Day-30 | THREE-TIER ARCHITECTURE IMPLEMENTATION ON AWS | #aws #abhishekveeramalla

Summary

In the final episode of the AWS DevOps Zero to Hero series, Abhishek dives deep into the three-tier architecture model on AWS, explaining its components—front-end, back-end, and database—and how to implement it using key AWS services like EC2, RDS, and Auto Scaling. He also discusses when to use this model in interviews, particularly in contexts where EC2-based solutions are preferred over serverless or Kubernetes architectures. The video offers practical insights, a step-by-step guide, and tips for scaling applications in AWS, helping viewers build their expertise for real-world AWS DevOps roles.

Takeaways

• 😀 The course 'Free AWS DevOps Zero to Hero' has concluded with this video, but AWS-related content will continue on the channel.
• 😀 The three-tier architecture consists of three main layers: Frontend (User Interface), Backend (Application Logic), and Database.
• 😀 A typical three-tier application involves user interaction with a UI, which sends requests to the backend, which in turn queries a database.
• 😀 Applications can be classified as two-tier (UI + Backend) or three-tier (UI + Backend + Database), depending on the architecture complexity.
• 😀 AWS VPC (Virtual Private Cloud) is used to isolate different projects and secure resources from other applications within the same AWS account.
• 😀 Subnets in the VPC are divided into private subnets for frontend, backend, and database applications to ensure scalability and security.
• 😀 Auto Scaling Groups in EC2 instances are used to deploy applications across multiple Availability Zones for high availability and load balancing.
• 😀 Amazon RDS (Relational Database Service) is used for database management, with primary and secondary instances for data redundancy and failover.
• 😀 The use of Elastic Load Balancer (ELB) helps distribute incoming traffic across multiple EC2 instances, enhancing scalability and fault tolerance.
• 😀 While the three-tier architecture is foundational, many organizations are shifting toward serverless and containerized (e.g., Kubernetes) architectures for more flexibility and scalability.

Q & A

What is a Three-Tier Architecture on AWS?

A Three-Tier Architecture on AWS is a model that divides an application into three layers: the frontend (user interface), the backend (business logic), and the database (data storage). It enables scalable and secure application deployment, with each tier performing a specific function.

What is the significance of using EC2 instances in a Three-Tier Architecture?

EC2 instances are used in the backend and frontend tiers of a Three-Tier Architecture to run the application logic and handle user requests. They provide the compute capacity needed to process requests, scale automatically via Auto Scaling, and run applications in multiple availability zones for high availability.

Why is a Virtual Private Cloud (VPC) necessary for this architecture?

A VPC is used to isolate the application within a private network, ensuring security and separation from other projects within the same AWS account. It allows you to define your network’s IP address range and control routing and access between different layers of the application.

How does Auto Scaling work in the context of a Three-Tier Architecture?

Auto Scaling automatically adjusts the number of EC2 instances running in the frontend and backend tiers based on traffic. It ensures that your application scales up during high demand and scales down during low demand, optimizing costs and ensuring availability.

What role does AWS RDS play in the Three-Tier Architecture?

AWS RDS (Relational Database Service) is used in the database tier to host and manage databases like MySQL, PostgreSQL, or others. It simplifies database management by providing automatic backups, scaling, and high availability, ensuring that data is safely stored and accessible by the backend.

Why is there a need for a disaster recovery strategy in this architecture?

A disaster recovery strategy ensures that the application remains available even if one region or availability zone experiences failure. By creating VPCs in different regions, you can replicate critical components like EC2 instances and RDS databases, providing redundancy and minimizing downtime.

What is the role of Route 53 and CDN in this architecture?

Route 53 is used for DNS management, directing user traffic to the correct resources. A Content Delivery Network (CDN) like CloudFront is used to cache and serve static content faster, improving the user experience by reducing latency.

When should you mention the Three-Tier Architecture model in an interview?

You should mention the Three-Tier Architecture model when applying for roles that require experience with EC2-based applications and traditional server hosting. However, if the job focuses on containerized applications or serverless architectures, you should discuss containerization technologies like Kubernetes instead.

How does the architecture described in the video compare to modern Kubernetes-based architectures?

The architecture described in the video uses EC2 instances and traditional scaling methods, while modern Kubernetes-based architectures rely on containerization for application deployment. Kubernetes allows for more efficient management of distributed applications and can simplify the scaling and deployment of microservices, whereas EC2 instances are typically more static and require more manual configuration.

Why is it important to have multiple availability zones in this architecture?

Multiple availability zones ensure that your application is highly available and resilient to failure. By distributing EC2 instances, load balancers, and databases across multiple zones, you reduce the risk of downtime due to zone-specific failures, maintaining the continuity of the service.