Terraform Tutorial — terraform apply

terraform apply executes the plan and creates, updates, or destroys real infrastructure resources.

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Running apply

$ terraform apply

Terraform will perform the following actions:

  # aws_s3_bucket.main will be created
  + resource "aws_s3_bucket" "main" {
      + bucket = "my-app-bucket"
    }

Plan: 1 to add, 0 to change, 0 to destroy.

Do you want to perform these actions?
  Terraform will perform the actions described above.
  Only 'yes' will be accepted to approve.

  Enter a value: yes

aws_s3_bucket.main: Creating...
aws_s3_bucket.main: Creation complete after 3s [id=my-app-bucket]

Apply complete! Resources: 1 added, 0 changed, 0 destroyed.

Outputs:

bucket_name = "my-app-bucket"

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Apply with Auto-Approve

Skip the interactive confirmation:

$ terraform apply -auto-approve

⚠️ Warning: Only use -auto-approve in automated pipelines where a plan has already been reviewed. Never use it manually in production.

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Apply a Saved Plan

# Earlier: saved the plan
$ terraform plan -out=tfplan

# Now: apply exactly that plan
$ terraform apply tfplan

When applying a saved plan, Terraform does not prompt for confirmation because the plan was already reviewed.

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Apply with Variables

# From file
$ terraform apply -var-file="prod.tfvars"

# From command line
$ terraform apply -var="environment=prod" -var="instance_count=5"

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Apply Targeting

Apply only a specific resource:

$ terraform apply -target=aws_instance.web

Useful when:

• Debugging a single resource
• Applying a critical fix without touching everything else

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What Happens During Apply

terraform apply
  ├─ 1. Acquire state lock
  ├─ 2. Refresh state (query cloud APIs)
  ├─ 3. Generate plan
  ├─ 4. Prompt for approval
  ├─ 5. Execute changes (API calls)
  ├─ 6. Update state file
  └─ 7. Release state lock

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Handling Apply Failures

If apply fails midway (e.g., network error), Terraform:

• Saves the state with resources created so far
• Does not roll back successful resources
• Running terraform apply again continues where it left off

aws_vpc.main: Creating... ✅
aws_subnet.public: Creating... ✅
aws_instance.web: Creating... ❌ Error

# Run apply again — VPC and subnet already exist, only instance is created
$ terraform apply

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What’s Next?

You can create infrastructure. Let’s learn how to tear it all down with terraform destroy.

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← terraform plan terraform destroy →