How to Import an AWS EFS Mount Target into Terraform

Import AWS EFS Mount Target with Terraback (recommended)

Terraback reverse-engineers your live infrastructure: it reads the Amazon EFS resource with read-only credentials, generates the HCL, and produces the exact import block. Two commands take you from a live AWS EFS Mount Target 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_efs_mount_target.az_a
  id = "fsmt-0a1b2c3d4e5f6a7b8"
}

Example aws_efs_mount_target configuration

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

resource "aws_efs_mount_target" "az_a" {
  file_system_id  = "fs-0a1b2c3d4e5f6a7b8"
  subnet_id       = "subnet-0aa1b2c3d4e5f6a7b"
  security_groups = ["sg-0123456789abcdef0"]
}

Gotchas when importing a AWS EFS Mount Target

• Import by the fsmt- mount target ID, not the fs- file system ID.
• There is one mount target per subnet (per Availability Zone); a multi-AZ file system has multiple aws_efs_mount_target resources to import.
• subnet_id is immutable; you cannot move a mount target between subnets, so a changed value forces replacement.
• If security_groups is omitted, AWS attaches the VPC default security group; set it explicitly or Terraform may show a diff after import.

Doing it manually with terraform import

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