Cloud Engineer (AWS) interview questions & mock practice
A Cloud Engineer (AWS) interview in 2026 runs across 4 rounds — aws fundamentals, networking & security, architecture round, scenario / troubleshooting. Below are the most-asked Cloud Engineer (AWS) interview questions and a focused prep plan. Rehearse every answer with OnJob's free AI mock interview and get instant, specific feedback before the real one.
The Cloud Engineer (AWS) interview process
AWS core services, networking, IAM and architecture — the cloud-engineering interview for cloud-native teams and companies migrating to AWS.
AWS fundamentals
EC2, S3, IAM, VPC and core managed services.
Networking & security
VPCs, subnets, security groups, IAM policies and encryption.
Architecture round
Design a scalable, highly available AWS architecture.
Scenario / troubleshooting
Cost optimisation and debugging a cloud issue.
Most-asked Cloud Engineer (AWS) interview questions
12 of the questions Cloud Engineer (AWS) candidates are asked most often in India. Practise answering each one out loud in your AI mock interview.
- 1. What is the difference between EC2, Lambda, and ECS/Fargate?
- 2. Explain the difference between S3 storage classes and when you'd use each.
- 3. What is the difference between a security group and a network ACL?
- 4. How does IAM work — explain users, roles, policies and the principle of least privilege?
- 5. What is a VPC, and how do public and private subnets differ?
- 6. Explain the difference between a NAT gateway and an internet gateway.
- 7. How do you design a highly available, fault-tolerant architecture on AWS?
- 8. What is the difference between horizontal and vertical scaling, and how do Auto Scaling groups help?
- 9. Explain the difference between Amazon RDS, DynamoDB and Aurora.
- 10. How do you secure data at rest and in transit on AWS?
- 11. What is CloudFormation / Terraform, and why use infrastructure as code?
- 12. How would you reduce the AWS bill for an over-provisioned environment?
How to prepare for your Cloud Engineer (AWS) interview
Know the core services cold: EC2, S3, IAM, VPC, RDS, Lambda, and load balancers — and when to use each.
Understand networking and security deeply: VPCs, subnets, route tables, security groups, NACLs and IAM policies.
Be able to whiteboard a highly available, multi-AZ architecture and justify your choices.
Learn infrastructure as code (Terraform or CloudFormation) and basic cost-optimisation levers.
Consider an AWS certification (Solutions Architect Associate) — many roles screen for it.
Practise other roles
- Software Engineer
- Frontend Developer
- Backend Developer
- Full Stack Developer
- Data Analyst
- Data Scientist
- Product Manager
- DevOps Engineer
- Java Developer
- Python Developer
- UI/UX Designer
- Sales / Business Development
- Digital Marketing
- HR / Recruiter
- Accountant
- Customer Support
- Data Engineer
- Machine Learning Engineer
- QA / Test Engineer
- Android Developer
- iOS Developer
- Business Analyst
- Project Manager
- Scrum Master
- SQL Developer
- React Developer
- Node.js Developer
- Cybersecurity Analyst
- Network Engineer
- Database Administrator
- SEO Specialist
- Content Writer
- Graphic Designer
- Sales Executive
- Business Development Manager
- Operations Manager
- Financial Analyst
- Chartered Accountant
- Customer Success Manager
- Technical Support Engineer
- Civil Engineer
Interview prep guides
Cloud Engineer (AWS) interview — FAQs
What questions are asked in a Cloud Engineer (AWS) interview?
Common Cloud Engineer (AWS) interview questions include: What is the difference between EC2, Lambda, and ECS/Fargate? Explain the difference between S3 storage classes and when you'd use each. What is the difference between a security group and a network ACL? How does IAM work — explain users, roles, policies and the principle of least privilege? Interviews usually run across 4 rounds — AWS fundamentals, Networking & security, Architecture round, Scenario / troubleshooting. Practice all of them with instant AI feedback using OnJob's free mock interview.
How many rounds are in a Cloud Engineer (AWS) interview?
A typical Cloud Engineer (AWS) interview has 4 rounds: AWS fundamentals (EC2, S3, IAM, VPC and core managed services.); Networking & security (VPCs, subnets, security groups, IAM policies and encryption.); Architecture round (Design a scalable, highly available AWS architecture.); Scenario / troubleshooting (Cost optimisation and debugging a cloud issue.).
How do I prepare for a Cloud Engineer (AWS) interview?
To prepare for a Cloud Engineer (AWS) interview: Know the core services cold: EC2, S3, IAM, VPC, RDS, Lambda, and load balancers — and when to use each. Understand networking and security deeply: VPCs, subnets, route tables, security groups, NACLs and IAM policies. Be able to whiteboard a highly available, multi-AZ architecture and justify your choices. Then run a full AI mock interview on OnJob to rehearse out loud and get instant, specific feedback before the real thing.
What skills do I need for a Cloud Engineer (AWS) role?
Core Cloud Engineer (AWS) skills tested in interviews include AWS, EC2 / S3, IAM, VPC, Terraform, Lambda, Cloud Architecture. OnJob shows you exactly which of these skills stand between you and a 100% match on every live Cloud Engineer (AWS) job.
Is OnJob's Cloud Engineer (AWS) mock interview free?
Yes. OnJob's AI mock interview is free to start (₹0) and gives you instant feedback on your answers. Pro (₹99/month) adds unlimited interview-prep AI alongside recruiter tracking and unlimited applications.
Ace your Cloud Engineer (AWS) interview
Rehearse every Cloud Engineer (AWS) question out loud with OnJob's AI mock interview and get instant, specific feedback. Then apply to AI-matched jobs in one click — free to start.
Everything about Cloud Engineer (AWS) on OnJob
Move across the whole Cloud Engineer (AWS) topic — live openings, real salary data, the job description, interview prep, and early-career routes — all in one place.