An Application Load Balancer (ALB) in Amazon Web Services (AWS) acts as a single point of contact for managing incoming client traffic. It intelligently routes requests to targets in a target group based on content and maintains the client connections. SSL termination is a powerful feature that adds an extra layer of security. This article will walk you through how to configure an ALB and understand the benefits of SSL termination.

Configuring an Application Load Balancer

Step 1: Sign In to the AWS Management Console

• Navigate to https://aws.amazon.com/
• Enter your account credentials.

Step 2: Open the EC2 Dashboard

• On the AWS Management Console, navigate to the "Services" tab.
• Click on "EC2," then select "Target Groups" from the left-hand menu.

Step 3: Configure Routing

• Create a target group or select an existing one.
• Define the protocol as HTTP, the port as 8080, and the type of targets you'll be using(Instnaces).

Step 4: Create a Load Balancer

• Click on "EC2," then select "Load Balancer" from the left-hand menu.
• Click on "Create Load Balancer."
• Select "Application Load Balancer" and click "Create."

Step 5: Configure the Load Balancer

• Name your load balancer and select the scheme (internet-facing or internal).
• Select the desired VPC and add at least two subnets in different availability zones.
• Configure the listener to use HTTP and HTTPS.

Step 6: Register Targets

• Add the instances or other targets that you want to route traffic to. Ensure that the application on the targets listens on port 8080.

Step 7: Configure Security Settings for SSL (for HTTPS only)

If you're using HTTPS, you will need to configure SSL to ensure secure communication. Follow these steps:

1. Select a Listener: In the "Listeners" section, choose HTTPS as the protocol.
2. Choose or Upload a Certificate: You will need an SSL certificate to enable HTTPS. Select an existing certificate from AWS Certificate Manager (ACM) or upload a new one. If you don't have a certificate, you can request one through ACM.
   • To use an existing certificate, choose it from the dropdown menu.
   • To upload a new certificate, click on "Upload a certificate to AWS Identity and Access Management (IAM)" and follow the instructions.
   • To request a new certificate, go to AWS Certificate Manager, click on "Request a certificate," and follow the instructions. Once approved, the certificate will be available to choose in the load balancer configuration.
3. Configure Cipher and Policy: Select a pre-defined security policy or customize the SSL ciphers and protocols according to your security requirements. AWS provides recommended policies that meet various compliance requirements.
4. Configure Default Action: Set the default action to forward requests to the target group that you've configured to listen on port 8080.

By configuring SSL at the load balancer level, you ensure that all communication between clients and the load balancer is encrypted, providing an additional layer of security.

Note:

Make sure that the targets are configured to listen on port 8080, as the load balancer will be forwarding the HTTPS requests to this port. The SSL termination will be handled at the load balancer level, so the targets will receive unencrypted traffic on port 8080.

Step 8: Configure Listener Rules (Optional)

• You can add rules to forward HTTP requests to HTTPS if desired.
• Configure actions to forward to the target group created in Step 6.

Step 9: Review and Create

• Review your configurations and click "Create."

Step 10: Adjust Security Group Rules

• Configure security group rules to allow traffic on HTTP (port 80) and HTTPS (port 443) if using both protocols.

Step 11: Configure DNS

• Update your DNS records to point to the ALB's DNS name.

Conclusion

By configuring the Application Load Balancer to forward HTTP/HTTPS requests to targets on port 8080, you can ensure proper routing and security for your applications. Make sure your application within the target instances is set to listen on port 8080, as the ALB will be forwarding the traffic to this specific port. The benefits of SSL termination and the efficiency of the ALB remain intact with this configuration, providing a robust solution for managing client requests.

Note: If you are exclusively using HTTPS for secure communication, remember to handle the SSL termination at the ALB as explained in the previous instructions. If you're supporting both HTTP and HTTPS, consider implementing redirection from HTTP to HTTPS for increased security.