The Azure Custom Script Extension is designed to download and execute scripts on Azure

virtual machines after they are provisioned. This is ideal for post-deployment configuration

tasks, such as installing software like NGINX. When deploying a virtual machine scale set

using an Azure Resource Manager (ARM) template, the Custom Script Extension can be

included in the template to ensure that NGINX is installed on all instances automatically.

A. the Publish-AzVMDscConfiguration cmdlet: This cmdlet is used to package and publish a

PowerShell Desired State Configuration (DSC) script, which is part of using Azure

Automation DSC or the DSC extension. While DSC can install software, the cmdlet itself is

a preparatory step, not the direct mechanism used within the ARM template for execution

on the VMs. The Custom Script Extension is more direct for this specific task.

B. Azure Application Insights: This is an Application Performance Management (APM)

service used for monitoring applications, not for installing software on virtual machines.

D. a Microsoft Endpoint Manager device configuration profile: Microsoft Endpoint Manager

(formerly Intune) is primarily for managing client devices and mobile endpoints. It's not the

standard tool for configuring server software on Azure VMs within a scale set during ARM

template deployment.

Azure Custom Script Extension:

Microsoft Learn: "Custom Script Extension for Windows." "The Custom Script Extension

downloads and executes scripts on Azure virtual machines. This extension is useful for post

deployment configuration, software installation, or any other configuration / management

task."

URL: https://learn.microsoft.com/en-us/azure/virtual-machines/extensions/custom-scriptwindows

Microsoft Learn: "Tutorial: Install applications in Virtual Machine Scale Sets with an Azure

Resource Manager template." This tutorial demonstrates using the Custom Script Extension

to install a web server (IIS, but the principle applies to NGINX).

URL: https://learn.microsoft.com/en-us/azure/virtual-machine-scale-sets/tutorial-installapps-template (Section: "Use Custom Script Extension")

Azure Desired State Configuration (for option A context):

Microsoft Learn: "Introduction to Azure Desired State Configuration."

URL: https://learn.microsoft.com/en-us/azure/automation/dsc-overview

Azure Application Insights (for option B context):

Microsoft Learn: "What is Application Insights?"

URL: https://learn.microsoft.com/en-us/azure/azure-monitor/app/app-insights-overview

Microsoft Endpoint Manager (for option D context):

Microsoft Learn: "What is Microsoft Intune?" (Intune is part of Microsoft Endpoint Manager)

URL: https://learn.microsoft.com/en-us/mem/intune/fundamentals/what-is-intune