Practice Amazon Web Services questions covering EC2, S3, Lambda, IAM, VPC, and cloud architecture best practices.
Core services include EC2, S3, Lambda, IAM, VPC, RDS, DynamoDB, SQS, SNS, CloudFront, and Route 53. For DevOps roles, also know CloudFormation/CDK, CodePipeline, ECS/EKS, and CloudWatch. Understanding the Well-Architected Framework is valuable.
AWS interviews focus on specific service selection and configuration, IAM policies, VPC networking, and cost optimization. They test your ability to choose the right AWS service for specific requirements and understand service limits and pricing models.
EC2 provides virtual servers you manage yourself. Lambda is serverless - you upload code and AWS handles scaling and infrastructure. ECS/EKS runs Docker containers with orchestration. Choose EC2 for full control, Lambda for event-driven short tasks, and ECS for containerized applications.
IAM controls who can access what in AWS. It uses users, groups, roles, and policies. Policies are JSON documents defining permissions. Best practices include least privilege, using roles over access keys, enabling MFA, and using service-linked roles for cross-service access.
It consists of six pillars: Operational Excellence, Security, Reliability, Performance Efficiency, Cost Optimization, and Sustainability. Each pillar provides best practices for building robust cloud architectures. Interviewers often frame questions around these pillars.
Use multiple Availability Zones for redundancy, Auto Scaling Groups for EC2, multi-AZ RDS deployments, S3 for durable storage, Route 53 health checks for DNS failover, and CloudFront for global content delivery. Design every component to handle the failure of any single AZ.