How to Enable SSL/TLS Certificates on AWS Load Balancers

SSL/TLS encryption ensures secure communication between clients and AWS Load Balancers. In this guide, we'll walk through how to enable SSL/TLS certificates on both Application Load Balancers (ALB) and Network Load Balancers (NLB).

🔹 Enabling SSL/TLS on an Application Load Balancer (ALB)

To configure SSL/TLS on an ALB, follow these steps:

1. Add an HTTPS Listener

• Navigate to your ALB in the AWS Console.
• Click "Listeners", then "Add listener".
• Set Protocol to HTTPS and Port to 443.

2. Forward Traffic to a Target Group

• Define where the traffic should be forwarded.
• Choose a target group that contains your backend EC2 instances.

3. Configure Secure Listener Settings

• Set an SSL Security Policy:
  • Default: Uses the latest secure encryption standards.
  • Custom: Choose older SSL/TLS versions if compatibility with legacy clients is needed.

4. Choose an SSL Certificate Source

• AWS Certificate Manager (ACM) (Recommended)
• IAM Certificate Store (Not recommended for domain-based certificates)
• Import a certificate manually by providing:
  • Private Key
  • Certificate Body
  • Certificate Chain

5. Save the Listener Configuration

Once configured, your ALB will accept HTTPS traffic and encrypt it using SSL/TLS.