Plan and apply separation in pipelines in Terraform - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to define a Terraform backend configuration for remote state storage.

Terraform

terraform {
  backend "s3" {
    bucket = "[1]"
  }
}

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

Alocal-state

Bmy-terraform-state-bucket

Cterraform-backend

Dstate-storage

Attempts:

3 left

💡 Hint

Common Mistakes

Using a local folder name instead of an S3 bucket name.

Using a generic or incorrect bucket name.

The bucket specifies the S3 bucket name where Terraform stores the remote state. It must be the actual bucket name used for state storage.

2fill in blank

medium

Complete the code to specify the Terraform workspace for environment separation.

Terraform

terraform {
  required_version = ">= 1.0"
}

terraform workspace select [1]

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

Adev

Bdefault

Cmain

Dproduction

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'default' workspace which is shared and not environment-specific.

Using workspace names that don't match your environment naming.

Workspaces help separate environments. Here, selecting dev workspace isolates development state.

3fill in blank

hard

Fix the error in the pipeline script to apply Terraform only after planning.

Terraform

steps:
  - name: Terraform Plan
    run: terraform plan -out=plan.tfplan
  - name: Terraform Apply
    run: terraform apply [1]

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

Aplan

B-auto-approve

Cplan.tfplan

D-plan=plan.tfplan

Attempts:

3 left

💡 Hint

Common Mistakes

Using flags like '-auto-approve' without specifying the plan file.

Using incorrect flags like '-plan=plan.tfplan'.

The apply command requires the plan file name to apply the exact planned changes. The correct syntax is terraform apply plan.tfplan.

4fill in blank

hard

Fill both blanks to configure separate backend buckets and workspaces for dev and prod environments.

Terraform

terraform {
  backend "s3" {
    bucket = "[1]"
  }
}

terraform workspace select [2]

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

Aprod-terraform-state

Bdev-terraform-state

Cproduction

Ddevelopment

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing production bucket with development workspace.

Using generic or mismatched names.

Use dev-terraform-state bucket and development workspace to separate dev environment state.

5fill in blank

hard

Fill all three blanks to define a pipeline step that initializes Terraform, selects the correct workspace, and applies the plan.

Terraform

steps:
  - name: Terraform Init
    run: terraform init -backend-config=bucket=[1]
  - name: Select Workspace
    run: terraform workspace select [2]
  - name: Terraform Apply
    run: terraform apply [3]

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

Aprod-terraform-state

Bproduction

Cplan.tfplan

Ddev-terraform-state

Attempts:

3 left

💡 Hint

Common Mistakes

Using dev bucket with production workspace.

Forgetting to specify the plan file in apply.

The init step uses the production bucket, the workspace is set to production, and the apply uses the plan file.

Practice

1. What is the main benefit of separating terraform plan and terraform apply in pipelines?

easy

A. It speeds up the deployment by combining steps

B. It skips the need for state files

C. It automatically fixes errors during apply

D. It allows you to review changes before applying them

Solution

1. Step 1: Understand the purpose of terraform plan

   This command shows what changes Terraform will make without applying them.

2. Step 2: Understand the purpose of terraform apply

   This command applies the changes to the infrastructure based on the plan.

3. Final Answer:

   It allows you to review changes before applying them -> Option D

4. Quick Check:

   Plan shows changes first = B [OK]

Hint: Plan shows changes, apply makes them live [OK]

Common Mistakes:

• Thinking plan applies changes
• Believing apply skips state files
• Assuming steps run faster combined

2. Which command correctly saves a Terraform plan to a file named myplan.tfplan?

easy

A. terraform apply -out=myplan.tfplan

B. terraform save myplan.tfplan

C. terraform plan -out=myplan.tfplan

D. terraform plan save myplan.tfplan

Solution

1. Step 1: Identify the correct syntax for saving a plan

   The correct command uses terraform plan -out=filename to save the plan.

2. Step 2: Check each option

   terraform plan -out=myplan.tfplan matches the correct syntax exactly.

3. Final Answer:

   terraform plan -out=myplan.tfplan -> Option C

4. Quick Check:

   Plan with -out saves file = C [OK]

Hint: Use 'plan -out=' to save plans, not apply [OK]

Common Mistakes:

• Using apply instead of plan to save
• Using incorrect command like 'save'
• Missing the '-out=' flag

3. Given these commands run in order:
terraform plan -out=planfile
terraform apply planfile
What happens when you run terraform apply planfile?

medium

A. Terraform applies exactly the changes saved in planfile

B. Terraform ignores planfile and creates a new plan

C. Terraform applies changes but may differ from planfile

D. Terraform throws an error because planfile is not a valid command

Solution

1. Step 1: Understand the role of the saved plan file

   The plan file contains the exact changes Terraform will apply.

2. Step 2: Understand how terraform apply planfile works

   This command applies the saved plan exactly, without recalculating changes.

3. Final Answer:

   Terraform applies exactly the changes saved in planfile -> Option A

4. Quick Check:

   Apply saved plan = exact changes [OK]

Hint: Apply with plan file applies exact saved changes [OK]

Common Mistakes:

• Thinking apply recalculates plan
• Assuming apply ignores plan file
• Believing apply with plan file causes errors

4. You run terraform apply myplan.tfplan but get an error saying the plan file is invalid. What is the most likely cause?

medium

A. You forgot to run terraform init before apply

B. The plan file was created with a different Terraform version

C. You used terraform plan without -out flag

D. The plan file is empty because no changes were detected

Solution

1. Step 1: Identify compatibility issues with plan files

   Plan files are version-specific and may be invalid if Terraform versions differ.

2. Step 2: Check other options

   Running init is required but usually causes different errors; missing -out means no plan file saved; empty plan files do not cause invalid file errors.

3. Final Answer:

   The plan file was created with a different Terraform version -> Option B

4. Quick Check:

   Version mismatch causes invalid plan file error [OK]

Hint: Check Terraform versions match when using saved plans [OK]

Common Mistakes:

• Assuming missing init causes invalid plan file error
• Thinking empty plan files cause invalid file errors
• Confusing missing -out with invalid plan file

5. You want to implement a pipeline that separates planning and applying Terraform changes. Which sequence of commands ensures you can review the plan before applying exactly those changes?

hard

A. terraform plan -out=planfile && terraform apply planfile

B. terraform apply && terraform plan -out=planfile

C. terraform plan && terraform apply

D. terraform apply -out=planfile && terraform apply planfile

Solution

1. Step 1: Identify correct order for plan and apply separation

   First, run terraform plan -out=planfile to save the plan and review it.

2. Step 2: Apply the saved plan exactly

   Then, run terraform apply planfile to apply the reviewed changes exactly.

3. Final Answer:

   terraform plan -out=planfile && terraform apply planfile -> Option A

4. Quick Check:

   Plan with -out then apply saved plan = A [OK]

Hint: Plan with -out then apply saved plan file [OK]

Common Mistakes:

• Applying before planning
• Not saving plan with -out
• Using apply -out which is invalid