Provision a GCP VM with Terraform

Prerequisites

Before we start, make sure you have:

A GCP project with billing enabled.
Service Account with Compute Admin & Storage Admin roles.
Terraform installed (terraform -v).
Service Account key file (.json) downloaded.

Step-by-Step: Provision a VM on GCP using Terraform

📁 1. Create a Project Directory

mkdir terraform-gcp-vm
cd terraform-gcp-vm

📄 2. Create `main.tf`

provider "google" {
  credentials = file("path-to-your-service-account-key.json")
  project     = "your-gcp-project-id"
  region      = "us-central1"
  zone        = "us-central1-a"
}

resource "google_compute_instance" "vm_instance" {
  name         = "demo-vm"
  machine_type = "e2-micro"
  zone         = "us-central1-a"

  boot_disk {
    initialize_params {
      image = "debian-cloud/debian-11"
    }
  }

  network_interface {
    network = "default"

    access_config {
      # Ephemeral public IP
    }
  }

  metadata_startup_script = <<-EOT
    #! /bin/bash
    sudo apt update
    sudo apt install -y apache2
    sudo systemctl start apache2
    echo "Hello from Terraform GCP VM!" > /var/www/html/index.html
  EOT
}

This script:

Creates a e2-micro VM in the default network
Installs Apache
Displays a welcome message

3. (Optional) Add Variables in `variables.tf`

variable "project_id" {}
variable "region" {
  default = "us-central1"
}
variable "zone" {
  default = "us-central1-a"
}

Then reference them in main.tf using var.project_id, var.region, etc.

4. Initialize Terraform

terraform init

This downloads the Google Cloud provider plugin.

5. Preview the Changes

terraform plan

You'll see what Terraform will create — always review before applying.

6. Apply the Configuration

terraform apply

Type yes when prompted.

7. Verify on GCP Console

Go to Compute Engine → VM Instances — you should see demo-vm running.

Visit the External IP in your browser → you'll see the Apache welcome message.

8. Destroy the Resources

When you're done, destroy everything:

terraform destroy

For Best Practices

Use remote backends (like GCS) to store .tfstate safely.
Separate configuration into modules (network, compute, etc.).
Manage secrets using terraform.tfvars and .gitignore them.
Tag and label all resources for cost tracking and clarity.
Use terraform fmt to format your code.