Managing GCP Compute Engine with Terraform

In this guide, we’ll explore how to manage Google Cloud Platform (GCP) Compute Engine using Terraform.

Video Tutorial

Prerequisites

• Google Cloud SDK installed and configured
• Terraform installed (version 1.0.0 or later)
• Basic understanding of GCP concepts
• A GCP project with billing enabled

Project Structure

.
├── main.tf                   # Main Terraform configuration file
├── variables.tf              # Variable definitions
├── outputs.tf               # Output definitions
├── terraform.tfvars         # Variable values
└── modules/
    └── compute/
        ├── main.tf          # Compute Engine specific configurations
        ├── variables.tf      # Module variables
        ├── instances.tf     # Instance configurations
        └── outputs.tf       # Module outputs

Provider Configuration

terraform {
  required_providers {
    google = {
      source  = "hashicorp/google"
      version = "~> 4.0"
    }
  }
}

provider "google" {
  project = var.project_id
  region  = var.region
  zone    = var.zone
}

Variables

variable "project_id" {
  description = "The ID of the GCP project"
  type        = string
}

variable "region" {
  description = "The region to deploy resources to"
  type        = string
  default     = "us-central1"
}

variable "zone" {
  description = "The zone to deploy resources to"
  type        = string
  default     = "us-central1-a"
}

variable "instance_name" {
  description = "Name for the compute instance"
  type        = string
}

variable "machine_type" {
  description = "The machine type to use"
  type        = string
  default     = "e2-medium"
}

Network Configuration

resource "google_compute_network" "vpc_network" {
  name                    = "terraform-network"
  auto_create_subnetworks = false
}

resource "google_compute_subnetwork" "subnet" {
  name          = "terraform-subnet"
  ip_cidr_range = "10.0.1.0/24"
  network       = google_compute_network.vpc_network.id
  region        = var.region
}

resource "google_compute_firewall" "allow_ssh" {
  name    = "allow-ssh"
  network = google_compute_network.vpc_network.name

  allow {
    protocol = "tcp"
    ports    = ["22"]
  }

  source_ranges = ["0.0.0.0/0"]
}

Compute Instance

resource "google_compute_instance" "vm_instance" {
  name         = var.instance_name
  machine_type = var.machine_type
  zone         = var.zone

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

  network_interface {
    subnetwork = google_compute_subnetwork.subnet.id
    access_config {
      // Ephemeral public IP
    }
  }

  metadata = {
    ssh-keys = "debian:${file("~/.ssh/id_rsa.pub")}"
  }

  tags = ["ssh-allowed"]
}

Outputs

output "instance_ip" {
  description = "The public IP of the compute instance"
  value       = google_compute_instance.vm_instance.network_interface[0].access_config[0].nat_ip
}

output "instance_name" {
  description = "The name of the compute instance"
  value       = google_compute_instance.vm_instance.name
}

Best Practices

1. Security:

   • Use custom service accounts
   • Implement least privilege access
   • Use secure boot options

2. Networking:

   • Use private Google Access
   • Implement proper firewall rules
   • Use VPC Service Controls

3. Cost Optimization:

   • Use preemptible instances when possible
   • Right-size instances
   • Use committed use discounts

4. Maintenance:

   • Enable automatic updates
   • Use startup scripts
   • Implement proper backup strategies

Common Operations

Creating Resources

terraform init
terraform plan
terraform apply

Destroying Resources

terraform destroy

Updating Instance

# Modify the configuration
terraform plan
terraform apply

Best Practices and Tips

1. Resource Management:

   • Use labels for better organization
   • Implement proper backup strategies
   • Monitor resource usage

2. Security:

   • Implement proper IAM roles
   • Use secure communications
   • Regular security audits

3. Performance:

   • Choose appropriate machine types
   • Monitor performance metrics
   • Use SSD persistent disks

Conclusion

You’ve learned how to set up and manage GCP Compute Engine using Terraform. This setup provides:

• Automated infrastructure deployment
• Consistent environment configuration
• Easy scaling and management
• Secure and efficient compute resources