Local-exec provisioner in Terraform - Step-by-Step Execution

Process Flow - Local-exec provisioner

Terraform plan starts

↓

Resource created

↓

Local-exec provisioner triggers

↓

Runs local command/script

↓

Command success?

No→Error stops apply

Yes↓

Terraform apply continues/completes

Terraform creates a resource, then runs a local command on your machine using local-exec provisioner. If the command fails, apply stops.

Execution Sample

Terraform

resource "null_resource" "example" {
  provisioner "local-exec" {
    command = "echo Hello from local-exec"
  }
}

Creates a dummy resource and runs a local shell command printing a message on your machine.

Process Table

Step	Action	Resource State	Provisioner Command	Command Result	Next Step
1	Start terraform apply	No resource	N/A	N/A	Create resource
2	Create null_resource.example	Resource created	N/A	N/A	Run local-exec provisioner
3	Run local-exec command	Resource created	echo Hello from local-exec	Hello from local-exec printed	Check command success
4	Check command success	Resource created	N/A	Success	Complete apply
5	Terraform apply completes	Resource created	N/A	N/A	End

💡 Local-exec command succeeded, so terraform apply completes successfully.

Status Tracker

Variable	Start	After Step 2	After Step 3	Final
Resource State	No resource	Resource created	Resource created	Resource created
Provisioner Command	N/A	N/A	echo Hello from local-exec	N/A
Command Result	N/A	N/A	Hello from local-exec printed	Success

Key Moments - 3 Insights

Why does terraform stop if the local-exec command fails?

Terraform treats the local-exec provisioner as part of resource creation. If the command fails (see step 4 in execution_table), terraform stops to avoid inconsistent state.

Does the local-exec command run on the cloud resource?

No, local-exec runs on your local machine where terraform runs, not on the cloud resource itself (step 3 in execution_table).

Can local-exec provisioner access resource attributes?

Yes, you can use resource attributes in the command string, but the command still runs locally (noted in step 3).

Visual Quiz - 3 Questions

Look at the execution_table, what is the resource state after step 2?

A Resource created

B No resource

C Resource deleted

D Resource failed

💡 Hint

Check the 'Resource State' column at step 2 in execution_table.

At which step does the local-exec command run?

A Step 1

B Step 2

C Step 3

D Step 5

💡 Hint

Look for 'Run local-exec command' in the 'Action' column in execution_table.

If the local-exec command fails, what happens to terraform apply?

A It retries the command infinitely

B It stops with an error

C It continues normally

D It ignores the failure and completes

💡 Hint

Refer to the concept_flow and key_moments about command failure stopping apply.

Concept Snapshot

Local-exec provisioner runs a command on your local machine after resource creation.
Syntax: provisioner "local-exec" { command = "your-command" }
Runs during terraform apply.
If command fails, terraform apply stops.
Useful for local scripts or notifications.

Full Transcript

The local-exec provisioner in terraform runs a command on your local machine after a resource is created. The flow starts with terraform creating the resource, then triggering the local-exec provisioner to run the specified command. If the command succeeds, terraform continues and completes the apply. If it fails, terraform stops to avoid inconsistent state. The command runs locally, not on the cloud resource. You can use resource attributes in the command string. This provisioner is useful for running local scripts or notifications during terraform apply.