How to Import an AWS Load Balancer Listener into Terraform

Import AWS Load Balancer Listener 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 Listener 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_listener.https
  id = "arn:aws:elasticloadbalancing:us-east-1:123456789012:listener/app/web-alb/50dc6c495c0c9188/f2f7dc8efc522ab2"
}

Example aws_lb_listener configuration

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

resource "aws_lb_listener" "https" {
  load_balancer_arn = "arn:aws:elasticloadbalancing:us-east-1:123456789012:loadbalancer/app/web-alb/50dc6c495c0c9188"
  port              = 443
  protocol          = "HTTPS"
  ssl_policy        = "ELBSecurityPolicy-TLS13-1-2-2021-06"
  certificate_arn   = "arn:aws:acm:us-east-1:123456789012:certificate/12345678-1234-1234-1234-123456789012"

  default_action {
    type             = "forward"
    target_group_arn = "arn:aws:elasticloadbalancing:us-east-1:123456789012:targetgroup/web/73e2d6bc24d8a067"
  }
}

Gotchas when importing a AWS Load Balancer Listener

• Import by the listener ARN, not the load balancer ARN.
• Listener rules (aws_lb_listener_rule) beyond the default action are separate resources and are not imported with the listener.
• For HTTPS/TLS listeners with more than one certificate, the extra certificates import as aws_lb_listener_certificate resources.
• The default_action references a target group ARN or auth config; those referenced resources are managed separately.

Doing it manually with terraform import

The native approach is to write the aws_lb_listener block by hand, then run terraform import aws_lb_listener.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