Validate host/path rules and backend services

* Check NGINX/Traefik-specific annotations
πŸ’‘ Tip: Wrong TLS configs are common

20.Β Building High Availability Architectures
* Use Multi-AZ for compute and databases

* Add Load Balancers, Auto Scaling, DNS failover

* Refer to AWS Well-Architected Framework
πŸ’‘ Tip: Monitor RTO/RPO and set SLAs

🧠 Final Words (For Now…)

* CI/CD optimizations

* Kubernetes chaos scenarios

* Cloud security breaches

* And much more…

Made for you,
By Ravi Shanker Singh
πŸ‘¨β€πŸ’»

Kubernetes Ingress Deep Dive: The Smart Gateway for Your Cluster

πŸšͺ What is Kubernetes Ingress?

Think of it like this:

βš™οΈ What is an Ingress Controller?

πŸ” How Ingress Works (Step-by-Step)

Client Request
A user sends a request to https://app.example.com/login.

DNS Resolution

Ingress Controller Listens

Ingress Rules Evaluated

Traffic Routed to Service

Response Returned

Simple, smart, and centralized.Β βœ…

πŸ› οΈ Why Use Ingress in Kubernetes?
Ingress changes the game:

🎯 Centralized Routing: One place to manage all external access.

πŸ”’ TLS/SSL Termination: Handle HTTPS from a single point.

🚦 When Should You Use Ingress?
Use Ingress when:

πŸ‘ Advantages of Using Ingress Feature Benefit



βœ… Cost Efficiency One LoadBalancer for all
βœ… Declarative Config GitOps-friendly with YAML

⚠️ Disadvantages of Using Ingress

πŸ“š Learning Curve – Not beginner-friendly, especially with TLS.

But for most web applications and microservices?Β Ingress is worth the effort.

🌐 Real-World Example: Before vs After Ingress
Without Ingress

Each needs its own TLS/SSL config.

Difficult to maintain, expensive to scale.

With Ingress

One external IP.

One place to manage SSL certs.

Cleaner, cheaper, faster.

🧠 Final Thoughts

ControllerHighlights
NGINXMost popular, stable, and highly customizable
TraefikLightweight, supports dynamic routing, metrics built-in
HAProxyHigh-performance with advanced capabilities
Istio GatewayFor service mesh scenarios
AWS ALB IngressBest for AWS environments
GKE IngressOptimized for Google Cloud
ContourLightweight and fast with Envoy

Sample Ingress YAML

Here’s what a basic Ingress configuration looks like:

“apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
name: my-ingress
annotations:
nginx.ingress.kubernetes.io/rewrite-target: /
spec:
rules:
– host: app.example.com
http:
paths:
– path: /login
pathType: Prefix
backend:
service:
name: auth-service
port:
number: 80
– path: /dashboard
pathType: Prefix
backend:
service:
name: dashboard-service
port:
number: 80

Download the full PDF.Kubernetes Ingress Deep Dive