## GCSからLocalにもってくる
# backupをとる(optional)
$ terraform state pull >> terraform.tfstate.backup
# ======
# terraform {
# # backend "gcs" {
# # bucket = "dev-tfstate"
# # }
# ...
# }
# ======
# bucketセクションをコメントアウトしてplanを実行すると怒られる．initが必要．
$ terraform plan
╷
│ Error: Backend initialization required, please run "terraform init"
│
│ Reason: Unsetting the previously set backend "gcs"
│
│ The "backend" is the interface that Terraform uses to store state,
│ perform operations, etc. If this message is showing up, it means that the
│ Terraform configuration you're using is using a custom configuration for
│ the Terraform backend.
│
│ Changes to backend configurations require reinitialization. This allows
│ Terraform to set up the new configuration, copy existing state, etc. Please run
│ "terraform init" with either the "-reconfigure" or "-migrate-state" flags to
│ use the current configuration.
│
│ If the change reason above is incorrect, please verify your configuration
│ hasn't changed and try again. At this point, no changes to your existing
│ configuration or state have been made.
# migrateするためには -migrate-stateオプションが必要と言われる
$ terraform init
Initializing the backend...
╷
│ Error: Backend configuration changed
│
│ A change in the backend configuration has been detected, which may require migrating existing
│ state.
│
│ If you wish to attempt automatic migration of the state, use "terraform init -migrate-state".
│ If you wish to store the current configuration with no changes to the state, use "terraform
│ init -reconfigure".
╵
# -migrate-state オプションをつけると，gcsからlocalにstate backendを変更する旨の確認が出る．yesでlocalにstateが来る．
$ terraform init -migrate-state
Initializing the backend...
Terraform has detected you're unconfiguring your previously set "gcs" backend.
Do you want to copy existing state to the new backend?
Pre-existing state was found while migrating the previous "gcs" backend to the
newly configured "local" backend. No existing state was found in the newly
configured "local" backend. Do you want to copy this state to the new "local"
backend? Enter "yes" to copy and "no" to start with an empty state.
Enter a value: yes
Successfully unset the backend "gcs". Terraform will now operate locally.
Initializing provider plugins...
- Reusing previous version of jp7fkf.dev/dev/dev-terraform-provider from the dependency lock file
- Using previously-installed jp7fkf.dev/dev/dev-terraform-provider v0.0.1
Terraform has been successfully initialized!
You may now begin working with Terraform. Try running "terraform plan" to see
any changes that are required for your infrastructure. All Terraform commands
should now work.
If you ever set or change modules or backend configuration for Terraform,
rerun this command to reinitialize your working directory. If you forget, other
commands will detect it and remind you to do so if necessary.
# これでlocalにstate変更が完了
## LocalからGCSにもっていく
# backupとかは省略．概ね逆手順で実行できる．
# backendを記載する．
# ======
# terraform {
# backend "gcs" {
# bucket = "dev-tfstate"
# }
# ...
# }
# ======
# 同様に-migrate-steteを付与してinitをすると，localからgcsにbackendを変更する旨の確認が出る．yesでマイグレ．
$ terraform init -migrate-state
Initializing the backend...
Do you want to copy existing state to the new backend?
Pre-existing state was found while migrating the previous "local" backend to the
newly configured "gcs" backend. No existing state was found in the newly
configured "gcs" backend. Do you want to copy this state to the new "gcs"
backend? Enter "yes" to copy and "no" to start with an empty state.
Enter a value: yes
Successfully configured the backend "gcs"! Terraform will automatically
use this backend unless the backend configuration changes.
Initializing provider plugins...
- Reusing previous version of jp7fkf.dev/dev/dev-terraform-provider from the dependency lock file
- Using previously-installed jp7fkf.dev/dev/dev-terraform-provider v0.0.1
Terraform has been successfully initialized!
You may now begin working with Terraform. Try running "terraform plan" to see
any changes that are required for your infrastructure. All Terraform commands
should now work.
If you ever set or change modules or backend configuration for Terraform,
rerun this command to reinitialize your working directory. If you forget, other
commands will detect it and remind you to do so if necessary.