Terraform import command - Step-by-Step Execution

Process Flow - Terraform import command

Start: Existing Resource

↓

Run terraform import

↓

Terraform maps resource to state

↓

State file updated

↓

Terraform can now manage resource

↓

End

The terraform import command links an existing resource to Terraform's state, allowing Terraform to manage it.

Execution Sample

Terraform

terraform import aws_instance.example i-1234567890abcdef0

Imports an existing AWS EC2 instance with ID i-1234567890abcdef0 into Terraform state as aws_instance.example.

Process Table

Step	Action	Input	Terraform State Change	Result
1	Identify existing resource	AWS EC2 instance ID i-1234567890abcdef0	No change yet	Ready to import
2	Run terraform import command	terraform import aws_instance.example i-1234567890abcdef0	Maps aws_instance.example to resource ID	State file updated with resource
3	Terraform state updated	Resource linked in state file	State file now tracks aws_instance.example	Terraform can manage resource
4	Verify import	terraform plan	Checks resource matches configuration	No changes if config matches
5	Exit	Import complete	State file updated	Terraform manages existing resource

💡 Import completes when resource is linked in Terraform state and ready for management.

Status Tracker

Variable	Start	After Step 2	After Step 3	Final
Terraform State	Empty or without resource	Resource aws_instance.example mapped	State file updated with resource details	State tracks aws_instance.example

Key Moments - 3 Insights

Why doesn't terraform import create a resource?

Terraform import only links existing resources to the state; it does not create or modify resources. See execution_table step 2 where the resource is mapped but not created.

What happens if the Terraform configuration does not match the imported resource?

Terraform plan after import (step 4) will show differences and may propose changes to match the configuration.

Does terraform import update the configuration files?

No, terraform import only updates the state file. Configuration files must be written manually to match the imported resource.

Visual Quiz - 3 Questions

Look at the execution_table, at which step is the Terraform state file updated?

A Step 1

B Step 4

C Step 2

D Step 5

💡 Hint

Check the 'Terraform State Change' column in execution_table rows.

According to variable_tracker, what is the state of Terraform State after step 3?

A State file updated with resource details

B Resource aws_instance.example mapped

C Empty or without resource

D State tracks aws_instance.example

💡 Hint

Look at the 'After Step 3' column for Terraform State in variable_tracker.

If the configuration file does not match the imported resource, what will terraform plan show?

A No changes

B Proposed changes to match configuration

C Error and stops

D Deletes the resource

💡 Hint

Refer to key_moments about what happens after import when config differs.

Concept Snapshot

terraform import <resource> <id>

Links an existing resource to Terraform state.
Does NOT create or modify resources.
Updates state file only.
Configuration files must match resource manually.
Run terraform plan to verify after import.

Full Transcript

The terraform import command is used to bring an existing cloud resource under Terraform management by linking it to the Terraform state file. It does not create or change the resource itself. The process starts by identifying the existing resource, then running the import command with the resource address and ID. Terraform updates its state file to track the resource. After import, running terraform plan helps verify if the configuration matches the imported resource. If there are differences, Terraform will propose changes. Import only affects the state file; configuration files must be written manually to reflect the resource. This allows Terraform to manage resources created outside Terraform.