How to host ExpressJs App to Aws EC2

To host an Express.js application on AWS EC2, you'll need to follow several steps, including setting up your EC2 instance, configuring it, deploying your Express.js application, and setting up any necessary networking and security settings. Below is a detailed guide:

Step 1: Launch an EC2 Instance

Sign in to AWS Console: Go to the AWS Management Console and sign in.
Navigate to EC2: Click on the "Services" dropdown and select "EC2" under the Compute section.
Launch Instance: Click on the "Launch Instance" button to start the instance creation process.
Choose an AMI: Select an Amazon Machine Image (AMI) that matches your operating system requirements. For example, choose an Amazon Linux or Ubuntu Server AMI.
Choose Instance Type: Select an instance type based on your application's resource needs. For development or small-scale applications, a t2.micro instance might suffice.
Configure Instance: Configure instance details like network settings, IAM role (if needed), and other settings according to your requirements.
Add Storage: Allocate storage for your instance. The default settings are usually fine, but adjust as necessary.
Add Tags (Optional): Add tags to your instance for better organization and management.
Configure Security Group: Create a new security group or select an existing one. Ensure that ports required by your Express.js application are open (e.g., HTTP port 80, HTTPS port 443).
Review and Launch: Review your instance configuration and click "Launch" to start the instance.
Key Pair: Choose an existing key pair or create a new one. This key pair will be used for SSH access to your instance.
Launch Instances: Click "Launch Instances" to create the instance.

Step 2: Connect to Your EC2 Instance

Get the Public IP: Once the instance is launched, note down its public IP address.
SSH into the Instance: Open your terminal or SSH client and run the following command to connect to your instance:
```
ssh -i /path/to/your-key.pem ec2-user@your-instance-public-ip
```
Replace /path/to/your-key.pem with the path to your private key file and your-instance-public-ip with the actual public IP address of your EC2 instance.

Step 3: Install Node.js and npm

Update Packages: Run the following commands to update the package repositories on your EC2 instance:
```
sudo yum update -y   # For Amazon Linux
sudo apt update      # For Ubuntu
```

Install Node.js and npm: Install Node.js and npm using the following commands:

sudo yum install nodejs npm -y   # For Amazon Linux
sudo apt install nodejs npm -y   # For Ubuntu

Step 4: Deploy Your Express.js Application

Upload Your Application: Upload your Express.js application code to the EC2 instance using SCP, SFTP, or any other method you prefer.
Install Application Dependencies: Navigate to your application directory and install dependencies using npm:
```
npm install
```
Start Your Application: Start your Express.js application using the appropriate command. For example, if your entry point is app.js, you can start the application with:
```
node app.js
```

Step 5: Configure Networking and Security

Configure Security Group: Ensure that your EC2 instance's security group allows inbound traffic on the port your Express.js application is listening on (e.g., port 3000).
Optional - Configure Domain Name: If you want to access your application using a custom domain name, configure the domain name to point to your EC2 instance's public IP address or assign an Elastic IP address to your instance.

Step 6: Monitoring and Maintenance

Regularly monitor your EC2 instance for performance and security. Set up alarms in AWS CloudWatch for metrics like CPU utilization, memory usage, etc. Perform routine maintenance tasks such as applying security updates and patches to your instance.

By following these steps, you should be able to successfully host your Express.js application on AWS EC2. Make sure to follow security best practices and optimize your instance for cost efficiency.