Terraform动态创建资源：复用配置创建Linux与Windows虚拟机

由于Terraform无法动态指定资源类型（比如根据变量切换azurerm_linux_virtual_machine和azurerm_windows_virtual_machine），我们可以通过参数复用+条件创建的方式实现需求，以下是两种可行方案：

方案一：灵活多实例配置（推荐） #

通过定义包含VM类型的实例列表变量，用for_each过滤类型，分别创建Linux和Windows虚拟机，最大化复用公共配置。

1. 定义实例列表变量 #

在variables.tf中添加：

variable "vm_instances" {
  type = list(object({
    name        = string
    type        = string # 取值为"linux"或"windows"
    size        = string
    admin_user  = string
    admin_pass  = string
    nic_id      = string
  }))
  description = "需要创建的虚拟机实例列表，包含类型、配置信息"
}

2. 复用配置创建Linux虚拟机 #

修改原有Linux资源块，通过for_each遍历过滤出Linux类型的实例：

resource "azurerm_linux_virtual_machine" "this" {
  for_each = { for vm in var.vm_instances : vm.name => vm if vm.type == "linux" }

  name                            = each.value.name
  location                        = azurerm_resource_group.rg.location
  resource_group_name             = azurerm_resource_group.rg.name
  network_interface_ids           = [each.value.nic_id]
  size                            = each.value.size
  admin_username                  = each.value.admin_user
  admin_password                  = each.value.admin_pass
  disable_password_authentication = false

  # 保留你原有Linux虚拟机的其他配置...
}

3. 同步创建Windows虚拟机 #

新增Windows资源块，复用相同的公共参数，仅保留Windows特有的配置：

resource "azurerm_windows_virtual_machine" "this" {
  for_each = { for vm in var.vm_instances : vm.name => vm if vm.type == "windows" }

  name                            = each.value.name
  location                        = azurerm_resource_group.rg.location
  resource_group_name             = azurerm_resource_group.rg.name
  network_interface_ids           = [each.value.nic_id]
  size                            = each.value.size
  admin_username                  = each.value.admin_user
  admin_password                  = each.value.admin_pass

  # Windows特有的配置（示例）
  enable_automatic_upgrades = true
  provision_vm_agent        = true
}

4. 配置实例参数 #

在terraform.tfvars中添加要创建的VM实例：

vm_instances = [
  {
    name        = "linux-vm-01"
    type        = "linux"
    size        = "Standard_D2s_v3"
    admin_user  = "linux-admin"
    admin_pass  = "L!nuxP@ss123"
    nic_id      = azurerm_network_interface.linux_nic.id
  },
  {
    name        = "windows-vm-01"
    type        = "windows"
    size        = "Standard_D2s_v3"
    admin_user  = "win-admin"
    admin_pass  = "W!nP@ss123"
    nic_id      = azurerm_network_interface.windows_nic.id
  }
]

方案二：单实例开关配置 #

如果只需要创建各一台Linux/Windows虚拟机，可以通过布尔变量控制是否创建，复用公共变量：

1. 定义开关变量 #

variable "create_linux_vm" {
  type    = bool
  default = true
}

variable "create_windows_vm" {
  type    = bool
  default = true
}

# 公共配置变量
variable "vm_size" {
  type    = string
  default = "Standard_D2s_v3"
}

variable "admin_user" {
  type    = string
  default = "admin-user"
}

variable "admin_pass" {
  type    = string
  default = "P@$$w0rd123"
}

2. 条件创建Linux虚拟机 #

resource "azurerm_linux_virtual_machine" "this" {
  count = var.create_linux_vm ? 1 : 0

  name                            = "linux-vm"
  location                        = azurerm_resource_group.rg.location
  resource_group_name             = azurerm_resource_group.rg.name
  network_interface_ids           = [azurerm_network_interface.linux_nic.id]
  size                            = var.vm_size
  admin_username                  = var.admin_user
  admin_password                  = var.admin_pass
  disable_password_authentication = false

  # 原有Linux配置...
}

3. 条件创建Windows虚拟机 #

resource "azurerm_windows_virtual_machine" "this" {
  count = var.create_windows_vm ? 1 : 0

  name                            = "windows-vm"
  location                        = azurerm_resource_group.rg.location
  resource_group_name             = azurerm_resource_group.rg.name
  network_interface_ids           = [azurerm_network_interface.windows_nic.id]
  size                            = var.vm_size
  admin_username                  = var.admin_user
  admin_password                  = var.admin_pass

  # Windows特有配置...
}

内容的提问来源于stack exchange，提问作者Fr0zt