Multi-Cloud Infrastructure Deployment with Terraform

What is Terraform?

Terraform by HashiCorp is an open-source Infrastructure as Code (IaC) tool that lets you define and provision infrastructure across multiple cloud providers using a single, consistent language (HCL).

Why Terraform? Write once, deploy anywhere. Same workflow (init, plan, apply) works across all cloud providers.

Official Docs: Terraform Documentation | Download & Install

Prerequisites

1. Install Terraform CLI — Download here
2. Create a free account on your cloud provider (AWS / GCP / Azure)
3. Install the respective CLI tool for authentication

Verify installation:

terraform -version

Core Terraform Workflow

These 4 commands are all you need for every cloud provider:

# 1. Initialize the working directory & download providers
terraform init

# 2. Preview the changes Terraform will make
terraform plan

# 3. Apply the configuration to create resources
terraform apply

# 4. Destroy resources when no longer needed
terraform destroy

Cloud Provider Examples

Click a provider to see setup instructions and copy-ready sample code.

aws configure
# Enter: Access Key, Secret Key, Region, Output format

terraform {
  required_providers {
    aws = {
      source  = "hashicorp/aws"
      version = "~> 5.0"
    }
  }
}

provider "aws" {
  region = "us-east-1"
}

resource "aws_instance" "web_server" {
  ami           = "ami-0c55b159cbfafe1f0"
  instance_type = "t2.micro"

  tags = {
    Name = "Terraform-Web-Server"
  }
}

resource "aws_s3_bucket" "app_bucket" {
  bucket = "my-terraform-demo-bucket-12345"
  tags   = { Environment = "Dev" }
}

output "instance_public_ip" {
  value = aws_instance.web_server.public_ip
}

terraform init && terraform plan && terraform apply

gcloud auth application-default login
gcloud config set project YOUR_PROJECT_ID

terraform {
  required_providers {
    google = {
      source  = "hashicorp/google"
      version = "~> 5.0"
    }
  }
}

provider "google" {
  project = "your-gcp-project-id"
  region  = "us-central1"
  zone    = "us-central1-a"
}

resource "google_compute_instance" "vm_instance" {
  name         = "terraform-vm"
  machine_type = "e2-micro"

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

  network_interface {
    network = "default"
    access_config {}
  }
}

resource "google_storage_bucket" "app_bucket" {
  name          = "my-terraform-demo-bucket-12345"
  location      = "US"
  force_destroy = true
}

output "vm_external_ip" {
  value = google_compute_instance.vm_instance.network_interface[0].access_config[0].nat_ip
}

terraform init && terraform plan && terraform apply

az login
az account set --subscription "YOUR_SUBSCRIPTION_ID"

terraform {
  required_providers {
    azurerm = {
      source  = "hashicorp/azurerm"
      version = "~> 3.0"
    }
  }
}

provider "azurerm" {
  features {}
}

resource "azurerm_resource_group" "rg" {
  name     = "terraform-rg"
  location = "East US"
}

resource "azurerm_storage_account" "storage" {
  name                     = "tfdemostorage12345"
  resource_group_name      = azurerm_resource_group.rg.name
  location                 = azurerm_resource_group.rg.location
  account_tier             = "Standard"
  account_replication_type = "LRS"
}

resource "azurerm_virtual_network" "vnet" {
  name                = "terraform-vnet"
  address_space       = ["10.0.0.0/16"]
  location            = azurerm_resource_group.rg.location
  resource_group_name = azurerm_resource_group.rg.name
}

output "resource_group_name" {
  value = azurerm_resource_group.rg.name
}

terraform init && terraform plan && terraform apply

Deploying to All Three Clouds at Once

Combine all providers in a single Terraform configuration:

terraform {
  required_providers {
    aws     = { source = "hashicorp/aws",     version = "~> 5.0" }
    google  = { source = "hashicorp/google",  version = "~> 5.0" }
    azurerm = { source = "hashicorp/azurerm", version = "~> 3.0" }
  }
}

provider "aws"     { region = "us-east-1" }
provider "google"  { project = "your-gcp-project-id"; region = "us-central1" }
provider "azurerm" { features {} }

# AWS S3 Bucket
resource "aws_s3_bucket" "aws_store" {
  bucket = "multicloud-aws-bucket-12345"
}

# GCP Storage Bucket
resource "google_storage_bucket" "gcp_store" {
  name     = "multicloud-gcp-bucket-12345"
  location = "US"
}

# Azure Resource Group
resource "azurerm_resource_group" "azure_rg" {
  name     = "multicloud-rg"
  location = "East US"
}

Run terraform apply once — Terraform provisions resources across all three clouds in parallel.

Quick Comparison

Video Tutorial

Best Practices

• Use remote state: Store terraform.tfstate in S3, GCS, or Azure Blob for team collaboration.
• Never commit secrets: Use environment variables or secret managers.
• Use variables & modules: Keep code DRY and reusable.
• Always run terraform plan before applying.
• Use version constraints for providers to avoid breaking changes.

Learn more: Terraform Modules | Remote State Backends