Review fixes

Author: Michael Bender

articles/load-balancer/load-balancer-multiple-virtual-machine-scale-set.md

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+---
+title: Add multiple Virtual Machine Scale Set instances behind one Azure Load Balancer 
+description: learn how to configure multiple Virtual Machine Scale Set instances behind a single Azure load Balancer 
+author: mbender-ms
+ms.author: mbender
+ms.service: load-balancer
+ms.topic: how-to 
+ms.date: 12/15/2022
+ms.custom: template-how-to
+---
+
+# Add multiple Virtual Machine Scale Set instances behind one Azure Load Balancer 
+
+In this article, you’ll learn how to configure multiple Virtual Machine Scale Set instances behind a single Azure Load Balancer.
+
+## Prerequisites
+
+# [Azure portal](#tab/azureportal)
+
+- An Azure account with an active subscription. [Create an account for free](https://azure.microsoft.com/free/?WT.mc_id=A261C142F)
+- Two or more [Virtual Machine Scale Sets](../virtual-machine-scale-sets/quick-create-portal.md)
+  - Ensure the upgrade policy is set to automatic.
+    - If manual upgrade policy is used, upgrade all virtual machine instances after attaching it to the load balancer.  
+- An existing [standard SKU load balancer](quickstart-load-balancer-standard-internal-portal.md) in the same subscription and virtual network as the Virtual Machine Scale Sets.
+  - The load balancer must also have a backend pool with health probes and load balancing rules attached.
+- Access to the Azure portal
+# [Azure CLI](#tab/azurecli/)
+
+- An Azure account with an active subscription. [Create an account for free](https://azure.microsoft.com/free/?WT.mc_id=A261C142F)
+- Two or more [Virtual Machine Scale Sets](../virtual-machine-scale-sets/quick-create-portal.md)
+  - Unsure that the upgrade policy is set to automatic.
+    - If manual upgrade policy is used, upgrade all virtual machine instances after attaching it to the load balancer.  
+- An existing [standard SKU load balancer](quickstart-load-balancer-standard-internal-portal.md) in the same subscription and virtual network as the Virtual Machine Scale Sets.
+  - The load balancer must also have a backend pool with health probes and load balancing rules attached.
+- Access to the Azure portal CLI
+
+> [!NOTE]
+> If you choose to use Azure CLI, you have can run AZ CLI in Azure Cloud Shell or as a local install. Review the following to ensure you are ready to use Azure CLI in the environment you choose. 
+
+- Use the Bash environment in [Azure Cloud Shell](../cloud-shell/quickstart.md)
+  [![Launch Cloud Shell in a new window](../../includes/media/cloud-shell-try-it/hdi-launch-cloud-shell.png)](https://shell.azure.com)
+- If you prefer to run CLI reference commands locally, [install](/cli/azure/install-azure-cli) the Azure CLI. If you're running on Windows or macOS, consider running Azure CLI in a Docker container. For more information, see [How to run the Azure CLI in a Docker container](/cli/azure/run-azure-cli-docker).
+
+  - If you're using a local installation, sign in to the Azure CLI by using the [az sign-in](/cli/azure/reference-index#az-login) command. To finish the authentication process, follow the steps displayed in your terminal. For other sign-in options, see [Sign in with the Azure CLI](/cli/azure/authenticate-azure-cli).
+
+  - When you're prompted, install the Azure CLI extension on first use. For more information about extensions, see [Use extensions with the Azure CLI](/cli/azure/azure-cli-extensions-overview).
+
+  - Run [az version](/cli/azure/reference-index?#az-version) to find the version and dependent libraries that are installed. To upgrade to the latest version, run [az upgrade](/cli/azure/reference-index?#az-upgrade).
+
+---
+
+## Add Virtual Machine Scale Set to an Azure Load Balancer’s backend pool 
+
+In this section, you’ll learn how to attach your Virtual Machine Scale Sets behind a single Azure Load Balancer.
+
+> [!NOTE] 
+> The following section assumes a virtual network named *myVnet* and an Azure Load Balancer named *myLoadBalancer* has been previously deployed. In addition, the following section assumes the backend pools are NIC based.  
+
+# [Azure portal](#tab/azureportal)
+
+1. Sign into the [Azure portal](https://portal.azure.com).
+1. In the search box at the top of the portal, enter **Load balancer**. Select **Load balancers** in the search results.
+1. Select your balancer from the list.
+1. In your load balancer's page, select **Backend pools** under **Settings**.
+1. Select your backend pool.
+1. In your backend pool's page, select **+ Add** under **IP configurations**
+1. Select the two Virtual Machine Scale Sets that you want to add to the backend pool.
+1. Select **Add** and **Save**.
+
+# [Azure CLI](#tab/azurecli/)
+
+1. Connect to your Azure subscription with Azure CLI.
+1. Add the first Virtual Machine Scale Set to a load balancer with [az vmss update](/cli/azure/vmss#az-vmss-update), and replace the values in brackets with the names of the resources in your configuration.
+
+    ```azurecli
+    
+    az vmss update\
+        --resource-group <resource-group> \
+        --name <vmss-name> \
+        --add  virtualMachineProfile.networkProfile.networkInterfaceConfigurations[0].ipConfigurations[0].loadBalancerBackendAddressPools "{'id':'/subscriptions/<SubscriptionID>/resourceGroups/<Resource Group> /providers/Microsoft.Network/loadBalancers/<Load Balancer Name>/backendAddressPools/<Backend address pool name >}" 
+    
+    ```
+This example deploys a Virtual Machine Scale Set with the following defined values:  
+
+- Virtual Machine Scale Set named *myVMSS*
+- Azure Load Balancer named *MyLB*
+- Load Balancer backend pool named *mybackend*
+- Resource group named *myResourceGroup*
+- Subscription ID named *SubscriptionID* 
+```azurecli
+
+az vmss update \ 
+    --resource-group myResourceGroup \
+    --name myVMSS \
+    --add virtualMachineProfile.networkProfile.networkInterfaceConfigurations[0].ipConfigurations[0].loadBalancerBackendAddressPools "{'id':'/subscriptions/SubscriptionID/resourceGroups/myResourceGroup /providers/Microsoft.Network/loadBalancers/MyLb/backendAddressPools/mybackend'}" 
+
+```
+
+1. Repeat the steps to attach your second Virtual Machine Scale Set to the backend pool of the Azure Load Balancer with `az vmss update`.
+
+---
+## Next steps
+
+In this article, you attached multiple Virtual Machine Scale Sets behind a single Azure load balancer.
+
+- [What is Azure Load Balancer?](load-balancer-overview.md)
+- [What are Azure Virtual Machine Scale Sets?](../virtual-machine-scale-sets/overview.md)