How to Import an Google Compute Cloud Router into Terraform

Import Google Compute Cloud Router with Terraback (recommended)

Terraback reverse-engineers your live infrastructure: it reads the Compute Engine resource with read-only credentials, generates the HCL, and produces the exact import block. Two commands take you from a live Google Compute Cloud Router to managed Terraform.

terraback scan all gcp --project my-gcp-project

terraback gcp 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 = google_compute_router.prod
  id = "projects/my-project/regions/us-central1/routers/prod-router"
}

Example google_compute_router configuration

Here is a realistic Google Compute Cloud Router block. Terraback generates a fuller version from your actual resource attributes; this is a minimal, valid starting point.

resource "google_compute_router" "prod" {
  name    = "prod-router"
  region  = "us-central1"
  network = "projects/my-project/global/networks/prod-vpc"

  bgp {
    asn            = 64514
    advertise_mode = "DEFAULT"
  }
}

Gotchas when importing a Google Compute Cloud Router

• Cloud Routers are regional; the import path uses a regions/<region> segment.
• A Cloud NAT configuration is the separate google_compute_router_nat resource attached to this router, not part of it.
• BGP peers and interfaces for Cloud Interconnect or VPN are separate google_compute_router_peer and google_compute_router_interface resources.
• The bgp.asn must match the live value; changing it disrupts any dynamic routing the router provides.

Doing it manually with terraform import

The native approach is to write the google_compute_router block by hand, then run terraform import google_compute_router.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 Google Cloud resources