Often you may want to use a resource from outside of the current resource group where a template is getting deployed. The most common case for this behavior is using a storage account or virtual network in an alternate resource group. This is often needed so that the deletion of the resource group which contains the virtual machines will not res…

Crossing Resource Groups.json

{
  "$schema": "http://schema.management.azure.com/schemas/2014-04-01-preview/deploymentTemplate.json",
  "contentVersion": "1.0.0.0",
  "parameters": {
      "virtualNetworkName": {
          "type": "string"
      },
      "virtualNetworkResourceGroup": {
          "type": "string"
      },
      "subnet1Name": {
          "type": "string"
      },
      "nicName": {
          "type": "string"
      }
  },
  "variables": {
      "vnetID": "[resourceId(parameters('virtualNetworkResourceGroup'), 'Microsoft.Network/virtualNetworks', parameters('virtualNetworkName'))]",
      "subnet1Ref": "[concat(variables('vnetID'),'/subnets/', parameters('subnet1Name'))]"
  },
  "resources": [
  {
      "apiVersion": "2015-05-01-preview",
      "type": "Microsoft.Network/networkInterfaces",
      "name": "[parameters('nicName')]",
      "location": "[parameters('location')]",
      "properties": {
          "ipConfigurations": [{
              "name": "ipconfig1",
              "properties": {
                  "privateIPAllocationMethod": "Dynamic",
                  "subnet": {
                      "id": "[variables('subnet1Ref')]"
                  }
              }
          }]
       }
  }]

}