DevOps Engineer Interview FAQs: Most Asked Questions in 2026

# Sample GitHub Actions pipeline (CI/CD)
name: build-and-deploy

on:
  push:
    branches: [ main ]

jobs:
  build:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - name: Set up Docker
        uses: docker/setup-buildx-action@v3
      - name: Run tests
        run: |
          docker build -t app:test .
          docker run --rm app:test pytest
      - name: Build & push image
        run: |
          docker build -t app:${{ github.sha }} .
          echo "${{ secrets.REGISTRY_PASS }}" | docker login -u "${{ secrets.REGISTRY_USER }}" --password-stdin
          docker tag app:${{ github.sha }} registry.example.com/app:${{ github.sha }}
          docker push registry.example.com/app:${{ github.sha }}

  deploy:
    needs: build
    runs-on: ubuntu-latest
    steps:
      - name: Deploy via Helm
        run: |
          helm upgrade --install app ./chart \
            --set image.tag=${{ github.sha }}

Pipeline review checklist:
□ Tests run before image build?
□ Image tagged with commit SHA?
□ Secrets stored in a vault, not the repo?
□ Deployment separated from build?
□ Rollback path defined?
□ Notifications on failure?
□ Pipeline runs under 15 minutes?

# Debug a failing pod
kubectl get pods
kubectl describe pod <name>
kubectl logs <name> --previous
kubectl get events --sort-by=.metadata.creationTimestamp
kubectl exec -it <name> -- sh

# Check resources
kubectl top pods
kubectl describe node <node>

How to answer "CrashLoopBackOff":

"First, I check logs (including --previous).
Then I run describe to see recent events.
Next I check if resource requests or limits are
too low, or if config maps or secrets are missing.
If it's a network issue, I check DNS and readiness
probes. If it's a startup error, I exec into the pod
or use an init container to debug."

# Example Prometheus alert rule
groups:
  - name: app-alerts
    rules:
      - alert: HighErrorRate
        expr: sum(rate(http_requests_total{status=~"5.."}[5m]))
              / sum(rate(http_requests_total[5m])) > 0.05
        for: 5m
        labels:
          severity: page
        annotations:
          summary: "Error rate above 5% for 5 minutes"

Incident response checklist:
□ Acknowledge the alert
□ Check dashboards and recent deploys
□ Identify user impact
□ Stabilize (rollback, scale, disable flag)
□ Communicate to stakeholders
□ Fix root cause
□ Write a postmortem
□ Add monitoring to prevent recurrence

Month 1 — Fundamentals:
Week 1 — Linux, networking, DNS, HTTP
Week 2 — Git, GitHub, branching
Week 3 — Docker: images, containers, volumes
Week 4 — CI/CD basics (GitHub Actions or Jenkins)

Daily routine:
9:00 AM — Theory (2 hours)
11:00 AM — Hands-on lab (2 hours)
2:00 PM — Practice questions (1 hour)
5:00 PM — Review & notes (1 hour)

Milestone:
□ Comfortable with Linux commands
□ Dockerized a small app
□ Built a basic pipeline

Month 2 — Deep Skills:
Week 5 — Kubernetes: pods, services, deployments
Week 6 — Helm, Ingress, config maps, secrets
Week 7 — Cloud (AWS): VPC, IAM, EC2, S3, EKS
Week 8 — Monitoring: Prometheus, Grafana, logs

Daily routine:
9:00 AM — Theory (2 hours)
11:00 AM — Hands-on lab (3 hours)
2:00 PM — Debugging exercises (1 hour)
5:00 PM — Documentation (1 hour)

Milestone:
□ Deployed to Kubernetes
□ Set up monitoring alerts
□ Used AWS with least privilege

Month 3 — Interview Practice:
Week 9 — Revisit each FAQ with real examples
Week 10 — Mock interviews
Week 11 — System design and incident stories
Week 12 — Applications and follow-ups

Daily routine:
9:00 AM — Mock interview practice (2 hours)
11:00 AM — Review answers & improve (2 hours)
2:00 PM — Apply and network (1 hour)
5:00 PM — Read postmortems (1 hour)

Milestone:
□ 10+ mock interviews done
□ Clear stories for every FAQ
□ 30+ applications sent

Daily Tracker:
Date: _________
☐ Morning routine completed
☐ DevOps theory (2 hours)
☐ Hands-on lab (2 hours)
☐ Interview Q&A practice (1 hour)
☐ System design study (1 hour)
☐ Exercise completed
☐ Reviewed progress
☐ Planned tomorrow

Today's Accomplishments:
1. 
2. 
3. 

Tomorrow's Priorities:
1. 
2. 
3. 

Weekly Tracker:
Week: _____ (Month 1 / 2 / 3)

Goals for this week:
1. 
2. 
3. 

Daily Progress:
Mon: ☐☐☐
Tue: ☐☐☐
Wed: ☐☐☐
Thu: ☐☐☐
Fri: ☐☐☐
Sat: ☐☐☐
Sun: ☐☐☐

Weekly Wins:
1. 
2. 
3. 

Challenges & Solutions:
1. 
2. 

Next Week's Goals:
1. 
2. 
3. 

Monthly Tracker:
Month: _____ (1 / 2 / 3)

Monthly Goal:
_______________________________________________

Week 1 Progress: ☐☐☐
Week 2 Progress: ☐☐☐
Week 3 Progress: ☐☐☐
Week 4 Progress: ☐☐☐

Monthly Wins:
1. 
2. 
3. 

Skills Gained:
1. 
2. 
3. 

Incident Stories Collected:
1. 
2. 
3. 

Applications Sent: _____
Interviews: _____
Offers: _____

Next Month's Goal:
_______________________________________________