If you want to refactor your code without accidentally causing downtime, you’ll need to update the Terraform state accordingly. However, you should never update Terraform state files by hand! Instead, you have two options: do it manually by running terraform state mv commands, or do it automatically by adding a moved block to your code.

Let’s first look at the terraform state mv command, which has the following syntax:

terraform state mv

where ORIGINAL_REFERENCE is the reference expression to the resource as it is now and NEW_REFERENCE is the new location you want to move it to. For example, if you’re renaming an aws_security_group group from instance to cluster_instance, you could run the following: