AZ-900 Practice Question 5: Virtual Machine Scale Sets
Microsoft Azure Fundamentals (AZ-900) · Test 1 · question 5 of 10
An online store runs its web tier on identical Azure virtual machines. Traffic triples every weekday evening and falls away overnight, and the operations team is tired of manually creating and deleting VMs. They need identical VM instances added and removed automatically as load changes, without rewriting the application. What should they use?
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Answer:
Virtual Machine Scale Sets let you create and manage a group of load-balanced, identical VMs and change the instance count automatically in response to demand or on a schedule. That is exactly the "add and remove identical VMs for me" requirement, and because the instances are still ordinary VMs the existing application runs unchanged.
Option A, an availability set, is a high-availability construct: it spreads VMs across fault and update domains so that hardware failure or host maintenance does not take them all down at once. It does not create or delete instances, so it solves availability, not scale. Option B, Azure Virtual Desktop, is a desktop and app virtualization service for delivering Windows sessions to end users, the wrong product category entirely. Option D, Azure Functions, does scale automatically, but it is an event-driven serverless compute model; moving a web tier onto it would mean rewriting the application, which the stem rules out.
Reference: What are Virtual Machine Scale Sets?