Add port 9998 listener and target group for healthcheck

[pato-macrometa]

Overview

This PR adds a port 9998 listener and target group for health checks to the Banyan repository's Terraform configuration. These enhancements are designed to improve network health monitoring and align with Banyan's infrastructure standards.

Changes Made

1. AWS Load Balancer Target Group Configuration:

   • Added a new AWS Load Balancer Target Group aws_lb_target_group named target9998.
   • Configured with TCP protocol on port 9998, aligned with Banyan's requirement for specific port management.
   • Stickiness and health check features are configured to ensure robustness and reliability.

2. AWS Load Balancer Listener Configuration:

   • Established aws_lb_listener for the Load Balancer, using the same TCP protocol on port 9998.
   • Default action set to forward traffic to the newly created Target Group.

Alignment with Banyan Documentation

• The configuration is designed in accordance with Banyan's Access Tier architecture, ensuring that the Access Tier functions effectively as a reverse proxy on specified ports, which is essential for managing traffic in a Zero Trust environment (Banyan Security Documentation).
• The health check on port 9998 is crucial for determining the Netagent's ability to service traffic, a key aspect of Banyan's Netagent capabilities (Banyan Security Documentation).

Intent and Impact

• The intention is to leverage Banyan's advanced security functionalities to protect our cloud-native deployments.

[yoshiotu]

If I understand this correctly, it's adding one more listen port to the load balancer. Netagent's port 9998 health check should be called internally for the target group health check, but maybe it's not desirable to expose it publicly.