Launching an RDS instance in AWS - Mini Project: Build & Apply

Launching an RDS instance

📖 Scenario: You are setting up a simple database for a small web application. You want to launch an Amazon RDS instance to store your app's data securely and reliably.

🎯 Goal: Create an AWS CloudFormation template that launches a basic Amazon RDS instance with the specified settings.

📋 What You'll Learn

Use AWS CloudFormation YAML syntax

Create an RDS DB instance resource

Specify DB instance class, engine, and allocated storage

Set master username and password parameters

Add a DB subnet group referencing two subnets

Ensure the DB instance is publicly accessible

💡 Why This Matters

🌍 Real World

Launching an RDS instance is a common task when setting up backend databases for web applications or services in AWS.

💼 Career

Cloud architects and DevOps engineers often write CloudFormation templates to automate infrastructure deployment, including databases like RDS.

1

Create the CloudFormation template skeleton

Start by creating a CloudFormation template with the AWSTemplateFormatVersion set to '2010-09-09' and an empty Resources section.

AWS

AWSTemplateFormatVersion: '2010-09-09'
Resources:
  # Your code here

Need a hint?

CloudFormation templates start with AWSTemplateFormatVersion and have a Resources section.

2

Add parameters for DB credentials

Add two parameters named DBUsername and DBPassword under Parameters. Set DBUsername as a string with default admin. Set DBPassword as a string with NoEcho true to hide the password.

AWS

AWSTemplateFormatVersion: '2010-09-09'
Parameters:
  # Your code here
Resources: {}

Need a hint?

Parameters let you input values when launching the stack. Use NoEcho: true to keep passwords hidden.

3

Add a DB subnet group resource

Add a resource named DBSubnetGroup of type AWS::RDS::DBSubnetGroup. Set its DBSubnetGroupDescription to 'Subnet group for RDS' and SubnetIds to a list containing subnet-12345678 and subnet-87654321.

AWS

AWSTemplateFormatVersion: '2010-09-09'
Parameters:
  DBUsername:
    Type: String
    Default: admin
  DBPassword:
    Type: String
    NoEcho: true
Resources:
  # Your code here

Need a hint?

DB subnet groups tell RDS which subnets to use for the database.

4

Add the RDS DB instance resource

Add a resource named MyDBInstance of type AWS::RDS::DBInstance. Set its DBInstanceClass to db.t3.micro, Engine to mysql, AllocatedStorage to 20, MasterUsername to !Ref DBUsername, MasterUserPassword to !Ref DBPassword, DBSubnetGroupName to !Ref DBSubnetGroup, and PubliclyAccessible to true.

AWS

AWSTemplateFormatVersion: '2010-09-09'
Parameters:
  DBUsername:
    Type: String
    Default: admin
  DBPassword:
    Type: String
    NoEcho: true
Resources:
  DBSubnetGroup:
    Type: AWS::RDS::DBSubnetGroup
    Properties:
      DBSubnetGroupDescription: 'Subnet group for RDS'
      SubnetIds:
        - subnet-12345678
        - subnet-87654321
  # Your code here

Need a hint?

This resource launches the actual RDS database instance with your settings.