500+ AWS Interview Questions with Answer 2026

Detailed Exam Domain CoverageThis comprehensive practice test bank is systematically mapped to the exact breakdown of domains found in professional AWS technical interviews, architectural reviews, and advanced cloud certifications:Core AWS Services (20%)Topics Covered: Elastic Compute Cloud (EC2) instance types and placement groups, Simple Storage Service (S3) storage classes and lifecycle policies, Virtual Private Cloud (VPC) subnets, Identity and Access Management (IAM) policies, and Relational Database Service (RDS) deployment topographies.Security and Compliance (18%)Topics Covered: IAM cross-account roles, Security Groups stateful inspection, Network Access Control Lists (NACLs) stateless filtering, Route 53 DNSSEC, and CloudWatch security log aggregation.Networking and Connectivity (15%)Topics Covered: VPC Peering limitations, AWS Direct Connect routing options, AWS Site-to-Site VPN failover, Transit Gateway centralized routing architectures, and AWS PrivateLink interface endpoints.Database and Storage (12%)Topics Covered: RDS multi-AZ vs. read replicas, DynamoDB partition keys and global tables, S3 performance optimization, Elastic Block Store (EBS) volume performance characteristics (io2 vs. gp3), and Elastic File System (EFS) mounting.Application Services and Deployment (10%)Topics Covered: Elastic Container Service (ECS) task definitions, Elastic Kubernetes Service (EKS) networking, AWS Lambda execution contexts and concurrency limits, API Gateway integrations, and CloudFormation infrastructure-as-code parameterization.Monitoring and Troubleshooting (8%)Topics Covered: CloudWatch alarms and metric filters, CloudTrail API auditing, AWS X-Ray distributed tracing, and CloudFormation drift detection remediation workflows.Cost Optimization and Management (7%)Topics Covered: AWS Cost Explorer analysis, Trusted Advisor optimization checks, Savings Plans vs. Reserved Instances, Spot Instances termination handling, and Auto Scaling group allocation strategies.Architecture and Design (10%)Topics Covered: AWS Well-Architected Framework pillars, designing for high availability and durability, decoupling monolithic workloads for scalability, and multi-region Disaster Recovery (DR) strategies (Pilot Light, Warm Standby).Course DescriptionSucceeding in an AWS cloud engineering or architectural interview requires much more than a superficial understanding of service names. Technical interviewers look for engineers who understand deep architectural trade-offs, security implications, network isolation patterns, and cost boundaries. I built this targeted practice test bank to serve as a rigorous, scenario-based study material that directly replicates the problem-solving environments you will encounter during live technical interview loops.With a massive library of highly detailed, scenario-focused questions, this course shifts your focus away from basic memorization toward true architectural logic. You will navigate complex operational challenges involving overlapping IP ranges, database replication lag, strict data perimeter security, and erratic application traffic spikes.Every single question includes an exhaustive explanation that clarifies the cloud mechanics behind the right answer while breaking down why the five alternative choices fail under real-world conditions. By working through these practical scenarios, you will build the system-design instincts needed to pass technical screenings on your first attempt and confidently justify your engineering decisions to senior panel interviewers.Sample Practice Questions PreviewQuestion 1: Networking and ConnectivityYour company needs to establish a secure, private connection between its corporate VPC and a third-party vendor's analytics application hosted in a separate AWS account. The corporate infrastructure team mandates that traffic must never traverse the public internet. Furthermore, the vendor's VPC uses an overlapping CIDR block ($10.0.0.0/16$) with your corporate VPC. Which architectural approach satisfies these security and routing requirements?A) Establish a standard VPC Peering connection between your VPC and the vendor's VPC, then update the respective route tables.Why Incorrect: VPC Peering strictly requires non-overlapping CIDR blocks. Because both VPCs use the $10.0.0.0/16$ range, a peering connection cannot be initialized or routed correctly.B) Deploy an internet-facing Network Load Balancer (NLB) in the vendor account and route traffic via an AWS Site-to-Site VPN over the public internet.Why Incorrect: This architecture violates the core security mandate that traffic must never traverse the public internet, even if encrypted via VPN, and introduces unnecessary exposure through the internet-facing NLB.C) Provision an AWS Direct Connect connection dedicated solely to the vendor's account and configure a Private Virtual Interface (VIF).Why Incorrect: AWS Direct Connect is designed to connect on-premises data centers to AWS environments. It does not natively resolve inter-VPC account connections with overlapping subnets without complex, costly on-premises routing hairpins.D) Instruct the vendor to create an AWS PrivateLink endpoint service powered by a Network Load Balancer, and provision an Interface VPC Endpoint in your corporate VPC.Why Correct: AWS PrivateLink allows you to privately connect your VPC to supported services without traversing the internet. Because it operates by placing an Elastic Network Interface (ENI) with a specific private IP within your own subnet, it completely bypasses the limitations of overlapping VPC-level CIDR blocks and eliminates internet exposure.E) Connect both VPCs to a centralized AWS Transit Gateway (TGW) and isolate them using distinct TGW Route Tables.Why Incorrect: While Transit Gateway simplifies multi-VPC networking, attaching two VPCs with identical, overlapping CIDR blocks to the same TGW still causes IP routing conflicts if those VPCs need to communicate directly with one another.F) Set up an AWS Client VPN endpoint within your VPC and configure the vendor's backend systems to authenticate as external client nodes.Why Incorrect: Client VPN is designed for remote users connecting securely to an AWS environment from their local devices. It is not an enterprise-grade, architecture-compliant mechanism for machine-to-machine VPC service integration.Question 2: Database and StorageA critical transactional e-commerce system requires a highly available, relational database architecture. The system must support low-latency reads ( 1 second) for read-heavy microservices deployed across primary regions in North America and secondary regions in Europe. In the event of a total primary region failure, the recovery point objective (RPO) must be under 1 minute and the recovery time objective (RTO) must be under 15 minutes. Which database engine configuration natively meets these requirements with the lowest operational overhead?A) Deploy a standard Amazon RDS PostgreSQL instance with cross-region read replicas configured in Europe.Why Incorrect: Standard RDS cross-region read replicas use asynchronous engine-level replication which can experience significant lag under high load, risking the 1-minute RPO. Additionally, promoting an RDS replica to a primary instance requires manual intervention or complex custom scripting, making it difficult to guarantee a strict 15-minute RTO during a disaster.B) Provision an Amazon Aurora Global Database with the primary cluster in North America and a secondary cluster in Europe, utilizing managed planned failovers.Why Correct: Amazon Aurora Global Database uses dedicated storage-based replication that operates independently of the database engine compute layer, typically achieving replication lag of less than 1 second. It supports quick cross-region failovers that can be executed within minutes (meeting the 15-minute RTO) with zero data loss under managed conditions, fully satisfying the 1-minute RPO.C) Implement Amazon DynamoDB with Global Tables enabled across both North America and Europe regions.Why Incorrect: DynamoDB is a NoSQL key-value database. The application requirements explicitly state a need for a relational database architecture to preserve strict SQL transactional guarantees and schemas.D) Use an Amazon RDS Multi-AZ deployment across three Availability Zones within the primary North America region.Why Incorrect: Multi-AZ deployments provide synchronous replication and high availability within a single region. They do not provide low-latency local reads or disaster recovery capabilities for users located in the Europe region.E) Configure Amazon ElastiCache for Redis with a Global Datastore cluster to cache all relational write activities globally.Why Incorrect: ElastiCache for Redis is an in-memory caching layer, not a persistent primary relational database solution capable of managing complex ACID-compliant transaction tables safely.F) Store all transactional records as flat objects in Amazon S3, utilizing Cross-Region Replication (CRR) and querying via Amazon Athena.Why Incorrect: Amazon S3 combined with Athena is an object-based analytical query pattern. It lacks the low-latency indexing, row-level locking, and high-concurrency write capabilities required for a live e-commerce transactional database.Question 3: Application Services and Cost OptimizationAn application running on Amazon ECS powered by AWS Fargate processes messages from an Amazon SQS queue. The incoming workload experiences unpredictable, massive spikes in traffic throughout the day. Management wants to optimize operational costs while ensuring that messages do not remain unprocessed in the queue for more than 15 minutes. Which scaling and pricing strategy achieves this most effectively?A) Configure the ECS Service Auto Scaling policy based on Average CPU Utilization using 100% On-Demand Capacity Providers.Why Incorrect: CPU utilization does not reliably correlate with queue backlog size; tasks could be idle waiting for network I/O while messages pile up. Furthermore, relying entirely on On-Demand capacity is not the most cost-effective solution for stateless, queue-driven workers.B) Configure the ECS Service Auto Scaling policy based on the ApproximateNumberOfMessagesVisible metric per task using a combination of Fargate On-Demand and Fargate Spot Capacity Providers, prioritizing Spot.Why Correct: Scaling based on the queue backlog size per task directly targets the performance SLA (processing within 15 minutes). Utilizing Fargate Spot for fault-tolerant, stateless queue consumers provides up to a 70% cost reduction compared to On-Demand pricing, while keeping a baseline of On-Demand ensures availability if Spot capacity is temporarily unavailable.C) Purchase All Upfront EC2 Reserved Instances to run a dedicated ECS EC2 cluster scaled constantly to meet maximum historical peak capacity.Why Incorrect: Running instances at peak capacity continuously creates massive idle resource waste during low-traffic periods. This completely eliminates the financial benefits of elastic cloud scaling.D) Keep a fixed number of ECS Fargate tasks running continuously, covered fully by a Compute Savings Plan to guarantee predictable flat pricing.Why Incorrect: A fixed task count cannot adapt to unpredictable spikes in traffic. During massive bursts, a static pool of workers will fall behind, failing the operational constraint to process messages within 15 minutes.E) Schedule the ECS Fargate task counts using time-based cron scaling actions to scale out exclusively during business hours using 100% Spot instances.Why Incorrect: Scheduled scaling assumes predictable traffic patterns. Because the prompt states that the spikes are unpredictable, cron-based scaling will cause messages to accumulate unprocessed outside of the scheduled windows.F) Set up an EC2 Auto Scaling group utilizing Amazon EBS-optimized instances, configured to scale dynamically based on the memory utilization metrics of the instances.Why Incorrect: Memory utilization is a poor indicator of SQS queue volume. Additionally, managing underlying EC2 clusters manually introduces unnecessary operational overhead compared to Fargate, and raw EC2 instances scale out slower during sudden traffic spikes.Welcome to the Interview Questions Tests to help you prepare for your AWS Interview Questions Practice Test.You can retake the exams as many times as you wantThis is a huge original question bankYou get support from instructors if you have questionsEach question has a detailed explanationMobile-compatible with the Udemy appI hope that by now you're convinced! And there are a lot more questions inside the course.