AWS Cloud Architect Interview Series | SCENARIO based Questions | Part - 1

Introduction

This tutorial focuses on preparing for AWS Cloud Architect interviews, specifically addressing scenario-based questions related to migrating a 3-tier web application from on-premises infrastructure to the cloud. Understanding how to approach these questions will enhance your interview performance and demonstrate your cloud architecture knowledge effectively.

Step 1: Understand the 3-Tier Architecture

Familiarize yourself with the components of a 3-tier architecture:

• Presentation Tier: The user interface (UI) layer where users interact with the application.
• Application Tier: The business logic layer where data processing occurs.
• Data Tier: The database layer that stores application data.

Practical Advice

• Review how each tier interacts with the others.
• Be prepared to explain how these tiers can be implemented in AWS using services like Amazon EC2 (for the application layer) and Amazon RDS (for the database layer).

Step 2: Assess Migration Strategies

When migrating a 3-tier application to AWS, consider the following strategies:

1. Rehosting (Lift and Shift): Move applications to the cloud without changes.
2. Replatforming: Make minimal modifications to optimize for the cloud.
3. Refactoring: Redesign the application to take full advantage of cloud features.

Practical Advice

• Analyze the pros and cons of each strategy.
• Prepare to discuss which strategy would be best for different scenarios based on cost, performance, and time.

Step 3: Identify AWS Services for Each Tier

Choose the appropriate AWS services for each tier of the architecture:

• Presentation Tier: Use AWS Elastic Load Balancer (ELB) and Amazon CloudFront for distribution and scaling.
• Application Tier: Use Amazon EC2, AWS Lambda (for serverless applications), or Amazon ECS (for containerized applications).
• Data Tier: Use Amazon RDS for relational databases or Amazon DynamoDB for NoSQL databases.

Practical Advice

• Be ready to explain the reasons for your service choices and how they fit into the overall architecture.

Step 4: Discuss Security and Compliance

Security is paramount when migrating to the cloud. Address these key areas:

• Data Encryption: Implement encryption in transit and at rest.
• Access Control: Use AWS IAM for managing access permissions.
• Compliance: Ensure that your architecture meets industry standards and regulations.

Practical Advice

• Familiarize yourself with AWS security best practices and compliance frameworks relevant to your industry.

Step 5: Prepare for Common Interview Questions

Anticipate questions that may arise during your interview, such as:

• How would you ensure high availability in your architecture?
• What measures would you take to optimize cost during migration?
• How would you handle data transfer from on-premises to AWS?

Practical Advice

• Frame your answers using the STAR method (Situation, Task, Action, Result) to structure your responses clearly.

Conclusion

Preparing for AWS Cloud Architect interviews requires a solid understanding of cloud migration strategies and architecture principles. Focus on the 3-tier architecture, select the right AWS services, ensure security compliance, and practice common interview questions. By mastering these topics, you will be well-equipped to handle scenario-based questions effectively and demonstrate your expertise in cloud architecture.