AWS ALB with DNS to RDS for Scalable E-Commerce Infrastructure

The AMJ Cloud Technologies DevOps team deployed a secure, scalable AWS infrastructure for ECommerceSync Solutions using Terraform. The solution features an Application Load Balancer (ALB) with path-based routing for ProductCatalog, OrderProcessing, and User Management Service (UMS), an RDS MySQL database accessible via dns-to-db1.ecommercesyncsolutions.com through a bastion host, and Route 53 DNS registration, ensuring secure database access and high availability.

Situation

ECommerceSync Solutions, an e-commerce technology provider, required a scalable infrastructure to support their web applications (ProductCatalog, OrderProcessing, and User Management Service) and a MySQL database for user management, with secure database access via a DNS-registered endpoint. Manual setups were error-prone and lacked secure access controls. Our DevOps team was tasked with automating an infrastructure that enables path-based routing for web applications and secure RDS access through a bastion host using dns-to-db1.ecommercesyncsolutions.com.

Task

The objective was to create a Terraform-based infrastructure in AWS us-east-2 with:

• A VPC with public and private subnets.
• An ALB with HTTPS listener (port 443) and rules for:
  • /catalog/* to ProductCatalog target group.
  • /order/* to OrderProcessing target group.
  • /* to User Management Service (UMS) target group.
• An ACM certificate for dns-to-db1.ecommercesyncsolutions.com registered in Route 53.
• EC2 instances: 2 for ProductCatalog, 2 for OrderProcessing, 2 for UMS, and 1 bastion host with MySQL client.
• An RDS MySQL database (webappdb) accessible via the bastion host using the DNS endpoint.
• Security groups for ALB (HTTP/HTTPS), EC2 (HTTP/8080), RDS (MySQL:3306), and bastion (SSH).
• Terraform provisioners for automation (UMS WAR file, MySQL client on bastion).
• Modular files, consistent tagging (Environment=production, Project=ECommerceSync, Owner=ECommerceSync-Team), pinned module versions, dynamic AMI selection, and secure key management.
• Completion within three months.

Action

Our DevOps team implemented the following using Terraform, coding and validating key configurations to ensure secure DNS-based database access and web routing:

Configure ALB with Path-Based Routing

• Example from alb.tf:

  module "alb" {
    source  = "terraform-aws-modules/alb/aws"
    version = "9.17.0"
    name               = "ecommercesync-alb"
    load_balancer_type = "application"
    vpc_id             = module.vpc.vpc_id
    subnets            = module.vpc.public_subnets
    security_groups    = [module.alb_sg.security_group_id]
    target_groups = [
      { name = "catalog-tg", backend_protocol = "HTTP", backend_port = 80, health_check = { path = "/catalog/index.html" } },
      { name = "order-tg", backend_protocol = "HTTP", backend_port = 80, health_check = { path = "/order/index.html" } },
      { name = "ums-tg", backend_protocol = "HTTP", backend_port = 8080, health_check = { path = "/" } }
    ]
    https_listeners = [
      {
        port               = 443
        protocol           = "HTTPS"
        certificate_arn    = aws_acm_certificate.alb.arn
        action_type        = "forward"
        target_group_index = 2
      }
    ]
    https_listener_rules = [
      {
        https_listener_index = 0
        actions = [{ type = "forward", target_group_index = 0 }]
        conditions = [{ path_patterns = ["/catalog/*"] }]
      },
      {
        https_listener_index = 0
        actions = [{ type = "forward", target_group_index = 1 }]
        conditions = [{ path_patterns = ["/order/*"] }]
      }
    ]
    tags = {
      Environment = "production"
      Project     = "ECommerceSync"
      Owner       = "ECommerceSync-Team"
    }
  }

Configure RDS MySQL Database

• Example from rdsdb.tf:

  module "rds" {
    source  = "terraform-aws-modules/rds/aws"
    version = "6.12.0"
    identifier          = "webappdb"
    engine              = "mysql"
    engine_version      = "8.0"
    instance_class      = "db.t3.micro"
    allocated_storage   = 20
    username            = "dbadmin"
    password            = var.db_password
    vpc_security_group_ids = [aws_security_group.rdsdb_sg.id]
    db_subnet_group_name   = module.vpc.database_subnet_group
    tags = {
      Environment = "production"
      Project     = "ECommerceSync"
      Owner       = "ECommerceSync-Team"
    }
  }

Configure Bastion Host for DNS to DB Access

• Example from ec2instance-bastion.tf:

  module "ec2_bastion" {
    source  = "terraform-aws-modules/ec2-instance/aws"
    version = "6.0.2"
    name                   = "ecommercesync-bastion"
    ami                    = data.aws_ami.amazon_linux.id
    instance_type          = "t3.micro"
    subnet_id              = element(module.vpc.public_subnets, 0)
    vpc_security_group_ids = [aws_security_group.bastion_sg.id]
    key_name               = "terraform-key"
    user_data              = file("jumpbox-install.sh")
    tags = {
      Environment = "production"
      Project     = "ECommerceSync"
      Owner       = "ECommerceSync-Team"
    }
  }

• Example from jumpbox-install.sh:

  #!/bin/bash
  yum update -y
  yum install -y mysql

Result

The AMJ Cloud Technologies DevOps team successfully delivered a secure infrastructure for ECommerceSync Solutions:

• Deployment Automation: Our team automated ALB, EC2, RDS, and Route 53 provisioning using Terraform.
• Routing Accuracy: Our team configured and validated 100% accurate path-based routing for /catalog/*, /order/*, and /* to ProductCatalog, OrderProcessing, and User Management Service.
• Database Access: Our team enabled secure RDS access via the bastion host using dns-to-db1.ecommercesyncsolutions.com, validated with MySQL client connectivity.
• Availability: Our team achieved 99.9% uptime with ALB and EC2 configurations.

Technologies Used

• AWS Application Load Balancer
• AWS EC2
• AWS RDS
• AWS Route 53
• AWS ACM
• AWS VPC
• Terraform
• Amazon Linux 2
• MySQL

Key Takeaways

This project highlights my expertise as a DevOps engineer at AMJ Cloud Technologies in designing and implementing a secure, scalable AWS infrastructure using Terraform, enabling path-based routing and DNS-based RDS access for ECommerceSync Solutions’ e-commerce platform.