Failed to terraform apply with tfplan generated by tfmigrate plan --out=tfplan in Terraform 1.1 about tfmigrate HOT 1 CLOSED

After debugging, I found that the tfmigrate plan --out=tfplan option was based on a bug prior to Terraform 1.1.

Since terraform state push increments the serial of tfstate, a saved plan file in tfmigrate plan phase should not be able to terraform apply. However, prior to Terraform 1.1, there was no proper validation and terraform apply allows a such case incorrectly. Starting from Terraform 1.1, it now rejects the plan as stale, which seems to be a correct behavior.

That is, the tfmigrate plan --out=tfplan option doesn't work with Terraform 1.1 or later. There is no way to do this.

Fortunately, Terraform 1.1 added a new moved block feature, so some use-cases could be covered by the moved block.
https://www.hashicorp.com/blog/terraform-1-1-improves-refactoring-and-the-cloud-cli-experience

So, I decided to deprecate the tfmigrate plan --out=tfplan option without replacement and it will be removed in a future release.

from tfmigrate.