JSON template to create a DevTest lab from a custom image

dtl-create-vm-from-customimage.json

{
  "$schema": "https://schema.management.azure.com/schemas/2015-01-01/deploymentTemplate.json",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "newVMName": {
      "type": "string",
      "metadata": {
        "description": "Name of an VM to be created"
        }
    },
    "labName": {
      "type": "string",
      "metadata": {
        "description": "Name of the DevTest lab to create the VM in"
        }
    },
    "size": {
      "type": "string",
      "metadata": {
        "description": "Size of the VM. Make sure the lab allows this size."
        }
    },
    "customImageName": {
      "type": "string",
      "metadata": {
        "description": "Name of the lab's custom image"
        }
    },
    "virtualNetworkName": {
      "type": "string",
      "metadata": {
        "description": "Name of the VNET for the VM"
        }
    },
    "subNetName": {
      "type": "string",
      "metadata": {
        "description": "Name of the subnet to put the VM in"
        }
    },
    "userName": {
      "type": "string",
      "metadata": {
        "description": "User name for the VM"
        }
    },
    "password": {
      "type": "securestring",
      "metadata": {
        "description": "Password for the VM"
        }
    }
  },
  "variables": {
    "labSubnetName": "[parameters('subNetName')]",
    "labVirtualNetworkId": "[resourceId('Microsoft.DevTestLab/labs/virtualnetworks', parameters('labName'), variables('labVirtualNetworkName'))]",
    "labVirtualNetworkName": "[parameters('virtualNetworkName')]",
    "vmId": "[resourceId ('Microsoft.DevTestLab/labs/virtualmachines', parameters('labName'), parameters('newVMName'))]",
    "vmName": "[concat(parameters('labName'), '/', parameters('newVMName'))]",
    "labnameUri": "[resourceId('microsoft.devtestlab/labs',parameters('labName'))]",
    "imageName":"[concat(variables('labnameUri'), '/', 'customimages/', '/', parameters('customImageName'))]"
  },
  "resources": [
    {
      "apiVersion": "2017-04-26-preview",
      "type": "Microsoft.DevTestLab/labs/virtualmachines",
      "name": "[variables('vmName')]",
      "location": "[resourceGroup().location]",
      "properties": {
        "labVirtualNetworkId": "[variables('labVirtualNetworkId')]",
        "notes": "",
        "customImageId": "[variables('imageName')]",
        "size": "[parameters('size')]",
        "userName": "[parameters('userName')]",
        "password": "[parameters('password')]",
        "isAuthenticationWithSshKey": false,
        "labSubnetName": "[variables('labSubnetName')]",
        "disallowPublicIpAddress": false,
        "storageType": "Premium",
        "allowClaim": false
      }
    }
  ],
  "outputs": {
    "labVMId": {
      "type": "string",
      "value": "[variables('vmId')]"
    }
  }
}