Use Terraform outside the core workflow →easyMultiple ChoiceObjective-mapped

TF-004 Use Terraform outside the core workflow Practice Question

Exhibit

resource "aws_instance" "web" {
  ami           = "ami-0c55b159cbfafe1f0"
  instance_type = "t2.micro"
  provisioner "local-exec" {
    command = "echo ${aws_instance.web.private_ip} > /tmp/ip.txt"
  }
}

Refer to the exhibit. A team deploys this configuration. They run 'terraform apply' once and the instance is created. Later, they modify the instance type and run 'terraform apply' again. They notice the provisioner does not run on the second apply. Why?

⚠ Common exam trap

Terraform often tests the misconception that provisioners run on every 'terraform apply' regardless of the resource lifecycle, leading candidates to overlook the creation-only default behavior.

Answer choices

Why each option matters

Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.

Correct answer & explanation

✓

Provisioners run only when the resource is created, not on subsequent updates.

Provisioners in Terraform are designed to run only during resource creation, not during subsequent updates. When the instance type is modified and 'terraform apply' is run again, Terraform updates the existing resource in place without triggering the provisioner again. This behavior is intentional because provisioners are typically used for initial setup tasks like bootstrapping, not for ongoing configuration changes.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

✗
Provisioners run only when the resource is destroyed.
Why it's wrong here
Provisioners run on create and optionally on destroy.
✗
The provisioner should be 'remote-exec' to run on updates.
Why it's wrong here
The type does not affect update behavior.
✗
The command syntax is incorrect.
Why it's wrong here
The command syntax is correct.
✓
Provisioners run only when the resource is created, not on subsequent updates.
Why this is correct
Provisioners are not re-run on updates unless triggers specify.

Go deeper

TF-004 Use Terraform outside the core workflow Practice Question

Exhibit

Why each option matters

Option-by-option breakdown

Related to this question