Creating a VPC With Public and Private Subnets in Us-East-1

Introduction

In this guide, we will create an Amazon VPC with both public and private subnets in the us-east-1 region using Pulumi. The key services involved are AWS VPC, subnets, and internet gateway.

Step-by-Step Explanation

Step 1: Set up the Pulumi project

First, ensure you have the Pulumi CLI installed and configured. Create a new Pulumi project:

pulumi new aws-typescript

Step 2: Define the VPC

In your index.ts file, define a new VPC:

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

const vpc = new aws.ec2.Vpc("my-vpc", {
    cidrBlock: "10.0.0.0/16",
    enableDnsHostnames: true,
    enableDnsSupport: true,
});

Step 3: Create Public Subnets

Next, create public subnets within the VPC:

const publicSubnet1 = new aws.ec2.Subnet("public-subnet-1", {
    vpcId: vpc.id,
    cidrBlock: "10.0.1.0/24",
    availabilityZone: "us-east-1a",
    mapPublicIpOnLaunch: true,
});

const publicSubnet2 = new aws.ec2.Subnet("public-subnet-2", {
    vpcId: vpc.id,
    cidrBlock: "10.0.2.0/24",
    availabilityZone: "us-east-1b",
    mapPublicIpOnLaunch: true,
});

Step 4: Create Private Subnets

Similarly, create private subnets within the VPC:

const privateSubnet1 = new aws.ec2.Subnet("private-subnet-1", {
    vpcId: vpc.id,
    cidrBlock: "10.0.3.0/24",
    availabilityZone: "us-east-1a",
});

const privateSubnet2 = new aws.ec2.Subnet("private-subnet-2", {
    vpcId: vpc.id,
    cidrBlock: "10.0.4.0/24",
    availabilityZone: "us-east-1b",
});

Step 5: Create an Internet Gateway

Create an Internet Gateway and attach it to the VPC:

const igw = new aws.ec2.InternetGateway("igw", {
    vpcId: vpc.id,
});

Step 6: Create Route Tables

Create route tables for the public and private subnets:

const publicRouteTable = new aws.ec2.RouteTable("public-route-table", {
    vpcId: vpc.id,
    routes: [{
        cidrBlock: "0.0.0.0/0",
        gatewayId: igw.id,
    }],
});

const privateRouteTable = new aws.ec2.RouteTable("private-route-table", {
    vpcId: vpc.id,
});

Step 7: Associate Route Tables with Subnets

Associate the route tables with the respective subnets:

new aws.ec2.RouteTableAssociation("public-subnet-1-association", {
    subnetId: publicSubnet1.id,
    routeTableId: publicRouteTable.id,
});

new aws.ec2.RouteTableAssociation("public-subnet-2-association", {
    subnetId: publicSubnet2.id,
    routeTableId: publicRouteTable.id,
});

new aws.ec2.RouteTableAssociation("private-subnet-1-association", {
    subnetId: privateSubnet1.id,
    routeTableId: privateRouteTable.id,
});

new aws.ec2.RouteTableAssociation("private-subnet-2-association", {
    subnetId: privateSubnet2.id,
    routeTableId: privateRouteTable.id,
});

Conclusion

By following these steps, you have successfully created a VPC with both public and private subnets in the us-east-1 region using Pulumi. This setup is essential for deploying applications that require both internet-facing and internal-only resources.

Full Code Example

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

// Create a new VPC
const vpc = new aws.ec2.Vpc("my-vpc", {
    cidrBlock: "10.0.0.0/16",
    enableDnsHostnames: true,
    enableDnsSupport: true,
});

// Create Public Subnets
const publicSubnet1 = new aws.ec2.Subnet("public-subnet-1", {
    vpcId: vpc.id,
    cidrBlock: "10.0.1.0/24",
    availabilityZone: "us-east-1a",
    mapPublicIpOnLaunch: true,
});

const publicSubnet2 = new aws.ec2.Subnet("public-subnet-2", {
    vpcId: vpc.id,
    cidrBlock: "10.0.2.0/24",
    availabilityZone: "us-east-1b",
    mapPublicIpOnLaunch: true,
});

// Create Private Subnets
const privateSubnet1 = new aws.ec2.Subnet("private-subnet-1", {
    vpcId: vpc.id,
    cidrBlock: "10.0.3.0/24",
    availabilityZone: "us-east-1a",
});

const privateSubnet2 = new aws.ec2.Subnet("private-subnet-2", {
    vpcId: vpc.id,
    cidrBlock: "10.0.4.0/24",
    availabilityZone: "us-east-1b",
});

// Create an Internet Gateway
const igw = new aws.ec2.InternetGateway("igw", {
    vpcId: vpc.id,
});

// Create Route Tables
const publicRouteTable = new aws.ec2.RouteTable("public-route-table", {
    vpcId: vpc.id,
    routes: [{
        cidrBlock: "0.0.0.0/0",
        gatewayId: igw.id,
    }],
});

const privateRouteTable = new aws.ec2.RouteTable("private-route-table", {
    vpcId: vpc.id,
});

// Associate Route Tables with Subnets
new aws.ec2.RouteTableAssociation("public-subnet-1-association", {
    subnetId: publicSubnet1.id,
    routeTableId: publicRouteTable.id,
});

new aws.ec2.RouteTableAssociation("public-subnet-2-association", {
    subnetId: publicSubnet2.id,
    routeTableId: publicRouteTable.id,
});

new aws.ec2.RouteTableAssociation("private-subnet-1-association", {
    subnetId: privateSubnet1.id,
    routeTableId: privateRouteTable.id,
});

new aws.ec2.RouteTableAssociation("private-subnet-2-association", {
    subnetId: privateSubnet2.id,
    routeTableId: privateRouteTable.id,
});