terraform azure to create 3 linux machines

commands.sh

# make sure terraform CLI is installed
terraform

# format the tf files
terraform fmt

# initialize terraform Azure modules
terraform init

# validate the template
terraform validate

# plan and save the infra changes into tfplan file
terraform plan -out tfplan

# show the tfplan file
terraform show -json tfplan
terraform show -json tfplan >> tfplan.json

# Format tfplan.json file
terraform show -json tfplan | jq '.' > tfplan.json

# apply the infra changes
terraform apply tfplan

# delete the infra
terraform destroy

# cleanup files
rm terraform.tfstate
rm terraform.tfstate.backup
rm tfplan
rm tfplan.json
rm -r .terraform/

providers.tf

provider "azurerm" {
  features {}
}

terraform {
  required_providers {
    azurerm = {
      source  = "hashicorp/azurerm"
      version = "2.78.0"
    }
  }
}

main.tf

# Create a resource group if it doesn't exist
resource "azurerm_resource_group" "rg" {
  name     = var.resource_group_name
  location = var.resource_group_location

  tags = {
    environment = "production"
  }
}

# Create virtual network
resource "azurerm_virtual_network" "vnet" {
  name                = var.virtual_network_name
  address_space       = ["10.0.0.0/16"]
  location            = azurerm_resource_group.rg.location
  resource_group_name = azurerm_resource_group.rg.name

  tags = {
    environment = "production"
  }
}

# Create subnet
resource "azurerm_subnet" "subnet" {
  name                 = var.subnet_name
  resource_group_name  = azurerm_resource_group.rg.name
  virtual_network_name = azurerm_virtual_network.vnet.name
  address_prefixes     = ["10.0.1.0/24"]
}

# Create public IPs
resource "azurerm_public_ip" "public_ip" {
  name                = var.public_ip_name
  location            = azurerm_resource_group.rg.location
  resource_group_name = azurerm_resource_group.rg.name
  allocation_method   = "Dynamic"

  tags = {
    environment = "production"
  }
}

resource "azurerm_public_ip" "public_ip2" {
  name                = var.public_ip_name2
  location            = azurerm_resource_group.rg.location
  resource_group_name = azurerm_resource_group.rg.name
  allocation_method   = "Dynamic"

  tags = {
    environment = "production"
  }
}

resource "azurerm_public_ip" "public_ip3" {
  name                = var.public_ip_name3
  location            = azurerm_resource_group.rg.location
  resource_group_name = azurerm_resource_group.rg.name
  allocation_method   = "Dynamic"

  tags = {
    environment = "production"
  }
}

# Create Network Security Group and rule
resource "azurerm_network_security_group" "nsg" {
  name                = var.network_security_group_name
  location            = azurerm_resource_group.rg.location
  resource_group_name = azurerm_resource_group.rg.name

  security_rule {
    name                       = "SSH"
    priority                   = 1001
    direction                  = "Inbound"
    access                     = "Allow"
    protocol                   = "Tcp"
    source_port_range          = "*"
    destination_port_ranges     = ["22", "8080"]
    source_address_prefix      = "*"
    destination_address_prefix = "*"
  }

  tags = {
    environment = "production"
  }
}

# Create network interface
resource "azurerm_network_interface" "nic" {
  name                = var.network_interface_name
  location            = azurerm_resource_group.rg.location
  resource_group_name = azurerm_resource_group.rg.name

  ip_configuration {
    name                          = "myNicConfiguration"
    subnet_id                     = azurerm_subnet.subnet.id
    private_ip_address_allocation = "Dynamic"
    public_ip_address_id          = azurerm_public_ip.public_ip.id
  }

  tags = {
    environment = "production"
  }
}

resource "azurerm_network_interface" "nic2" {
  name                = var.network_interface_name2
  location            = azurerm_resource_group.rg.location
  resource_group_name = azurerm_resource_group.rg.name

  ip_configuration {
    name                          = "myNicConfiguration2"
    subnet_id                     = azurerm_subnet.subnet.id
    private_ip_address_allocation = "Dynamic"
    public_ip_address_id          = azurerm_public_ip.public_ip2.id
  }

  tags = {
    environment = "production"
  }
}

resource "azurerm_network_interface" "nic3" {
  name                = var.network_interface_name3
  location            = azurerm_resource_group.rg.location
  resource_group_name = azurerm_resource_group.rg.name

  ip_configuration {
    name                          = "myNicConfiguration3"
    subnet_id                     = azurerm_subnet.subnet.id
    private_ip_address_allocation = "Dynamic"
    public_ip_address_id          = azurerm_public_ip.public_ip3.id
  }

  tags = {
    environment = "production"
  }
}

# Connect the security group to the network interface
resource "azurerm_network_interface_security_group_association" "association" {
  network_interface_id      = azurerm_network_interface.nic.id
  network_security_group_id = azurerm_network_security_group.nsg.id
}

resource "azurerm_network_interface_security_group_association" "association2" {
  network_interface_id      = azurerm_network_interface.nic2.id
  network_security_group_id = azurerm_network_security_group.nsg.id
}

resource "azurerm_network_interface_security_group_association" "association3" {
  network_interface_id      = azurerm_network_interface.nic3.id
  network_security_group_id = azurerm_network_security_group.nsg.id
}

# Generate random text for a unique storage account name
resource "random_id" "randomId" {
  keepers = {
    # Generate a new ID only when a new resource group is defined
    resource_group = azurerm_resource_group.rg.name
  }

  byte_length = 8
}

# Create storage account for boot diagnostics
resource "azurerm_storage_account" "storage" {
  name                     = "diag${random_id.randomId.hex}"
  resource_group_name      = azurerm_resource_group.rg.name
  location                 = azurerm_resource_group.rg.location
  account_tier             = "Standard"
  account_replication_type = "LRS"

  tags = {
    environment = "production"
  }
}

# Create (and display) an SSH key
resource "tls_private_key" "example_ssh" {
  algorithm = "RSA"
  rsa_bits  = 4096
}

# Create virtual machine
resource "azurerm_linux_virtual_machine" "linuxvm" {
  name                  = var.linux_virtual_machine_name
  location              = azurerm_resource_group.rg.location
  resource_group_name   = azurerm_resource_group.rg.name
  network_interface_ids = [azurerm_network_interface.nic.id]
  size                  = "Standard_DS1_v2"

  os_disk {
    name                 = "myOsDisk"
    caching              = "ReadWrite"
    storage_account_type = "Premium_LRS"
  }

  source_image_reference {
    publisher = "OpenLogic"
    offer     = "CentOS"
    sku       = "8_4"
    version   = "latest"
  }

  computer_name                   = var.linux_virtual_machine_name
  admin_username                  = "azureuser"
  disable_password_authentication = true

  admin_ssh_key {
    username   = "azureuser"
    public_key = tls_private_key.example_ssh.public_key_openssh
  }

  boot_diagnostics {
    storage_account_uri = azurerm_storage_account.storage.primary_blob_endpoint
  }

  tags = {
    environment = "production"
  }
}

resource "azurerm_linux_virtual_machine" "linuxvm2" {
  name                  = var.linux_virtual_machine_name2
  location              = azurerm_resource_group.rg.location
  resource_group_name   = azurerm_resource_group.rg.name
  network_interface_ids = [azurerm_network_interface.nic2.id]
  size                  = "Standard_DS1_v2"

  os_disk {
    name                 = "myOsDisk2"
    caching              = "ReadWrite"
    storage_account_type = "Premium_LRS"
  }

  source_image_reference {
    publisher = "OpenLogic"
    offer     = "CentOS"
    sku       = "8_4"
    version   = "latest"
  }

  computer_name                   = var.linux_virtual_machine_name2
  admin_username                  = "azureuser"
  disable_password_authentication = true

  admin_ssh_key {
    username   = "azureuser"
    public_key = tls_private_key.example_ssh.public_key_openssh
  }

  boot_diagnostics {
    storage_account_uri = azurerm_storage_account.storage.primary_blob_endpoint
  }

  tags = {
    environment = "production"
  }
}

resource "azurerm_linux_virtual_machine" "linuxvm3" {
  name                  = var.linux_virtual_machine_name3
  location              = azurerm_resource_group.rg.location
  resource_group_name   = azurerm_resource_group.rg.name
  network_interface_ids = [azurerm_network_interface.nic3.id]
  size                  = "Standard_DS1_v2"

  os_disk {
    name                 = "myOsDisk3"
    caching              = "ReadWrite"
    storage_account_type = "Premium_LRS"
  }

  source_image_reference {
    publisher = "OpenLogic"
    offer     = "CentOS"
    sku       = "8_4"
    version   = "latest"
  }

  computer_name                   = var.linux_virtual_machine_name3
  admin_username                  = "azureuser"
  disable_password_authentication = true

  admin_ssh_key {
    username   = "azureuser"
    public_key = tls_private_key.example_ssh.public_key_openssh
  }

  boot_diagnostics {
    storage_account_uri = azurerm_storage_account.storage.primary_blob_endpoint
  }

  tags = {
    environment = "production"
  }
}

variables.tf

variable "resource_group_name" {
  type        = string
  description = "RG name in Azure"
}

variable "resource_group_location" {
  type        = string
  description = "RG location in Azure"
}

variable "virtual_network_name" {
  type        = string
  description = "VNET name in Azure"
}

variable "subnet_name" {
  type        = string
  description = "Subnet name in Azure"
}

variable "public_ip_name" {
  type        = string
  description = "Public IP name in Azure"
}
variable "public_ip_name2" {
  type        = string
  description = "Public IP name in Azure"
}

variable "public_ip_name3" {
  type        = string
  description = "Public IP name in Azure"
}

variable "network_security_group_name" {
  type        = string
  description = "NSG name in Azure"
}

variable "network_interface_name" {
  type        = string
  description = "NIC name in Azure"
}

variable "network_interface_name2" {
  type        = string
  description = "NIC name in Azure"
}

variable "network_interface_name3" {
  type        = string
  description = "NIC name in Azure"
}

variable "linux_virtual_machine_name" {
  type        = string
  description = "Linux VM name in Azure"
}

variable "linux_virtual_machine_name2" {
  type        = string
  description = "Linux VM name in Azure"
}

variable "linux_virtual_machine_name3" {
  type        = string
  description = "Linux VM name in Azure"
}

terraform.tfvars

resource_group_name         = "automation_mart"
resource_group_location     = "East US 2"
virtual_network_name        = "vnetforAutomation"
subnet_name                 = "subnetforAutomation"
public_ip_name              = "publicip019"
public_ip_name2             = "publicip020"
public_ip_name3             = "publicip021"
network_security_group_name = "nsgprod019"
network_interface_name      = "nicprod019"
network_interface_name2     = "nicprod020"
network_interface_name3     = "nicprod021"
linux_virtual_machine_name  = "jenkins"
linux_virtual_machine_name2 = "ansible"
linux_virtual_machine_name3 = "docker"

outputs.tf

output "vm_id" {
  value = azurerm_linux_virtual_machine.linuxvm.id
}

output "vm_ip" {
  value = azurerm_linux_virtual_machine.linuxvm.public_ip_address
}

output "vm_id2" {
  value = azurerm_linux_virtual_machine.linuxvm2.id
}

output "vm_ip2" {
  value = azurerm_linux_virtual_machine.linuxvm2.public_ip_address
}

output "vm_id3" {
  value = azurerm_linux_virtual_machine.linuxvm3.id
}

output "vm_ip3" {
  value = azurerm_linux_virtual_machine.linuxvm3.public_ip_address
}

output "tls_private_key" {
  value     = tls_private_key.example_ssh.private_key_pem
  sensitive = true
}

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