Here are some of the most commonly asked AWS interview questions and answers, suitable for freshers and candidates with 1–3 years of experience.
Answer:
AWS (Amazon Web Services) is a cloud computing platform provided by Amazon that offers a wide range of on-demand cloud services. It enables businesses and developers to build, deploy, and manage applications without investing in physical infrastructure.
AWS provides services in areas such as:
Key Features of AWS:
Answer:
AWS provides hundreds of cloud services. Some of the most commonly used services are:
Answer:
Amazon EC2 (Elastic Compute Cloud) is a virtual machine that provides scalable computing capacity in the AWS cloud.
It allows users to launch virtual servers with different operating systems and hardware configurations according to application requirements.
Features of EC2:
Answer:
An Amazon S3 Bucket is a storage container used to store objects such as documents, images, videos, backups, and application data.
S3 is designed for high durability, scalability, and security.
Features:
| Amazon S3 | Amazon EBS |
|---|---|
| Object Storage | Block Storage |
| Stores files and objects | Stores disk volumes |
| Accessible over the internet | Attached directly to EC2 |
| Highly scalable | Limited to attached instance |
| Used for backups, images, videos | Used for operating systems and databases |
IAM (Identity and Access Management)
IAM is used to securely manage users, groups, roles, and permissions in AWS.
Functions of IAM:
KMS (Key Management Service)
KMS is used to create and manage encryption keys for protecting AWS resources and sensitive data.
Functions of KMS:
Horizontal Scaling (Scale Out)
Horizontal scaling increases system capacity by adding more servers or instances.
Advantages:
Vertical Scaling (Scale Up)
Vertical scaling increases the resources (CPU, RAM, Storage) of an existing server.
Advantages:
Answer:
AWS Lambda is a serverless computing service that lets you run code without provisioning or managing servers.
It automatically executes code in response to events such as:
Benefits:
| Serverless | Containers |
|---|---|
| No server management | Servers or clusters must be managed |
| Automatic scaling | Manual or orchestrated scaling |
| Pay per execution | Pay for running containers |
| Fast deployment | More configuration required |
| Example: AWS Lambda | Example: ECS, EKS |
| Amazon RDS | Amazon DynamoDB |
|---|---|
| Relational Database | NoSQL Database |
| Supports SQL | Key-value and Document Database |
| MySQL, PostgreSQL, Oracle, SQL Server | Proprietary AWS NoSQL |
| Fixed schema | Flexible schema |
| Best for transactional applications | Best for high-performance web and mobile applications |
Answer:
Auto Scaling is an AWS service that automatically adjusts the number of Amazon EC2 instances based on application demand. It ensures that your application always has the right amount of computing resources while minimizing costs.
Benefits of Auto Scaling:
Answer:
An Amazon Machine Image (AMI) is a pre-configured template used to launch EC2 instances.
An AMI includes:
Types of AMIs:
| Amazon CloudFront | Amazon S3 |
|---|---|
| Content Delivery Network (CDN) | Object Storage Service |
| Delivers cached content globally | Stores files and objects |
| Reduces latency | Stores original data |
| Uses Edge Locations | Uses AWS Regions |
| Improves website performance | Provides durable storage |
Answer:
Amazon VPC (Virtual Private Cloud) is a logically isolated virtual network within AWS where you can launch AWS resources securely.
It allows you to control networking configurations such as IP addresses, subnets, routing tables, and security.
Key Features:
| Amazon EBS | Amazon EFS |
|---|---|
| Block Storage | File Storage |
| Attached to one EC2 instance | Shared across multiple EC2 instances |
| High-performance storage | Scalable shared storage |
| Used for databases and operating systems | Used for shared applications and file systems |
Answer:
AWS CloudFormation is an Infrastructure as Code (IaC) service that allows you to create and manage AWS resources using JSON or YAML templates.
Instead of manually creating resources, you define them in templates.
Benefits:
Answer:
Amazon SNS (Simple Notification Service) is a fully managed messaging service used to send notifications to multiple subscribers.
SNS supports:
Common Use Cases:
Answer:
AWS CLI (Command Line Interface) is a command-line tool used to interact with AWS services.
Using AWS CLI, users can:
Advantages:
| Amazon RDS | Amazon Redshift |
|---|---|
| Relational Database | Data Warehouse |
| Designed for OLTP | Designed for OLAP |
| Supports transactions | Optimized for analytics |
| MySQL, PostgreSQL, Oracle, SQL Server | Columnar storage |
| Used for applications | Used for Business Intelligence and reporting |
Answer:
AWS CloudTrail is a service that records all API calls made within your AWS account.
It helps organizations monitor, audit, and troubleshoot AWS activities.
Features:
| CloudWatch Logs | CloudTrail |
|---|---|
| Stores application and system logs | Records AWS API calls |
| Used for monitoring applications | Used for auditing AWS activity |
| Helps troubleshoot applications | Tracks user actions |
| Supports log analysis | Supports security compliance |
Answer:
AWS Elastic Beanstalk is a Platform as a Service (PaaS) that makes it easy to deploy and manage web applications.
Developers only upload their application code, while AWS automatically handles:
Supported Languages:
| Amazon ECS | Amazon EKS |
|---|---|
| AWS-managed container service | Managed Kubernetes service |
| Simpler to configure | Supports Kubernetes ecosystem |
| Docker containers | Kubernetes containers |
| AWS-native orchestration | Kubernetes orchestration |
| Easier for beginners | Best for Kubernetes workloads |
| Amazon CloudFront | Amazon Route 53 |
|---|---|
| Content Delivery Network (CDN) | Domain Name System (DNS) Service |
| Delivers cached content | Resolves domain names |
| Improves website speed | Routes internet traffic |
| Uses Edge Locations | Uses DNS routing policies |
Answer:
AWS Serverless Application Model (SAM) is an open-source framework used to build, test, and deploy serverless applications on AWS.
It simplifies the creation of:
Advantages of AWS SAM:
