Setting Up a Read Replica for an RDS Database

Introduction

Setting up a read replica for an RDS database is crucial for enhancing database performance and scalability. By offloading read traffic from the primary database, read replicas can help in distributing the workload, improving response times, and ensuring high availability. This guide will walk you through the process of setting up a read replica using Pulumi and TypeScript, leveraging AWS services like Amazon RDS and AWS IAM.

Solution Overview

In this solution, we will set up a read replica for an RDS database using Pulumi with TypeScript. The key services involved are Amazon RDS and AWS IAM.

Step-by-Step Explanation

Step 1: Install Pulumi Packages

Ensure you have Pulumi and the AWS SDK installed. You can do this by running:

npm install @pulumi/pulumi @pulumi/aws

Step 2: Create an RDS Instance

First, create the primary RDS instance if you don’t already have one. Here’s an example:

import * as aws from "@pulumi/aws";

const dbInstance = new aws.rds.Instance("dbInstance", {
    engine: "mysql",
    instanceClass: "db.t2.micro",
    allocatedStorage: 20,
    dbName: "mydatabase",
    username: "admin",
    password: "password",
});

Step 3: Create the Read Replica

Next, create the read replica for the primary RDS instance:

const readReplica = new aws.rds.Instance("readReplica", {
    engine: dbInstance.engine,
    instanceClass: dbInstance.instanceClass,
    sourceDbInstanceIdentifier: dbInstance.id,
});

Step 4: Export Outputs

Finally, export the endpoints of both the primary and read replica instances:

export const primaryEndpoint = dbInstance.endpoint;
export const replicaEndpoint = readReplica.endpoint;

Key Points

• Installation: Ensure Pulumi and AWS SDK are installed.
• Primary Instance: Create your primary RDS instance.
• Read Replica: Set up the read replica linked to the primary instance.
• Export Endpoints: Make the endpoints available for further use.

Conclusion

In this guide, we demonstrated how to set up a read replica for an RDS database using Pulumi with TypeScript. By creating a primary RDS instance and a read replica, you can enhance the performance and scalability of your database infrastructure. Exporting the endpoints of both instances allows for easy integration into your applications.

Full Code Example

import * as aws from "@pulumi/aws";

// Create the primary RDS cluster
const dbCluster = new aws.rds.Cluster("dbCluster", {
    engine: "aurora-mysql",
    masterUsername: "admin",
    masterPassword: "password",
    dbSubnetGroupName: "my-subnet-group",
    skipFinalSnapshot: true,
});

// Create the primary RDS instance
const dbInstance = new aws.rds.ClusterInstance("dbInstance", {
    clusterIdentifier: dbCluster.id,
    instanceClass: "db.t2.micro",
    engine: "aurora-mysql",
});

// Create the read replica for the primary RDS cluster
const readReplica = new aws.rds.ClusterInstance("readReplica", {
    clusterIdentifier: dbCluster.id,
    instanceClass: "db.t2.micro",
    engine: "aurora-mysql",
});

// Export the endpoints of both the primary and read replica instances
export const primaryEndpoint = dbInstance.endpoint;
export const replicaEndpoint = readReplica.endpoint;