what if nested template limit

Author: mumian

articles/azure-resource-manager/templates/deploy-what-if.md

@@ -1,10 +1,8 @@
 ---
 title: Template deployment what-if
 description: Determine what changes will happen to your resources before deploying an Azure Resource Manager template.
-author: tfitzmac
 ms.topic: conceptual
-ms.date: 07/11/2022
-ms.author: tomfitz
+ms.date: 02/14/2023
 ms.custom: devx-track-azurepowershell, devx-track-azurecli
 ms.devlang: azurecli
 ---
@@ -20,6 +18,16 @@ To learn more about what-if, and for hands-on guidance, see [Preview Azure deplo
 
 [!INCLUDE [permissions](../../../includes/template-deploy-permissions.md)]
 
+## What-if limits
+
+What-if expands nested templates until these limits are reached:
+
+- 500 nested templates.
+- 800 resource groups in a cross resource-group deployment.
+- 5 minutes have been taken for expanding the nested templates.
+
+When one of the limits is reached, the remaining resources' [change type](#change-types) is set to **Ignore**.
+
 ## Install Azure PowerShell module
 
 To use what-if in PowerShell, you must have version **4.2 or later of the Az module**.
@@ -132,7 +140,7 @@ The what-if operation lists six different types of changes:
 
 - **Delete**: This change type only applies when using [complete mode](deployment-modes.md) for deployment. The resource exists, but isn't defined in the template. With complete mode, the resource will be deleted. Only resources that [support complete mode deletion](./deployment-complete-mode-deletion.md) are included in this change type.
 
-- **Ignore**: The resource exists, but isn't defined in the template. The resource won't be deployed or modified.
+- **Ignore**: The resource exists, but isn't defined in the template. The resource won't be deployed or modified. When you reach the limits for expanding nested templates, you will encounter this change type. See [What-if limits](#what-if-limits).
 
 - **NoChange**: The resource exists, and is defined in the template. The resource will be redeployed, but the properties of the resource won't change. This change type is returned when [ResultFormat](#result-format) is set to `FullResourcePayloads`, which is the default value.