Step-01: Introduction

Step-02: c5-04-securitygroup-privatesg.tf

# Before  ingress_cidr_blocks = [module.vpc.vpc_cidr_block]# After  ingress_cidr_blocks = ["0.0.0.0/0"]# Required for NLB

Step-03: c10-01-NLB-network-loadbalancer-variables.tf

Step-04: c10-02-NLB-network-loadbalancer.tf

# Terraform AWS Network Load Balancer (NLB)module"nlb" {  source  ="terraform-aws-modules/alb/aws"  version ="9.4.0"  name_prefix ="mynlb-"  load_balancer_type               ="network"  vpc_id                           = module.vpc.vpc_id  dns_record_client_routing_policy ="availability_zone_affinity"  security_groups = [module.loadbalancer_sg.security_group_id]# https://github.com/hashicorp/terraform-provider-aws/issues/17281  subnets = module.vpc.public_subnets# For example only  enable_deletion_protection = false# Listeners  listeners = {# Listener-1: TCP Listenermy-tcp = {      port     = 80      protocol ="TCP"      forward = {        target_group_key ="mytg1"      }    }# End Listener-1: TCP Listener# Listener-2: TLS Listener (SSL)my-tls = {      port            = 443      protocol        ="TLS"      certificate_arn = module.acm.acm_certificate_arn      forward = {        target_group_key ="mytg1"      }    }# End Listener-2: TLS Listener (SSL)  }# End Listeners Block# Target Groups  target_groups = {# Target Group-1: mytg1    mytg1 = {      create_attachment = false                name_prefix          ="mytg1-"      protocol             ="TCP"      port                 = 80      target_type          ="instance"      deregistration_delay = 10      health_check = {        enabled             = true        interval            = 30        path                ="/app1/index.html"        port                ="traffic-port"        healthy_threshold   = 3        unhealthy_threshold = 3        timeout             = 6      }# End Health Check Block    }# End Target Group-1: mytg1  }  tags =local.common_tags}# End NLB Module

Step-05: c10-03-NLB-network-loadbalancer-outputs.tf

# Terraform AWS Network Load Balancer (NLB) Outputs################################################################################# Load Balancer################################################################################output"id" {  description ="The ID and ARN of the load balancer we created"  value       = module.nlb.id}output"arn" {  description ="The ID and ARN of the load balancer we created"  value       = module.nlb.arn}output"arn_suffix" {  description ="ARN suffix of our load balancer - can be used with CloudWatch"  value       = module.nlb.arn_suffix}output"dns_name" {  description ="The DNS name of the load balancer"  value       = module.nlb.dns_name}output"zone_id" {  description ="The zone_id of the load balancer to assist with creating DNS records"  value       = module.nlb.zone_id}################################################################################# Listener(s)################################################################################output"listeners" {  description ="Map of listeners created and their attributes"  value       = module.nlb.listeners}output"listener_rules" {  description ="Map of listeners rules created and their attributes"  value       = module.nlb.listener_rules}################################################################################# Target Group(s)################################################################################output"target_groups" {  description ="Map of target groups created and their attributes"  value       = module.nlb.target_groups}################################################################################# Security Group################################################################################output"security_group_arn" {  description ="Amazon Resource Name (ARN) of the security group"  value       = module.nlb.security_group_arn}output"security_group_id" {  description ="ID of the security group"  value       = module.nlb.security_group_id}################################################################################# Route53 Record(s)################################################################################output"route53_records" {  description ="The Route53 records created and attached to the load balancer"  value       = module.nlb.route53_records}

Step-06: c12-route53-dnsregistration.tf

# DNS Registrationresource"aws_route53_record""apps_dns" {  zone_id = data.aws_route53_zone.mydomain.zone_id   name    ="nlb1.devopsincloud.com"  type    ="A"  alias {    name                   = module.nlb.lb_dns_name    zone_id                = module.nlb.lb_zone_id    evaluate_target_health = true  }  }

Step-07: c13-03-autoscaling-resource.tf

# Before  target_group_arns = [module.alb.target_groups["mytg1"].arn]# After  target_group_arns = [module.nlb.target_groups["mytg1"].arn]

Step-08: c13-06-autoscaling-ttsp.tf

# TTS - Scaling Policy-2: Based on ALB Target Requests# THIS POLICY IS SPECIFIC TO ALB and NOT APPLICABLE TO NLB/*resource "aws_autoscaling_policy" "alb_target_requests_greater_than_yy" {  name                   = "alb-target-requests-greater-than-yy"  policy_type = "TargetTrackingScaling" # Important Note: The policy type, either "SimpleScaling", "StepScaling" or "TargetTrackingScaling". If this value isn't provided, AWS will default to "SimpleScaling."  autoscaling_group_name = aws_autoscaling_group.my_asg.id  estimated_instance_warmup = 120 # defaults to ASG default cooldown 300 seconds if not set  # Number of requests > 10 completed per target in an Application Load Balancer target group.  target_tracking_configuration {    predefined_metric_specification {      predefined_metric_type = "ALBRequestCountPerTarget"      resource_label =  "${module.alb.lb_arn_suffix}/${module.alb.target_group_arn_suffixes[0]}"    }    target_value = 10.0  }}*/

Step-09: Execute Terraform Commands

# Terraform Initializeterraform init# Terrafom Validateterraform validate# Terraform Planterraform plan# Terraform Applyterraform apply -auto-approve

Step-10: Verify the AWS resources created

# Access and Test with Port 80 - TCP Listenerhttp://nlb.devopsincloud.comhttp://nlb.devopsincloud.com/app1/index.htmlhttp://nlb.devopsincloud.com/app1/metadata.html# Access and Test with Port 443 - TLS Listenerhttps://nlb.devopsincloud.comhttps://nlb.devopsincloud.com/app1/index.htmlhttps://nlb.devopsincloud.com/app1/metadata.html

Step-11: Clean-Up

# Terraform Destroyterraform destroy -auto-approve# Clean-Up Filesrm -rf .terraform*rm -rf terraform.tfstate*

References