Azure仮想マシン作成をARMテンプレートで完全自動化｜Bicepで再現性を高める実践手順

この記事のポイント

・ ARMテンプレートはJSONでVMリソースを定義し、az deployment group createで繰り返しデプロイできる
・ BicepはARMテンプレートの上位言語で可読性が高く、bicep buildでJSONに変換できる
・ parametersファイルを分けると開発・本番の設定を1コマンドで切り替えられる
・ デプロイ失敗時はaz deployment group show --queryでエラー詳細を素早く確認できる

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "vmName": {
      "type": "string",
      "defaultValue": "myLinuxVM"
    },
    "adminUsername": {
      "type": "string"
    },
    "adminSshPublicKey": {
      "type": "string"
    },
    "location": {
      "type": "string",
      "defaultValue": "[resourceGroup().location]"
    }
  },
  "variables": {
    "vnetName": "[concat(parameters('vmName'), '-vnet')]",
    "subnetName": "default",
    "nicName": "[concat(parameters('vmName'), '-nic')]",
    "publicIpName": "[concat(parameters('vmName'), '-pip')]"
  },
  "resources": [
    {
      "type": "Microsoft.Network/virtualNetworks",
      "apiVersion": "2023-04-01",
      "name": "[variables('vnetName')]",
      "location": "[parameters('location')]",
      "properties": {
        "addressSpace": {
          "addressPrefixes": ["10.0.0.0/16"]
        },
        "subnets": [
          {
            "name": "[variables('subnetName')]",
            "properties": {
              "addressPrefix": "10.0.0.0/24"
            }
          }
        ]
      }
    },
    {
      "type": "Microsoft.Network/publicIPAddresses",
      "apiVersion": "2023-04-01",
      "name": "[variables('publicIpName')]",
      "location": "[parameters('location')]",
      "sku": { "name": "Standard" },
      "properties": {
        "publicIPAllocationMethod": "Static"
      }
    },
    {
      "type": "Microsoft.Network/networkInterfaces",
      "apiVersion": "2023-04-01",
      "name": "[variables('nicName')]",
      "location": "[parameters('location')]",
      "dependsOn": [
        "[resourceId('Microsoft.Network/virtualNetworks', variables('vnetName'))]",
        "[resourceId('Microsoft.Network/publicIPAddresses', variables('publicIpName'))]"
      ],
      "properties": {
        "ipConfigurations": [
          {
            "name": "ipconfig1",
            "properties": {
              "privateIPAllocationMethod": "Dynamic",
              "publicIPAddress": {
                "id": "[resourceId('Microsoft.Network/publicIPAddresses', variables('publicIpName'))]"
              },
              "subnet": {
                "id": "[resourceId('Microsoft.Network/virtualNetworks/subnets', variables('vnetName'), variables('subnetName'))]"
              }
            }
          }
        ]
      }
    },
    {
      "type": "Microsoft.Compute/virtualMachines",
      "apiVersion": "2023-07-01",
      "name": "[parameters('vmName')]",
      "location": "[parameters('location')]",
      "dependsOn": [
        "[resourceId('Microsoft.Network/networkInterfaces', variables('nicName'))]"
      ],
      "properties": {
        "hardwareProfile": {
          "vmSize": "Standard_B2s"
        },
        "osProfile": {
          "computerName": "[parameters('vmName')]",
          "adminUsername": "[parameters('adminUsername')]",
          "linuxConfiguration": {
            "disablePasswordAuthentication": true,
            "ssh": {
              "publicKeys": [
                {
                  "path": "[concat('/home/', parameters('adminUsername'), '/.ssh/authorized_keys')]",
                  "keyData": "[parameters('adminSshPublicKey')]"
                }
              ]
            }
          }
        },
        "storageProfile": {
          "imageReference": {
            "publisher": "Canonical",
            "offer": "ubuntu-24_04-lts",
            "sku": "server",
            "version": "latest"
          },
          "osDisk": {
            "createOption": "FromImage",
            "managedDisk": {
              "storageAccountType": "Premium_LRS"
            }
          }
        },
        "networkProfile": {
          "networkInterfaces": [
            {
              "id": "[resourceId('Microsoft.Network/networkInterfaces', variables('nicName'))]"
            }
          ]
        }
      }
    }
  ],
  "outputs": {
    "publicIpAddress": {
      "type": "string",
      "value": "[reference(variables('publicIpName')).ipAddress]"
    }
  }
}

# リソースグループを作成する（未作成の場合）
az group create --name myResourceGroup --location japaneast

# ARMテンプレートをデプロイする
az deployment group create \
  --resource-group myResourceGroup \
  --template-file vm-deploy.json \
  --parameters adminUsername=azureuser \
               adminSshPublicKey="$(cat ~/.ssh/id_rsa.pub)"

# 出力例（環境により異なります）
{
  "outputs": {
    "publicIpAddress": {
      "type": "String",
      "value": "20.xxx.xxx.xxx"
    }
  },
  "provisioningState": "Succeeded"
}

ssh azureuser@20.xxx.xxx.xxx

# Bicepのインストール
az bicep install

# バージョン確認
az bicep version

# 出力例（環境により異なります）
Bicep CLI version 0.30.x (xxxxxxxx)

param vmName string = 'myLinuxVM'
param adminUsername string
@secure()
param adminSshPublicKey string
param location string = resourceGroup().location

var vnetName = '${vmName}-vnet'
var subnetName = 'default'
var nicName = '${vmName}-nic'
var publicIpName = '${vmName}-pip'

resource vnet 'Microsoft.Network/virtualNetworks@2023-04-01' = {
  name: vnetName
  location: location
  properties: {
    addressSpace: {
      addressPrefixes: ['10.0.0.0/16']
    }
    subnets: [
      {
        name: subnetName
        properties: {
          addressPrefix: '10.0.0.0/24'
        }
      }
    ]
  }
}

resource publicIp 'Microsoft.Network/publicIPAddresses@2023-04-01' = {
  name: publicIpName
  location: location
  sku: {
    name: 'Standard'
  }
  properties: {
    publicIPAllocationMethod: 'Static'
  }
}

resource nic 'Microsoft.Network/networkInterfaces@2023-04-01' = {
  name: nicName
  location: location
  properties: {
    ipConfigurations: [
      {
        name: 'ipconfig1'
        properties: {
          privateIPAllocationMethod: 'Dynamic'
          publicIPAddress: {
            id: publicIp.id
          }
          subnet: {
            id: vnet.properties.subnets[0].id
          }
        }
      }
    ]
  }
}

resource vm 'Microsoft.Compute/virtualMachines@2023-07-01' = {
  name: vmName
  location: location
  properties: {
    hardwareProfile: {
      vmSize: 'Standard_B2s'
    }
    osProfile: {
      computerName: vmName
      adminUsername: adminUsername
      linuxConfiguration: {
        disablePasswordAuthentication: true
        ssh: {
          publicKeys: [
            {
              path: '/home/${adminUsername}/.ssh/authorized_keys'
              keyData: adminSshPublicKey
            }
          ]
        }
      }
    }
    storageProfile: {
      imageReference: {
        publisher: 'Canonical'
        offer: 'ubuntu-24_04-lts'
        sku: 'server'
        version: 'latest'
      }
      osDisk: {
        createOption: 'FromImage'
        managedDisk: {
          storageAccountType: 'Premium_LRS'
        }
      }
    }
    networkProfile: {
      networkInterfaces: [
        {
          id: nic.id
        }
      ]
    }
  }
}

output publicIpAddress string = publicIp.properties.ipAddress

# Bicepファイルを直接デプロイ（az bicep buildは不要）
az deployment group create \
  --resource-group myResourceGroup \
  --template-file vm-deploy.bicep \
  --parameters adminUsername=azureuser \
               adminSshPublicKey="$(cat ~/.ssh/id_rsa.pub)"

# ARMテンプレートJSONに変換したい場合（確認用）
az bicep build --file vm-deploy.bicep
# → vm-deploy.json が生成される

# params-dev.json（開発環境用）
{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentParameters.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "vmName": {
      "value": "vm-dev"
    },
    "adminUsername": {
      "value": "devadmin"
    },
    "adminSshPublicKey": {
      "value": "ssh-rsa AAAA..."
    }
  }
}

# params-prod.json（本番環境用）
{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentParameters.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "vmName": {
      "value": "vm-prod"
    },
    "adminUsername": {
      "value": "prodadmin"
    },
    "adminSshPublicKey": {
      "value": "ssh-rsa AAAA..."
    }
  }
}

# 開発環境にデプロイ
az deployment group create \
  --resource-group rg-dev \
  --template-file vm-deploy.bicep \
  --parameters @params-dev.json

# 本番環境にデプロイ
az deployment group create \
  --resource-group rg-prod \
  --template-file vm-deploy.bicep \
  --parameters @params-prod.json

# デプロイ操作の一覧を取得する
az deployment group list \
  --resource-group myResourceGroup \
  --query "[].{name:name, state:properties.provisioningState}" \
  --output table

# エラー詳細を確認する（デプロイ名は上の出力から取得）
az deployment group show \
  --resource-group myResourceGroup \
  --name <デプロイ名> \
  --query "properties.error"

# 出力例（環境により異なります）
{
  "code": "InvalidTemplateDeployment",
  "message": "The template deployment ... failed ...",
  "details": [
    {
      "code": "QuotaExceeded",
      "message": "Operation results in exceeding quota limits..."
    }
  ]
}

# ARMテンプレートの場合: dependsOnを明示的に設定する
"dependsOn": [
  "[resourceId('Microsoft.Network/virtualNetworks', variables('vnetName'))]"
]

# Bicepの場合: リソースの参照を使えば依存関係は自動解決される
# subnet の id を vnet.properties.subnets[0].id のように参照する

# デプロイ前のバリデーション
az deployment group validate \
  --resource-group myResourceGroup \
  --template-file vm-deploy.bicep \
  --parameters @params-dev.json

# What-If確認（実際に何が変更されるか事前確認）
az deployment group what-if \
  --resource-group myResourceGroup \
  --template-file vm-deploy.bicep \
  --parameters @params-dev.json