Objectives

To design and construct an Amazon Virtual Private Cloud (VPC) architecture that includes an EC2 instance within a public subnet and a database instance within a private subnet

Problem Statement and Motivation

Real-Time Scenario:

James, a systems engineer at a startup company, is tasked with developing a web application with a secure, robust, and scalable backend database.

The company plans to utilize AWS RDS for the database, while the application will be deployed on an EC2 instance.

James must ensure a secure VPC setup where the EC2 instance resides in the public subnet and the RDS DB instance in a private subnet.

Problem Statement and Motivation

Expected Solution:

As a cloud architect, your objective is to assist James in developing an AWS VPC that hosts both an EC2 instance and a database instance.

The EC2 instance, serving the web application, should be placed in a public subnet, while the DB instance should be secured in a private subnet.

You are expected to provide step-by-step instructions for creating and configuring these AWS resources, ensuring system security, reliability, and accessibility.

Solution

My solution is to create a VPC with two Amazon EC2 instances in different availability zones and separate public subnets in a region. Then the RDS database supporting multi availability zones is created in a private subnet to only allow data access from the EC2 instances within the security group. Http requests a forwarded from the Internet Gateway to the EC2 instances which can access the data from the RDS database and send the response via Internet Gateway to the client.

The manual steps to achieve the same result using the AWS management console are documented here

Prerequisites

You have access to AWS services, for example via Free tier AWS account.
AWS CLI and Terraform are already installed.

Usage

1. Open terminal
2. Before you can execute the terraform script, your need to configure your aws environment first.
aws configure
AWS Access Key ID: See IAM > Security credentials > Access keys > Create access key
AWS Secret Access Key: See IAM > Security credentials > Access keys > Create access key
Default region name: us-east-1
Default output format: json
3. Now you can apply the terraform changes.
terraform init
terraform apply --auto-approve
Result: Calling the URL from the web browser should display the static web page
4. At the end you can cleanup the created AWS resources.
terraform destroy --auto-approve