Optimizing Resource Migration in Terraform using Config-Driven Automation

Since the release of Terraform 1.5 in June 2023, developers have been excited about the new features added to the popular HashiCorp’s IaC tool. One of the standout additions is the ability to automatically generate Terraform configurations using a new argument in the existing import command. This enhancement simplifies the process of importing external resources into Terraform management and eliminates the need for manual configuration mapping, providing a more scalable and efficient solution.

Terraform import

Although Terraform import is not a new concept, it has significantly improved with the latest update. The initial version of the import command required developers to manually map existing resource configurations without generating any HashiCorp Configuration Language (HCL) code. Additionally, it only supported importing one resource at a time, which posed limitations.

Let’s consider a scenario where we aim to bring several resources, such as a resource group, virtual network, subnet, public IP address, and virtual network gateway, under Terraform management. Previously, we would have had to manually write the entire Terraform configuration for each resource and map them individually.