AWS DevOps Interview Questions
Top AWS DevOps interview questions and answers covering CodePipeline, CodeBuild, CodeDeploy, CloudFormation, ECS, EKS, GitOps, CI/CD, DevSecOps, Monitoring, IAM, and production AWS architectures.
Introduction
AWS DevOps interviews focus on your understanding of cloud-native CI/CD, automation, Infrastructure as Code (IaC), monitoring, security, Kubernetes deployments, and troubleshooting production systems.
Interviewers typically expect you to explain not only AWS services but also how they work together in a real-world DevOps pipeline.
This guide covers beginner to advanced interview questions commonly asked for:
- AWS DevOps Engineer
- Cloud Engineer
- Platform Engineer
- SRE
- Solution Architect
- Java Backend Developer
Enterprise AWS DevOps Architecture
flowchart LR
Developer --> GitHub --> CodePipeline --> CodeBuild --> SecurityScan --> AmazonECR --> AmazonEKS --> CloudWatch --> SNS
CI/CD Questions
1. What is AWS DevOps?
Answer
AWS DevOps is the practice of automating software development, testing, infrastructure provisioning, deployment, monitoring, and operations using AWS managed services.
Key goals
- Faster Releases
- Automation
- Reliability
- Scalability
- Security
2. Which AWS services are commonly used in DevOps?
| Service | Purpose |
|---|---|
| CodeCommit | Source Repository |
| CodeBuild | Build |
| CodeDeploy | Deployment |
| CodePipeline | CI/CD |
| CodeArtifact | Package Repository |
| CloudFormation | Infrastructure as Code |
| ECR | Docker Images |
| ECS | Containers |
| EKS | Kubernetes |
| CloudWatch | Monitoring |
3. Explain AWS CodePipeline.
CodePipeline automates software delivery.
Pipeline
flowchart LR
Source --> Build --> Test --> Approval --> Deploy
4. What are CodePipeline stages?
Typical stages
- Source
- Build
- Test
- Security Scan
- Approval
- Deploy
- Monitor
5. Difference between Jenkins and CodePipeline?
| Jenkins | CodePipeline |
|---|---|
| Self Managed | Fully Managed |
| Plugin Based | AWS Native |
| Highly Flexible | AWS Focused |
| Maintenance Required | No Server Maintenance |
CodeBuild Questions
6. What is AWS CodeBuild?
Fully managed build service.
Responsibilities
- Compile Code
- Execute Tests
- Build Docker Images
- Generate Artifacts
7. What is buildspec.yml?
Defines build commands.
Example
version: 0.2
phases:
install:
commands:
- mvn clean
build:
commands:
- mvn package
8. Which environments does CodeBuild support?
- Java
- Python
- Node.js
- Go
- Docker
- .NET
CodeDeploy Questions
9. What is AWS CodeDeploy?
Automates application deployment.
Supports
- EC2
- ECS
- Lambda
- On-Premises Servers
10. Deployment strategies supported?
- In-place Deployment
- Blue-Green Deployment
- Canary Deployment (Lambda/ECS)
- Linear Deployment
- Rolling Updates
CloudFormation Questions
11. What is CloudFormation?
Infrastructure as Code service.
Infrastructure defined using
- YAML
- JSON
Benefits
- Version Control
- Repeatability
- Automation
12. Why use CloudFormation instead of Console?
Advantages
- Repeatable Infrastructure
- Version Controlled
- Easy Rollback
- Disaster Recovery
- Automation
ECR Questions
13. What is Amazon ECR?
Elastic Container Registry stores Docker images.
Benefits
- Secure
- Private
- Versioned
- IAM Integrated
ECS & EKS Questions
14. Difference between ECS and EKS?
| ECS | EKS |
|---|---|
| AWS Native | Kubernetes |
| Easier | More Flexible |
| Less Management | CNCF Standard |
15. CI/CD pipeline for EKS?
flowchart LR
Developer --> GitHub --> CodeBuild --> Docker --> AmazonECR --> ArgoCD --> AmazonEKS
Security Questions
16. How do you secure AWS DevOps pipelines?
Best Practices
- IAM Roles
- Least Privilege
- MFA
- Secrets Manager
- KMS Encryption
- Code Signing
- Security Scanning
17. Where should secrets be stored?
Never in Git.
Use
- AWS Secrets Manager
- Parameter Store
- IAM Roles
Monitoring Questions
18. Which AWS services monitor deployments?
- CloudWatch
- CloudTrail
- X-Ray
- AWS Config
19. Difference between CloudWatch and CloudTrail?
| CloudWatch | CloudTrail |
|---|---|
| Metrics | API Logs |
| Alarms | Audit |
| Dashboards | Security |
GitOps Questions
20. What is GitOps?
Git is the source of truth.
flowchart LR
Git --> ArgoCD --> AmazonEKS
Benefits
- Rollback
- Version Control
- Drift Detection
Deployment Questions
21. Explain Blue-Green Deployment.
flowchart LR
Users --> LoadBalancer
LoadBalancer --> Blue
LoadBalancer --> Green
Traffic switches after validation.
22. Explain Canary Deployment.
flowchart LR
Users --> 5Percent --> NewVersion
Users --> 95Percent --> OldVersion
Deploy to a small percentage of users before full rollout.
DevSecOps Questions
23. What is DevSecOps?
Security integrated into CI/CD.
Pipeline
flowchart LR
Build --> StaticAnalysis --> DependencyScan --> ContainerScan --> Deploy
24. Which security scans should run?
- SAST
- Dependency Scan
- Secret Scan
- Container Scan
- License Scan
Scenario Questions
25. Deployment failed. What would you do?
Steps
- Stop deployment
- Review logs
- Verify infrastructure
- Rollback
- Fix issue
- Redeploy
26. Build works locally but fails in CodeBuild.
Possible reasons
- Missing Environment Variables
- Java Version
- IAM Permissions
- Network
- Dependencies
27. CodePipeline stopped at Build stage.
How do you troubleshoot?
Check
- Build Logs
- buildspec.yml
- IAM Role
- Source Artifact
- Environment Variables
28. CloudFormation stack failed.
What should you verify?
- Template Syntax
- Resource Limits
- IAM Permissions
- Existing Resources
- Rollback Events
29. Production deployment increased error rate.
Steps
- CloudWatch Metrics
- Logs
- X-Ray
- Rollback
- Root Cause Analysis
30. ECS deployment keeps failing health checks.
Possible causes
- Wrong Health Check Path
- Container Crash
- Port Mapping
- Security Groups
- Target Group Configuration
Advanced Questions
31. Why use Multi-Account AWS?
Benefits
- Security
- Billing Isolation
- Compliance
- Environment Separation
32. Explain Cross-Account Deployment.
flowchart LR
CodePipeline --> STSAssumeRole --> ProductionAccount --> Deploy
33. What is immutable infrastructure?
Never modify running servers.
Instead
Create New Infrastructure
↓
Deploy
↓
Switch Traffic
↓
Delete Old Infrastructure
34. Explain Infrastructure as Code.
Provision infrastructure using code.
Examples
- CloudFormation
- Terraform
- AWS CDK
35. Why should artifacts never be rebuilt?
Rebuilding changes binaries.
Always deploy the same tested artifact.
Production Best Practices
- Infrastructure as Code
- Immutable Deployments
- Blue-Green Releases
- Canary Deployments
- Automatic Rollback
- Automated Testing
- Security Scanning
- Secrets Manager
- CloudWatch Monitoring
- Least Privilege IAM
Common AWS DevOps Services
| Category | Service |
|---|---|
| Source | CodeCommit |
| CI/CD | CodePipeline |
| Build | CodeBuild |
| Deployment | CodeDeploy |
| Artifacts | CodeArtifact |
| Registry | Amazon ECR |
| Containers | Amazon ECS |
| Kubernetes | Amazon EKS |
| Infrastructure | CloudFormation |
| Infrastructure Code | AWS CDK |
| Monitoring | CloudWatch |
| Audit | CloudTrail |
| Secrets | Secrets Manager |
Quick Revision Cheat Sheet
| Topic | Key Point |
|---|---|
| CodeCommit | Git Repository |
| CodePipeline | CI/CD |
| CodeBuild | Build Service |
| CodeDeploy | Deployment |
| ECR | Docker Registry |
| ECS | Container Service |
| EKS | Kubernetes |
| CloudFormation | IaC |
| CloudWatch | Monitoring |
| CloudTrail | Audit |
| Secrets Manager | Secret Storage |
| IAM | Authentication & Authorization |
| Blue-Green | Zero Downtime |
| Canary | Progressive Rollout |
| GitOps | Git as Source of Truth |
Real-World Production Scenario
flowchart LR
Developer --> GitHub --> CodePipeline --> CodeBuild --> SonarQube --> Trivy --> DockerBuild --> AmazonECR --> Approval --> AmazonEKS --> CloudWatch --> SNSAlerts
CloudWatch -- Failure --> Rollback
A developer commits code to GitHub. CodePipeline triggers automatically, CodeBuild compiles and tests the application, SonarQube performs static code analysis, Trivy scans the Docker image, and the image is pushed to Amazon ECR. After approval, Amazon EKS performs a Blue-Green deployment. CloudWatch continuously monitors health metrics. If error rates exceed the defined threshold, the deployment is automatically rolled back, and SNS notifies the operations team.
Summary
AWS DevOps interviews focus on practical knowledge of CI/CD automation, Infrastructure as Code, container orchestration, deployment strategies, security, monitoring, and production troubleshooting.
Understanding how AWS services work together to build secure, scalable, and highly available delivery pipelines is essential for DevOps Engineer, Cloud Engineer, Platform Engineer, SRE, and Solution Architect roles.
Practice these scenarios along with hands-on implementation using CodePipeline, CodeBuild, CodeDeploy, CloudFormation, EKS, ECS, and CloudWatch to confidently handle real-world interviews.