TLDR: This blog post explores the concept of three-tier architecture on AWS, detailing its components, advantages, and when to discuss it in job interviews. It also highlights the transition from traditional EC2 instances to modern containerized solutions.
In this final episode of the AWS DevOps Zero to Hero series, we delve into the three-tier architecture model on AWS. This model is crucial for understanding how applications are structured and deployed in a cloud environment. As we conclude this playlist, it's important to reflect on the journey we've taken, covering essential AWS concepts and services that are vital for aspiring DevOps engineers.
What is Three-Tier Architecture?
Three-tier architecture is a software architecture pattern that separates applications into three logical layers:
Presentation Layer (Front End): This is the user interface where users interact with the application. For example, when a user visits amazon.com, they see a web page that allows them to log in and search for products.
Application Layer (Back End): This layer processes user requests and contains the business logic. It communicates with the database to retrieve or store data.
Data Layer (Database): This layer is responsible for data storage and management. It typically involves a database management system (DBMS) that holds the application's data.
Example of Three-Tier Architecture
Consider a user searching for a product on Amazon. The user interface (front end) allows them to log in and search for products. Once the user selects a product, the request is sent to the back end, which processes the request and retrieves the product information from the database. The database then sends the information back to the back end, which displays it on the user interface.
Advantages of Three-Tier Architecture
Separation of Concerns: Each layer has distinct responsibilities, making the application easier to manage and scale.
Scalability: Each layer can be scaled independently based on demand. For instance, if the front end experiences high traffic, additional instances can be deployed without affecting the back end or database.
Flexibility: Changes can be made to one layer without impacting the others, allowing for easier updates and maintenance.
When to Discuss Three-Tier Architecture in Interviews
While discussing your experience with three-tier architecture in interviews, consider the following:
Relevance to Job Description: If the job requires knowledge of traditional EC2 instances and three-tier architecture, it is appropriate to mention your experience. However, if the role focuses on containerization or serverless architectures, it may be better to discuss those technologies instead.
Context of Implementation: Be prepared to explain the context in which you implemented the three-tier architecture, including the challenges faced and how you overcame them.
Implementing Three-Tier Architecture on AWS
To implement a three-tier architecture on AWS, follow these steps:
Create a Virtual Private Cloud (VPC): This isolates your application from other projects within the same AWS account. Define a CIDR block range for your VPC.
Set Up Subnets: Divide your VPC into three subnets:
Public Subnet: For the front-end application.
Private Subnet 1: For the back-end application.
Private Subnet 2: For the database.
Deploy EC2 Instances: Use Auto Scaling Groups to manage your front-end and back-end instances across multiple availability zones for high availability.
Database Setup: Utilize AWS RDS to create a primary and secondary database instance for redundancy.
Load Balancing: Implement an Elastic Load Balancer (ELB) to distribute incoming traffic across your EC2 instances.
Route 53: Use AWS Route 53 for DNS management to route user requests to the appropriate resources.
Diagram and Resources
For a clearer understanding, refer to the detailed blog created by a community member, which includes diagrams and step-by-step instructions for deploying a three-tier application on AWS. This resource will help you visualize the architecture and understand the flow of requests from the client to the database.
Conclusion
As we wrap up this series, it's essential to recognize the shift in cloud architecture from traditional three-tier models to modern containerized solutions. While three-tier architecture remains relevant, many organizations are moving towards Kubernetes and serverless architectures. Understanding both paradigms will enhance your skill set and prepare you for various roles in the cloud computing landscape.
Thank you for following this series, and I look forward to sharing more advanced AWS topics in future videos. Your feedback is invaluable, so please share your thoughts on this course and what you'd like to learn next.