How to Import an AWS Load Balancer Target Group into Terraform

Import AWS Load Balancer Target Group with Terraback (recommended)

Terraback reverse-engineers your live infrastructure: it reads the Elastic Load Balancing resource with read-only credentials, generates the HCL, and produces the exact import block. Two commands take you from a live AWS Load Balancer Target Group to managed Terraform.

terraback scan all aws --region us-east-1

terraback aws import --method bulk

The Terraform import block

Terraback emits a Terraform 1.5+ import block like the one below. Because the block lives in your configuration, the import is reviewable in a pull request and repeatable across environments.

import {
  to = aws_lb_target_group.web
  id = "arn:aws:elasticloadbalancing:us-east-1:123456789012:targetgroup/web/73e2d6bc24d8a067"
}

Example aws_lb_target_group configuration

Here is a realistic AWS Load Balancer Target Group block. Terraback generates a fuller version from your actual resource attributes; this is a minimal, valid starting point.

resource "aws_lb_target_group" "web" {
  name        = "web"
  port        = 80
  protocol    = "HTTP"
  vpc_id      = "vpc-0a1b2c3d4e5f6a7b8"
  target_type = "instance"

  health_check {
    path                = "/health"
    healthy_threshold   = 2
    unhealthy_threshold = 2
  }
}

Gotchas when importing a AWS Load Balancer Target Group

• Import by the target group ARN, not the name.
• Target attachments (aws_lb_target_group_attachment) registering instances, IPs, or Lambda functions are separate resources and are not imported.
• target_type (instance, ip, lambda, alb) is immutable; a mismatch forces replacement.
• port and protocol are ignored for lambda target types, so reconcile the type before adding those attributes.

Doing it manually with terraform import

The native approach is to write the aws_lb_target_group block by hand, then run terraform import aws_lb_target_group.example <import-id> for every resource, one at a time. That works for a handful of resources, but it does not scale: you author all the HCL yourself and repeat the command for each item. Terraback generates the HCL and the import blocks for your whole account in one pass.

Import other AWS resources