The ELB could not be updated due to the following error: Primary taskset target group is not behind any rule for listener

I try AWS CodeDeploy for ECS Blue/Green Deployment.

I use terraform to definition codedeploy.

this below my terraform code.

resource "aws_codedeploy_app" "ecs_dev" {
  compute_platform = "ECS"
  name             = "code-deploy-ecs-${local.env}"
}

resource "aws_codedeploy_deployment_group" "ecs_dev" {
  app_name               = aws_codedeploy_app.ecs_dev.name
  deployment_config_name = "CodeDeployDefault.ECSAllAtOnce"
  deployment_group_name  = "ecs-dev"
  service_role_arn       = aws_iam_role.code_deploy_ecs.arn

  auto_rollback_configuration {
    enabled = true
    events  = ["DEPLOYMENT_FAILURE"]
  }

  deployment_style {
    deployment_option = "WITH_TRAFFIC_CONTROL"
    deployment_type   = "BLUE_GREEN"
  }

  blue_green_deployment_config {

    deployment_ready_option {
      action_on_timeout = "CONTINUE_DEPLOYMENT"
    }

    terminate_blue_instances_on_deployment_success {
      action                           = "TERMINATE"
      termination_wait_time_in_minutes = 10
    }

  }

  ecs_service {
    cluster_name = "cluster-name"
    service_name = "ecs-dev"
  }

  load_balancer_info {
    target_group_pair_info {

      prod_traffic_route {
        listener_arns = "listener_arn" # created from aws console
      }

      # green
      target_group {
        name = "green-target-group" # created from aws console
      }

      # blue
      target_group {
        name = aws_lb_target_group.blue.name
      }
    }
  }
}

resource "aws_lb_target_group" "blue" {
  name        = "blue-target-group"
  port        = 80
  protocol    = "HTTP"
  vpc_id      = "ecs-vpc"
  target_type = "instance"

  health_check {
    interval            = 30
    timeout             = 5
    healthy_threshold   = 5
    unhealthy_threshold = 2
    protocol            = "HTTP"
    port                = "traffic-port"
    path                = each.value.health_check_path
  }
}

When I successfully configured CodeDeploy itself and deployed a new task in ECS, the following error occurred.

The ELB could not be updated due to the following error: Primary taskset target group is not behind any rule for listener

What this means is not clear to me. If there is any other information you would like to know, I will provide it.

Thank you for your time.

The target group for the ECS blue/green deployment should be attached to some load balancer, so add a listener and rule for the target group. In my case, I have added the listener with a fixed port by data and attach the target group by add a rule.

# Code Deploy

resource "aws_codedeploy_app" "new" {
  compute_platform = "ECS"
  name             = local.name_code_deploy
}

resource "aws_codedeploy_deployment_group" "new" {
  app_name               = aws_codedeploy_app.new.name
  deployment_group_name  = local.name_deployment_group
  deployment_config_name = "CodeDeployDefault.ECSAllAtOnce"
  service_role_arn       = "arn:${var.partition}:iam::${var.account}:role/AWSCodeDeployRoleForECS"

  auto_rollback_configuration {
    enabled = true
    events  = ["DEPLOYMENT_FAILURE"]
  }

  blue_green_deployment_config {
    deployment_ready_option {
      action_on_timeout = "CONTINUE_DEPLOYMENT"
    }
    terminate_blue_instances_on_deployment_success {
      action                           = "TERMINATE"
      termination_wait_time_in_minutes = 0
    }
  }

  deployment_style {
    deployment_option = "WITH_TRAFFIC_CONTROL"
    deployment_type   = "BLUE_GREEN"
  }

  ecs_service {
    cluster_name = data.aws_ecs_cluster.default.cluster_name
    service_name = aws_ecs_service.new.name
  }

  load_balancer_info {
    target_group_pair_info {
      prod_traffic_route {
        listener_arns = [data.aws_lb_listener.default.arn]
      }
      target_group {
        name = aws_lb_target_group.blue.name
      }
      target_group {
        name = aws_lb_target_group.green.name
      }
    }
  }
}

# ECS Service 

resource "aws_ecs_service" "new" {
  name          = local.name_ecs_service
  cluster       = data.aws_ecs_cluster.default.id
  desired_count = var.service_count

  deployment_controller {
    type = "CODE_DEPLOY"
  }

  enable_ecs_managed_tags           = true
  enable_execute_command            = true
  launch_type                       = "FARGATE"
  scheduling_strategy               = "REPLICA"
  health_check_grace_period_seconds = 120

  load_balancer {
    target_group_arn = aws_lb_target_group.green.arn # Blue/Green Check!
    container_name   = local.name_ecs_container
    container_port   = var.task_port
  }

  network_configuration {
    subnets = var.subnets_web
    security_groups = [
      aws_security_group.ecs_service.id
    ]
    assign_public_ip = false
  }
  propagate_tags  = "SERVICE"
  task_definition = aws_ecs_task_definition.new.family

  lifecycle {
    ignore_changes = [
      task_definition,
      desired_count
    ]
  }
}

# ELB Listener

resource "aws_lb_target_group" "blue" {
  name        = local.name_tg_blue
  port        = var.task_port
  protocol    = "HTTP"
  target_type = "ip"
  vpc_id      = data.aws_vpc.default.id

  health_check {
    enabled             = true
    path                = var.alb_health_path
    healthy_threshold   = 2
    unhealthy_threshold = 3
  }
}

resource "aws_lb_target_group" "green" {
  name        = local.name_tg_green
  port        = var.task_port
  protocol    = "HTTP"
  target_type = "ip"
  vpc_id      = data.aws_vpc.default.id

  health_check {
    enabled             = true
    path                = var.alb_health_path
    healthy_threshold   = 2
    unhealthy_threshold = 3
  }
}

resource "aws_lb_listener_rule" "new" {
  listener_arn = data.aws_lb_listener.default.arn

  action {
    type             = "forward"
    target_group_arn = aws_lb_target_group.green.arn # Blue/Green Check!
  }

  condition {
    host_header {
      values = var.alb_domain
    }
  }
}

# Other resources

data "aws_vpc" "default" {
  id = var.vpc_id
}

data "aws_ecs_cluster" "default" {
  cluster_name = var.cluster_name
}

data "aws_lb" "default" {
  name = var.alb_front_name
}

data "aws_lb_listener" "default" {
  load_balancer_arn = data.aws_lb.default.arn
  port = var.listener_port
}