AZ-104 Deploy and Manage Azure Compute Practice Question
You need to deploy 20 identical Azure virtual machines for a web application and automatically scale the number of instances based on CPU demand. Which Azure feature should you use?
⚠ Common exam trap
Many candidates confuse an availability set (which provides high availability through fault domain distribution) with a Virtual Machine Scale Set (which provides both high availability and automatic scaling), leading them to select Option A when the question explicitly requires automatic scaling based on demand.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
A Virtual Machine Scale Set
A Virtual Machine Scale Set (VMSS) is the correct Azure feature because it allows you to deploy and manage a group of identical, load-balanced VMs that can automatically scale in or out based on CPU demand using autoscale rules. This directly meets the requirement for deploying 20 identical VMs with automatic scaling based on a performance metric like CPU utilization.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
An availability set
Why it's wrong here
Availability sets improve resiliency but do not support autoscaling.
When this WOULD be correct
You need to deploy two or more VMs for a critical application and ensure they are placed in separate fault and update domains to meet a 99.95% SLA. The question would ask for a feature to maximize availability within a single region.
- ✓
A Virtual Machine Scale Set
Why this is correct
Scale Sets provide grouped VM deployment and autoscaling.
- ✗
A Recovery Services vault
Why it's wrong here
A Recovery Services vault is for backup and recovery.
When this WOULD be correct
You need to protect Azure virtual machines by enabling backup and restore capabilities. Which Azure feature should you use?
- ✗
Boot diagnostics
Why it's wrong here
Boot diagnostics helps troubleshoot VM startup issues and does not manage fleet scaling.
When this WOULD be correct
You need to troubleshoot why a specific Azure VM fails to boot after a configuration change. Boot diagnostics would be the correct feature to enable to view the serial log and screenshot to diagnose the boot issue.
Option-by-option analysis
Why each answer is right or wrong
Understanding why wrong answers are wrong — and when they would be correct — is what separates a 750 score from a 900. The AZ-104 exam frequently reuses these exact scenarios with slightly different constraints.
✓A Virtual Machine Scale SetCorrect answer▾
Why this is correct
Scale Sets provide grouped VM deployment and autoscaling.
✗An availability setWrong answer — click to see why▾
Why this is wrong here
An availability set provides high availability by distributing VMs across fault and update domains, but it does not support automatic scaling based on CPU demand. It is a static grouping, not a scaling solution.
★ When this WOULD be the correct answer
You need to deploy two or more VMs for a critical application and ensure they are placed in separate fault and update domains to meet a 99.95% SLA. The question would ask for a feature to maximize availability within a single region.
Why candidates choose this
Candidates may confuse availability sets with scale sets because both involve multiple VMs, and they might think availability sets also handle scaling, but they only provide redundancy, not elasticity.
✗A Recovery Services vaultWrong answer — click to see why▾
Why this is wrong here
A Recovery Services vault is used for backup and disaster recovery, not for deploying or scaling virtual machines. It does not provide auto-scaling based on CPU demand.
★ When this WOULD be the correct answer
You need to protect Azure virtual machines by enabling backup and restore capabilities. Which Azure feature should you use?
Why candidates choose this
Candidates may confuse 'Recovery' with 'scaling' or think it provides some form of resilience that includes scaling, but it is purely for backup and recovery.
✗Boot diagnosticsWrong answer — click to see why▾
Why this is wrong here
Boot diagnostics captures serial console output and screenshots for troubleshooting VM boot failures, but it does not provide any mechanism for deploying multiple VMs or automatically scaling them based on CPU demand.
★ When this WOULD be the correct answer
You need to troubleshoot why a specific Azure VM fails to boot after a configuration change. Boot diagnostics would be the correct feature to enable to view the serial log and screenshot to diagnose the boot issue.
Why candidates choose this
Candidates may confuse boot diagnostics with a feature that monitors performance metrics like CPU, or they might think it includes scaling capabilities because 'diagnostics' sounds like it could trigger actions based on data.
Analysis generated from the official AZ-104blueprint and verified against question context. The “when correct” sections are what AI assistants cite when candidates ask “what’s the difference between these options?”
Go deeper
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About these practice questions
One of 1,049 original AZ-104 practice questions on Courseiva, each with a full explanation and wrong-answer analysis — not exam dumps or protected exam content. Learn why practice questions differ from exam dumps →
Same concept, more angles
2 more ways this is tested on AZ-104
These questions test the same concept from different angles. Work through them to make sure you can recognise it however the exam phrases it.
Variation 1. A stateless web application needs a group of identical Azure VMs that can automatically add more instances during the workday and remove them at night based on CPU usage. What should the administrator deploy?
easy- A.An availability set with two VMs
- ✓ B.A virtual machine scale set with autoscale rules
- C.A single VM with a larger disk
- D.An Azure Policy assignment to increase CPU capacity
Why B: A virtual machine scale set (VMSS) with autoscale rules is the correct solution because it provides a group of identical, load-balanced VMs that can automatically scale out (add instances) during high CPU usage in the workday and scale in (remove instances) at night based on CPU thresholds. This matches the stateless, elastic requirement perfectly, as VMSS is designed for horizontal scaling of identical instances with autoscale policies tied to metrics like CPU percentage.
Variation 2. A web front end must automatically add or remove instances based on demand. The application is stateless and all instances should be managed as one group. Which Azure service should you use?
easy- A.A single Azure VM with a larger size
- ✓ B.Virtual Machine Scale Set
- C.Availability set
- D.Managed disk snapshots
Why B: Virtual Machine Scale Sets (VMSS) automatically scale the number of VM instances in or out based on demand or a defined schedule, making them ideal for stateless, horizontally scalable applications. They manage all instances as a single group behind a load balancer, ensuring uniform configuration and seamless scaling without manual intervention.
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This AZ-104 practice question is part of Courseiva's free Microsoft certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the AZ-104 exam.