Why the workflow matters in Terraform - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to initialize the Terraform working directory.

Terraform

terraform [1]

Drag options to blanks, or click blank then click option'

Ainit

Bapply

Cplan

Ddestroy

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'apply' before initializing causes errors.

Confusing 'plan' with initialization.

The terraform init command sets up the working directory by downloading necessary plugins and preparing the environment.

2fill in blank

medium

Complete the code to see what changes Terraform will make.

Terraform

terraform [1]

Drag options to blanks, or click blank then click option'

Ainit

Bplan

Capply

Dvalidate

Attempts:

3 left

💡 Hint

Common Mistakes

Running 'apply' without checking the plan first.

Using 'init' instead of 'plan' to preview changes.

The terraform plan command shows the changes Terraform will apply without making any changes yet.

3fill in blank

hard

Fix the error in the command to apply changes safely.

Terraform

terraform [1] -auto-approve

Drag options to blanks, or click blank then click option'

Aplan

Brefresh

Capply

Ddestroy

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'plan' with '-auto-approve' which does nothing.

Confusing 'destroy' with applying changes.

The terraform apply -auto-approve command applies changes without asking for confirmation, which should be used carefully.

4fill in blank

hard

Fill both blanks to create a resource and output its ID.

Terraform

resource "aws_instance" "example" {
  ami           = "ami-123456"
  instance_type = "t2.micro"
}

output "instance_id" {
  value = aws_instance.[1].[2]
}

Drag options to blanks, or click blank then click option'

Aexample

Bid

Cname

Dinstance

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'name' instead of 'id' for the output value.

Using a wrong resource name.

The resource name is example and the attribute to get the instance ID is id.

5fill in blank

hard

Fill all three blanks to define a variable with a default value and use it in a resource.

Terraform

variable "[1]" {
  type    = string
  default = "[2]"
}

resource "aws_s3_bucket" "bucket" {
  bucket = var.[3]
  acl    = "private"
}

Drag options to blanks, or click blank then click option'

Abucket_name

Bmy-bucket-123

Dbucket_id

Attempts:

3 left

💡 Hint

Common Mistakes

Mismatching variable names between declaration and usage.

Using an incorrect default value format.

The variable is named bucket_name, its default value is my-bucket-123, and the resource uses var.bucket_name.

Practice

1. Why is it important to run terraform plan before terraform apply?

easy

A. It shows the changes Terraform will make before applying them

B. It automatically applies changes without confirmation

C. It deletes all existing resources immediately

D. It skips validation of the configuration files

Solution

1. Step 1: Understand the purpose of terraform plan

   This command previews the changes Terraform will make to your infrastructure without applying them.

2. Step 2: Compare with terraform apply

   terraform apply actually makes the changes, so planning first helps avoid mistakes.

3. Final Answer:

   It shows the changes Terraform will make before applying them -> Option A

4. Quick Check:

   Plan previews changes = D [OK]

Hint: Plan first to preview changes, avoid surprises [OK]

Common Mistakes:

• Skipping plan and applying directly
• Thinking plan applies changes
• Confusing plan with destroy

2. Which command correctly initializes a Terraform working directory before planning or applying?

easy

A. terraform init

B. terraform start

C. terraform deploy

D. terraform configure

Solution

1. Step 1: Identify the initialization command

   terraform init sets up the working directory by downloading providers and preparing backend.

2. Step 2: Check other options

   Commands like terraform start, deploy, or configure do not exist in Terraform.

3. Final Answer:

   terraform init -> Option A

4. Quick Check:

   Initialize with init = B [OK]

Hint: Init first to prepare your workspace [OK]

Common Mistakes:

• Using non-existent commands
• Trying to apply before init
• Confusing init with plan

3. Given this Terraform workflow:

terraform init
tf plan
tf apply

What will happen if you run terraform apply without running terraform plan first?

medium

A. Terraform will apply changes immediately without preview

B. Terraform will show an error and stop

C. Terraform will automatically run plan before apply

D. Terraform will delete all resources

Solution

1. Step 1: Understand terraform apply behavior

   Terraform always performs an internal plan, shows the execution plan (preview of changes), and prompts for confirmation before applying.

2. Step 2: Check if plan is mandatory

   Running terraform plan first is recommended for detailed review and saving plans, but terraform apply automatically runs the plan step.

3. Final Answer:

   Terraform will automatically run plan before apply -> Option C

4. Quick Check:

   Apply auto-runs plan [OK]

Hint: Apply always plans first internally [OK]

Common Mistakes:

• Assuming apply always errors without plan
• Thinking apply auto-runs plan silently
• Believing apply deletes resources by default

4. You ran terraform apply but noticed unexpected resource deletions. What is the most likely cause related to workflow?

medium

A. Running terraform init twice

B. Skipping terraform plan and not reviewing changes

C. Using an outdated Terraform version

D. Not setting environment variables

Solution

1. Step 1: Identify workflow mistake

   Skipping terraform plan means you miss previewing changes, leading to surprises like deletions.

2. Step 2: Evaluate other options

   Running init twice, outdated version, or missing env vars usually cause errors, not unexpected deletions.

3. Final Answer:

   Skipping terraform plan and not reviewing changes -> Option B

4. Quick Check:

   Skip plan = risk of unwanted deletions [OK]

Hint: Always plan and review before applying [OK]

Common Mistakes:

• Ignoring plan output
• Blaming init for deletions
• Assuming version causes deletions

5. You want to safely update your cloud infrastructure with Terraform. Which workflow sequence best prevents downtime and mistakes?

hard

A. terraform plan -> terraform apply -> terraform init

B. terraform apply -> terraform plan -> terraform init

C. terraform apply -> terraform init -> terraform plan

D. terraform init -> terraform plan -> review plan -> terraform apply

Solution

1. Step 1: Understand the correct workflow order

   First, terraform init prepares the workspace, then terraform plan previews changes, followed by reviewing the plan carefully.

2. Step 2: Apply changes only after review

   Applying changes after review ensures safety and avoids downtime or mistakes.

3. Final Answer:

   terraform init -> terraform plan -> review plan -> terraform apply -> Option D

4. Quick Check:

   Init, plan, review, apply = C [OK]

Hint: Init, plan, review, then apply for safe updates [OK]

Common Mistakes:

• Applying before planning
• Skipping plan review
• Running commands in wrong order