Easy Ways to Prepare for AWS Questions in 2025

Mostly Asked AWS Interview Questions in 2025

Impact-Site-Verification: c45724be-8409-48bd-b93e-8026e81dc85aAmazon Web Services (AWS) has consistently remained at the forefront of cloud computing. With organizations migrating their infrastructures to the cloud, AWS-certified professionals are in high demand. Cracking an AWS interview in 2025 demands not just conceptual clarity but also hands-on familiarity with AWS services. In this blog, we’ll explore some of the most frequently asked AWS interview questions for 2025, structured clearly and concisely.

Let’s dive deep into the questions and understand how you can answer them effectively in interviews.

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What Is Amazon VPC?

Amazon Virtual Private Cloud (VPC) allows users to launch AWS resources in a logically isolated virtual network. It mimics a traditional on-premise network setup but provides advanced flexibility and scalability.

Key Features:

• Subnet creation (public/private)
• Route tables for directing traffic
• Internet Gateway and NAT Gateways for internet access
• Security Groups and Network ACLs for network-level security

Real-World Example:

Consider an e-commerce application where your web servers reside in public subnets while your databases are securely tucked into private subnets. VPC lets you control this setup with precision.

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What Is EC2?

Elastic Compute Cloud (EC2) is AWS’s IaaS (Infrastructure as a Service) offering that allows you to run virtual machines in the cloud.

Highlights:

• On-demand, spot, and reserved instances
• Wide range of instance types optimized for compute, memory, or storage
• Custom Amazon Machine Images (AMIs)
• Integration with other services like EBS, Auto Scaling, and Load Balancers

Interview Tip:

Explain how EC2 allows businesses to avoid upfront infrastructure costs and scale applications efficiently as per demand.

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What Is AWS CloudWatch?

Amazon CloudWatch is a monitoring and observability service that provides real-time insights into your AWS infrastructure and applications.

Use Cases:

• Monitor CPU, disk, and network metrics of EC2 instances
• Create alarms and notifications
• Analyze logs and set dashboards
• Integrated with over 70 AWS services

Pro Tip:

Discuss how CloudWatch allows proactive resource management and cost optimization.

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What Is Auto Scaling?

Auto Scaling automatically adjusts the number of EC2 instances in a group to maintain performance and minimize costs.

Advantages:

• Responds to traffic spikes and drops automatically
• Health checks and replacement of unhealthy instances
• Scheduled and dynamic scaling policies

Sample Scenario:

Imagine a retail website experiencing high traffic during holiday sales. Auto Scaling ensures enough instances are added to handle the load and then reduced afterward.

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Define AWS Elastic Transcoder

Elastic Transcoder is a media transcoding service that simplifies converting media files to different formats for compatibility across devices.

Why Use It?

• Supports a wide range of audio and video formats
• Predefined transcoding presets for different devices
• Integration with Amazon S3 and IAM

Use Case:

A video-streaming startup can use Elastic Transcoder to ensure their content is available in mobile-friendly, browser-optimized formats.

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How Do You Monitor AWS Services?

Monitoring AWS services involves using a mix of AWS-native and third-party tools.

Tools and Strategies:

• CloudWatch: For metrics, logs, alarms
• AWS CloudTrail: For audit logs of user/API activity
• AWS Config: For compliance and configuration monitoring
• Third-party tools: Datadog, Splunk, New Relic

Interview Insight:

Explain how proactive monitoring prevents outages and helps in capacity planning.

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How Does AWS Lambda Work?

AWS Lambda is a serverless computing service that lets you run code without provisioning or managing servers.

How It Works:

1. Upload your code
2. Set a trigger (like an S3 upload or API Gateway call)
3. Lambda runs the code and handles scaling and fault tolerance automatically

Benefits:

• Pay-per-use model
• Highly scalable
• Fast deployment and reduced operational overhead

Sample Use Case:

Use Lambda to resize images automatically when a new file is uploaded to an S3 bucket.

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What Are The Different Types Of Cloud Services?

Understanding cloud service models is essential for any AWS professional.

Types:

1. Infrastructure as a Service (IaaS): EC2, EBS
2. Platform as a Service (PaaS): AWS Elastic Beanstalk
3. Software as a Service (SaaS): AWS Chime, WorkDocs
4. Function as a Service (FaaS): AWS Lambda

Key Differentiators:

• Level of control vs ease of use
• Responsibility matrix shifts between provider and user

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What Is A VPC?

Though asked earlier, this is often repeated to test in-depth understanding.

Summary:

A VPC is a logically isolated network in AWS. It allows full control over network topology, IP addressing, and security.

Components:

• Subnets
• Route Tables
• Gateways
• Security mechanisms (ACLs, SGs)

Interview Angle:

Employers look for candidates who understand not just what a VPC is but how to architect secure, scalable, and highly available applications within it.

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Frequently Asked Questions (FAQs)

Q1: Can Auto Scaling Work Without Load Balancer?

Yes, but using it with an ELB ensures proper traffic distribution.

Q2: How Is Lambda Billed?

Based on the number of requests and execution time (in GB-seconds).

Q3: What’s The Difference Between CloudWatch And CloudTrail?

CloudWatch monitors performance; CloudTrail logs API activities.

Q4: How Secure Is AWS VPC?

VPC offers layered security using Security Groups, NACLs, and flow logs for auditing.

Q5: Is It Necessary To Use IAM With All Services?

Yes, IAM governs access and permissions across AWS.

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Final Thoughts

Mastering these AWS services and understanding how they interact within an ecosystem will significantly boost your chances in an interview. Companies want cloud professionals who not only understand definitions but can apply these tools to solve real-world problems. Practice hands-on labs, set up your AWS free-tier environment, and run test projects to solidify your knowledge.

By being confident, clear, and technically sound, you can ace your AWS interview in 2025.