When importing existing infrastructure into Terraform, should Terraform configuration be written before performing the import?

When importing existing infrastructure into Terraform, should Terraform configuration be written before performing the import?

• A. Infrastructure can be imported without corresponding Terraform code
• B. Terraform will generate the corresponding configuration files for you
• C. You should write after the next terraform import
• D. Terraform configuration should be written before terraform import is executed

Answer: (D)

Before importing, have Terraform configuration written that describes the resources you intend to manage. Importing updates Terraform’s state to reflect existing real resources, but it does not generate or modify your code. Without a matching resource block in the configuration, there’s nothing for Terraform to attach the imported resource to, leaving state entries that you cannot manage with code. By defining the resource blocks first, you ensure that the import maps the actual infrastructure to the correct pieces of your configuration, so you can plan, adjust attributes, and apply changes to bring the real resources in line with your desired state. For example, define the resource for the AWS resource you’re bringing in, then run the import command to connect the existing resource to that block. After import, you can refine the configuration (tags, settings) and run plan and apply to lock in the intended configuration.

Before importing, have Terraform configuration written that describes the resources you intend to manage. Importing updates Terraform’s state to reflect existing real resources, but it does not generate or modify your code. Without a matching resource block in the configuration, there’s nothing for Terraform to attach the imported resource to, leaving state entries that you cannot manage with code. By defining the resource blocks first, you ensure that the import maps the actual infrastructure to the correct pieces of your configuration, so you can plan, adjust attributes, and apply changes to bring the real resources in line with your desired state. For example, define the resource for the AWS resource you’re bringing in, then run the import command to connect the existing resource to that block. After import, you can refine the configuration (tags, settings) and run plan and apply to lock in the intended configuration.