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Mubeen Babar
Mubeen Babar

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Creating a VPC and Launching a Web Application in an Amazon EC2 Instance

Task 1: Create a Virtual Private Cloud

CREATE A VPC, PUBLIC SUBNETS, ROUTE TABLE, AND INTERNET GATEWAY

  • At the top of the AWS Management Console, in the search bar, search for and choose VPC
  • Choose Create VPC
  • On the left side of the Create VPC console, locate the VPC settings section, and select VPC and more in the Resources to create section.
  • In the Name tag auto-generation section, select Auto-generate, if not already selected.
  • In the text box under the Auto-generate option, enter the name
  • In the IPv4 CIDR block section, enter 10.0.0.0/16
  • In the IPv6 CIDR block section, select the No IPv6 CIDR block option, if not already selected.
  • Leave the Tenancy section set to Default.
  • In the Number of Availability Zones (AZs) section, select 2
  • In the Number of public subnets section, select 2
  • In the Number of private subnets section, select 0
  • Expand the Customize subnets CIDR blocks option
  • In the first text box, enter the following: 10.0.0.0/24. This CIDR range contains all IP addresses starting with 10.0.0.x.
  • In the second text box, enter the following: 10.0.1.0/24. This CIDR range contains all IP addresses starting with 10.0.1.x.
  • In the NAT gateways section, select None
  • In the VPC endpoints section, select None
  • In the DNS options section, select both Enable DNS hostnames and Enable DNS resolution.

The DNS hostnames attribute determines whether instances launched in the VPC receive public DNS hostnames that correspond to their public IP addresses. The DNS resolution attribute determines whether DNS resolution through the Amazon DNS server is supported for the VPC.

  • Review the Preview section on the right side of the screen. This preview should include the name of your VPC, the two subnets you created, a public route table, and an Internet gateway.
  • If the Preview section presents the correct information, select Create VPC.

The Create VPC workflow screen appears. Wait for the workflow to finish. You should receive a message indicating everything created successfully.

Success

  • Review the details of the workflow. Note that the VPC workflow created your Internet gateway, attached the Internet gateway to your VPC, and associated your subnets to your route table. An example can be found below:

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  • Select View VPC

ADD A PUBLIC ROUTE TO THE ROUTE TABLE

  • Choose Route tables. Refresh the selection. Select the Main route table for lab-2-vpc

There is currently only one route used for all internal traffic within the VPC. To access the Internet, you must first add a route to the Internet gateway.

  • Select Edit routes
  • Select Add route
  • In the Destination column, locate the text box and enter the following: 0.0.0.0/0
  • In the Target column, locate the text box and select it. A list of options should present themselves. Select Internet Gateway. The id and name of your Internet Gateway should populate. Select the Internet Gateway ID named lab-2-igw
  • Select Save changes
  • You should receive an output message similar to the following: Updated routes for rtb-xxxxxxxxxxxxxxxx successfully
  • Navigate to the bottom of the VPC console and select the Routes tab, if not already selected.
  • Note the two routes:
  • An internal route for VPC traffic
  • A public route to the Internet by way of the Internet Gateway

The diagram below represents your new custom VPC:

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Congratulations! You successfully created a custom VPC, Internet gateway, route table, a public route to the Internet, and two public subnets in two separate availability zones.

Task 2: Create a VPC Security Group

  • In the left navigation pane, locate the Security section, and choose Security groups.
  • In the top-right area of your window, choose Create security group.
  • In the Basic details section, locate the Security group name text box and enter the value Web Security Group
  • In the Basic details section, locate the Description text box and enter the value Enable HTTP access from anywhere
  • In the Basic details section, locate the VPC text box, select the X to remove the default VPC, and choose the VPC with name lab-2-vpc. Once select, the lab-2-vpc
  • In the Inbound rules section, choose Add rule.
  • In the Type column, select the dropdown and choose HTTP
  • In the Source column, select the dropdown and choose Anywhere-IPv4
  • In the Description column, locate the text box and enter Allow web requests from anywhere
  • Navigate to the bottom of the Create security group window, and choose Create security group.

Congratulations! You successfully created a custom Security Group that allows inbound web traffic from anywhere.

Task 3: Launch Your Amazon EC2 Instance

  • At the top of the AWS Management Console, in the search bar, search for and choose EC2
  • In the left navigation pane, in the Instances section, choose Instances.
  • Choose Launch instances.
  • In the Name and tags section, locate the Name text box, and enter the value Web Application
  • In the Application and OS images section, locate the Quick start window, and select Amazon Linux 2023
  • Under the Quick start window, locate the Amazon Machine Image (AMI) dropdown and select the AMI named Amazon Linux 2023 AMI
  • Under the Description section, locate the Architecture dropdown and select 64-bit (x86)
  • In the Instance type section, locate the Instance type dropdown and select t3.micro
  • In the Key pair (login) section, locate the key pair name dropdown and select Proceed without a key pair (Not recommended)
  • In the Network settings section, select Edit.
  • Locate the VPC dropdown and select lab-2-vpc
  • Locate the Subnet dropdown and select lab-2-subnet-public-1-[az-a] where [az-a] is the first availability zone in your region.
  • Locate the Auto-assign public IP dropdown and select Enable

Note: This setting assigns a public IP address to the instance so you can access the application in your browser.

  • In the Firewall (security groups) section, choose Select an existing security group
  • Locate the Common security groups dropdown and select the security group named Web Security Group
  • You can leave the Configure storage section set to the default values.
  • Scroll down to the Advanced Details section, expand, the dropdown, and locate the User data text box.

Note: When you launch an instance in Amazon EC2, you have the option of passing user data to the instance that can be used to perform common automated configuration tasks and even run scripts after the instance starts.
Your instance uses an Amazon Linux 2023 operating system; therefore, you need to provide a shell script that will run when the instance starts. This script installs the required application dependencies and launches the application. Without this user data script, you would need to log in to the EC2 Instance and execute all of the commands yourself.

  • Copy the following script and paste it into the User data text box. To copy the script, you can use the Clipboard button, located in the top-right corner of the code box below:
#!/bin/bash -ex

# Update yum
yum -y update

#Install nodejs
yum -y install nodejs

# Create a dedicated directory for the application
mkdir -p /var/app

# Get the app from S3
wget https://aws-tc-largeobjects.s3-us-west-2.amazonaws.com/ILT-TF-100-TECESS-5/app/app.zip

# Extract it to the desired folder
unzip app.zip -d /var/app/
cd /var/app/

# Install dependencies
npm install

# Start the app
npm start

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This script performs the following tasks:
• Install system updates
• Install a source repository to download the Node.js installer
• Install Node.js
• Download the application code
• Create a dedicated directory for the web application
• Download and extract the application into the specified directory
• Install the application dependencies
• Set the listener port for the application
• Start the web application

  • In Summary section, for Number of instances text box, enter the value 1, if not already done.
  • Select Launch instance.
  • Wait for the instance to launch. You should receive an message indicating the launch completed. See the message below:

Successfully initiated launch of instance (instance-id)

  • Choose View all instances.

Note: You may need to refresh the Instances page for the instance to appear in the list of instances.
The instance should appear in a Pending or Initializing state, which means it is launching. When the Instance state changes to Running, the instance is booting.

  • To see the instance details, choose your Web Application instance.

To show more or less information in the Details tab, drag the window divider. You can review the instance details including the instance type, security settings, network settings, etc.

  • In the Instance window, at the top of the page, locate the Instance state and Status check columns. Wait for the values to indicate the following:

• Instance state: Running
• Status check: 2/2 checks passed

  • In the Details tab, locate the Public IPv4 address section, and copy the IP address

Note: If you refreshed the Instances window, you may need to choose your Web Application instance again.

  • Open a new browser tab and paste the IP address you copied in the previous step. You should see the following application screen.

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Note: If you use the open address link, your browser might try to browse to the application using
https://, which won’t work. The application can only be accessed using
http:// on port 80

The follow diagram represents the completed lab environment:

Image description

Once you access the web application successfully, you can close the browser tab.

Congratulations! You successfully created an EC2 Instance and deployed a web application using a user data script.

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