Terraform

Terraform 是 HashiCorp 的 Infrastructure as code 軟體，使用簡易範本化語言或 Json，提供簡單的方法來定義、預覽及部署雲端基礎結構。

• Terraform 格式以 .tf 當附檔名
• JSON 格式以 .tf.json 當附檔名

安裝

下載
下載之後只是一個 Terraform 檔案，把他複製到 /usr/local/bin 底下，就可以直接使用

terraform

官方範例

Terraform 格式，官方語法

vim aws.tf
---
# An AMI
variable "ami" {
  description = "the AMI to use"
}

/* A multi
   line comment. */
resource "aws_instance" "web" {
  ami               = "${var.ami}"
  count             = 2
  source_dest_check = false

  connection {
    user = "root"
  }
}

Json 格式

vim aws.tf.json
---
{
  "variable": {
    "ami": {
      "description": "the AMI to use"
    }
  },

  "resource": {
    "aws_instance": {
      "web": {
        "ami": "${var.ami}",
        "count": 2,
        "source_dest_check": false,

        "connection": {
          "user": "root"
        }
      }
    }
  }
}

Terraform for GCP

provider "google" {
  credentials = "${file("account.json")}"
  project     = "my-project-id"
  region      = "us-central1"
}

創建一個 GCP VM

resource "google_compute_instance" "vm_instance" {
  name         = "terraform-instance"
  machine_type = "f1-micro"

  boot_disk {
    initialize_params {
      image = "debian-cloud/debian-9"
    }
  }

  network_interface {
    # A default network is created for all GCP projects
    network       = "default"
    access_config = {
    }
  }
}

申請 GCP Service Account

下載 GCP Server 金鑰，之後重新命名為 account.json

Google 提供的映像檔

vim terrafform.tf
---
provider "google" {
  credentials = "${file("account.json")}"
  project = "{{YOUR GCP PROJECT}}"
  region  = "us-central1"
  zone    = "us-central1-c"
}

resource "google_compute_instance" "vm_instance" {
  name         = "terraform-instance"
  machine_type = "f1-micro"

  boot_disk {
    initialize_params {
      image = "centos-cloud/centos-7"
    }
  }

  network_interface {
    # A default network is created for all GCP projects
    network       = "default"
    access_config = {
    }
  }
}

初始化 Terraform

terraform init

執行 Terraform

terraform apply

輸入：yes

驗證

加入 SSH key

resource "google_compute_instance" "default" {
...
  metadata {
   sshKeys = "pellok:${file("~/.ssh/id_rsa.pub")}"
  }
}

terraform apply

清除

terraform destroy

結論

使用 Terraform 來操控 GCP，這樣就可以讓我們的雲端架構也可以程式化，讓架構可以自動化、標準化，減少人為的操控，讓主機的管理也有跡可循．在實作的過程中發現很多東西可以玩，之後可能會多加使用 Terraform 來管理主機．

參考

Terraform，自动化配置与编排必备利器
Getting started with Terraform on Google Cloud Platform