1. What is DevOps in AWS?
DevOps in AWS combines development and operations using AWS services to automate infrastructure, CI/CD, monitoring, and scaling. It focuses on Infrastructure as Code, automation, continuous delivery, and high availability.
2. How have you implemented CI/CD in AWS?
I implemented CI/CD using AWS CodePipeline integrated with AWS CodeBuild and AWS CodeDeploy. The pipeline automatically triggered on Git commits and deployed applications to EC2 and ECS environments.
3. What is Infrastructure as Code and how did you use it?
Infrastructure as Code allows provisioning infrastructure using code instead of manual setup. I used AWS CloudFormation and Terraform to automate VPCs, EC2, IAM roles, and load balancers.
4. How do you manage environments (Dev, QA, Prod)?
I create separate AWS accounts using AWS Organizations for strong isolation. Each environment has its own VPC, IAM policies, and CI/CD pipeline with approval gates for production.
5. How do you handle zero-downtime deployments?
I use blue-green deployments via CodeDeploy or rolling updates in Auto Scaling groups. This ensures traffic shifts gradually and allows rollback if health checks fail.
6. What is your experience with containerization in AWS?
I containerized applications using Docker and deployed them on Amazon ECS and Amazon EKS. This improved portability, scalability, and simplified deployment pipelines.
7. How do you monitor applications in AWS?
I use Amazon CloudWatch for logs, metrics, and alarms. Additionally, I configure dashboards and SNS alerts for proactive monitoring.
8. How do you secure CI/CD pipelines?
I use IAM roles with least privilege access and encrypt artifacts using KMS. Secrets are stored in AWS Secrets Manager and never hardcoded in repositories.
9. Explain how Auto Scaling works.
Auto Scaling automatically adjusts EC2 capacity based on metrics like CPU or memory. It ensures high availability and cost optimization during traffic spikes.
10. How do you manage secrets in AWS?
I store credentials in AWS Secrets Manager or Parameter Store. Applications retrieve secrets dynamically at runtime to enhance security.
11. What is a VPC and how have you designed one?
A VPC is an isolated virtual network in AWS. I designed multi-tier architectures with public subnets for ALB and private subnets for EC2 and databases.
12. How do you ensure high availability?
I deploy resources across multiple Availability Zones. Load balancers distribute traffic, and Auto Scaling maintains instance health.
13. What is blue-green deployment?
It involves running two identical environments (blue and green). Traffic switches to the new version only after validation.
14. What is canary deployment?
Canary releases route small traffic to a new version first. If no issues are found, traffic gradually increases.
15. How do you optimize AWS costs?
I use Reserved Instances and Savings Plans for predictable workloads. Spot Instances are used for non-critical batch jobs.
16. What is an Application Load Balancer?
An ALB distributes HTTP/HTTPS traffic to multiple targets. It supports path-based routing and microservices architectures.
17. How do you troubleshoot high CPU on EC2?
I check CloudWatch metrics and logs to identify the root cause. Then I scale out or optimize application performance.
18. What is IAM?
IAM controls access to AWS resources. I create roles, policies, and enforce least privilege principles.
19. How do you manage logs?
Logs are centralized in CloudWatch Logs. I also export them to S3 for long-term retention.
20. How do you automate backups?
I configure AWS Backup policies for EC2 and RDS. Snapshots are scheduled and retained based on compliance requirements.
21. What is RDS Multi-AZ?
Multi-AZ provides high availability by replicating the database to a standby instance. Failover happens automatically if the primary fails.
22. How do you implement disaster recovery?
I design DR strategies like pilot light or warm standby. Cross-region replication ensures minimal downtime.
23. What is S3 lifecycle policy?
Lifecycle policies automatically transition objects between storage classes. It reduces cost by moving old data to Glacier.
24. What is a security group?
A security group acts as a virtual firewall for EC2 instances. It controls inbound and outbound traffic.
25. How do you deploy microservices?
I use containers and deploy them on ECS or EKS. Each service runs independently behind an ALB.
26. What is CodeBuild?
CodeBuild compiles source code and runs tests automatically. It scales automatically without managing servers.
27. What is CodeDeploy?
CodeDeploy automates application deployment to EC2, Lambda, or ECS. It supports blue-green and in-place deployments.
28. What is Lambda in DevOps?
Lambda runs code without provisioning servers. It is useful for event-driven automation tasks.
29. What is SNS?
SNS is a messaging service for sending alerts and notifications. It integrates with email, SMS, and Lambda.
30. What is SQS?
SQS is a fully managed message queue service. It decouples microservices and improves reliability.
31. How do you handle configuration management?
I use Systems Manager Parameter Store. Infrastructure variables are managed through Terraform or CloudFormation.
32. What is CloudTrail?
CloudTrail logs all API activity in AWS. It helps in auditing and security investigations.
33. What is a NAT Gateway?
A NAT Gateway allows private instances to access the internet securely. It prevents inbound internet traffic to private subnets.
34. How do you implement rolling updates?
Rolling updates replace instances gradually. This ensures continuous availability.
35. How do you handle failed deployments?
I enable automatic rollback in CodeDeploy. Monitoring alarms trigger rollback if thresholds are breached.
36. What is ECR?
ECR stores Docker container images securely. It integrates with ECS and EKS.
37. How do you manage multi-account strategy?
I use AWS Organizations for account governance. Service Control Policies enforce compliance rules.
38. What is Route 53?
Route 53 is AWS DNS service. It supports health checks and traffic routing policies.
39. How do you secure S3?
I block public access and use bucket policies. Data is encrypted at rest and in transit.
40. What is Elastic Beanstalk?
Elastic Beanstalk automates application deployment. It provisions EC2, load balancers, and scaling automatically.
41. How do you implement DevSecOps?
Security checks are integrated into CI/CD pipelines. Static code analysis and vulnerability scans run before deployment.
42. What is a launch template?
Launch templates define EC2 instance configurations. They are used in Auto Scaling groups.
43. What is a target group?
Target groups route traffic from load balancers to instances. Health checks determine traffic routing.
44. What is KMS?
KMS manages encryption keys securely. It is used for encrypting EBS, S3, and RDS.
45. What is parameter store?
Parameter Store stores configuration data securely. It supports encrypted and plain text parameters.
46. How do you scale Kubernetes in AWS?
I use cluster autoscaler in EKS. Worker nodes scale based on pod requirements.
47. What is CloudFront?
CloudFront is a CDN service. It improves performance by caching content globally.
48. How do you handle log retention?
I configure retention policies in CloudWatch. Older logs are archived in S3.
49. What is a bastion host?
A bastion host provides secure SSH access to private instances. It resides in a public subnet.
50. Describe a real DevOps project you handled.
I built a CI/CD pipeline deploying containerized applications to EKS. The setup improved deployment speed by 60% and reduced downtime to zero using blue-green strategy.
Conclusion
Preparing for AWS DevOps interviews requires more than memorizing services it demands real project understanding, automation mindset, and hands-on troubleshooting experience. Interviewers typically evaluate how well you design scalable architectures, implement CI/CD pipelines, secure infrastructure, and handle production incidents using core services from Amazon Web Services.
The 50 real project-based questions covered in this guide focus on practical experience with tools like AWS CodePipeline, AWS CloudFormation, Amazon EKS, and Amazon CloudWatch which are commonly discussed in DevOps interviews.
To stand out:
- Explain real production challenges you solved
- Emphasize automation and Infrastructure as Code
- Highlight cost optimization and security best practices
- Demonstrate incident handling and rollback strategies
Consistent hands-on practice, building real pipelines, and designing high-availability architectures will significantly improve your confidence. Focus on explaining why you chose a solution, not just what service you used that’s what truly differentiates experienced AWS DevOps engineers.
