The answer is the ability to continue operating despite component failures. This means a fault-tolerant system in cloud computing is designed to absorb hardware or software failures without any interruption to service, typically by deploying redundant components—such as multiple servers, network paths, or power supplies—so that if one element fails, another instantly takes over. On the Microsoft Azure Fundamentals AZ-900 exam, this concept tests your understanding of how Azure achieves resilience through features like Availability Zones and redundant infrastructure, and it is often contrasted with high availability, which allows for brief downtime. A common trap is confusing the two: remember that high availability aims for minimal downtime, while fault tolerance demands zero downtime even during a failure. A useful memory tip is to think of fault tolerance as a “no-break” system—like a car with a spare tire already spinning—so the ride never stops.
AZ-900 Describe cloud concepts Practice Question
This AZ-900 practice question tests your understanding of describe cloud concepts. Read the scenario carefully and evaluate each option against the stated constraints before committing to an answer. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.
What does the term 'fault tolerance' mean in cloud computing?
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
The ability to continue operating despite component failures
Fault tolerance is the ability of a system to continue operating without interruption when one or more of its components fail. In Azure, this is achieved through redundancy at multiple layers—such as using Availability Zones or redundant hardware—so that a failure in a single server, network path, or power supply does not bring down the entire workload. This is distinct from high availability, which focuses on minimizing downtime, whereas fault tolerance aims for zero downtime even during failures.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
✗
The ability to scale resources up and down automatically
Why it's wrong here
Automatic scaling is elasticity, not fault tolerance.
✓
The ability to continue operating despite component failures
Why this is correct
Fault tolerance means the system remains functional even when individual components fail, through redundancy and failover.
Related concept
Read the scenario before looking for a memorised answer.
✗
The ability to recover data after accidental deletion
Why it's wrong here
Data recovery after deletion is backup/restore capability, not fault tolerance.
✗
The ability to deploy applications across multiple regions
Why it's wrong here
Multi-region deployment supports both high availability and disaster recovery but is not the definition of fault tolerance.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates often confuse 'fault tolerance' with 'high availability' or 'disaster recovery', but the key differentiator is that fault tolerance implies zero downtime and no data loss during a failure, whereas high availability may involve a brief interruption and disaster recovery involves a longer recovery time objective (RTO).
Detailed technical explanation
How to think about this question
Under the hood, fault tolerance in Azure often relies on redundant arrays of independent disks (RAID), redundant power supplies, and network paths, combined with software-defined networking and load balancers that automatically detect and reroute traffic away from failed nodes. For example, Azure Virtual Machines deployed in an Availability Set use fault domains and update domains to ensure that VMs are placed on separate physical hardware and power sources, so a single rack failure does not affect all VMs. A real-world scenario is a mission-critical SQL Server Always On availability group that uses synchronous replication across two Azure Availability Zones—if one zone suffers a total power loss, the database continues to serve reads and writes from the other zone with zero data loss.
KKey Concepts to Remember
Read the scenario before looking for a memorised answer.
Find the constraint that changes the correct option.
Eliminate answers that are true in general but not in this case.
TExam Day Tips
→Watch for words such as best, first, most likely and least administrative effort.
→Review why wrong options are wrong, not only why the correct option is correct.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
How this comes up in practice
An e-commerce site experiences heavy traffic on Black Friday and near-zero traffic during off-peak weeks. Rather than provisioning permanent large VMs, the team uses auto-scaling groups that add capacity automatically under load and reduce it overnight. Questions like this test whether you understand elasticity, availability zones, and cloud compute scaling patterns.
Related glossary terms
Concepts from this question explained
These glossary pages explain the core terms tested in this AZ-900 question in full detail.
Describe cloud concepts — This question tests Describe cloud concepts — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: The ability to continue operating despite component failures — Fault tolerance is the ability of a system to continue operating without interruption when one or more of its components fail. In Azure, this is achieved through redundancy at multiple layers—such as using Availability Zones or redundant hardware—so that a failure in a single server, network path, or power supply does not bring down the entire workload. This is distinct from high availability, which focuses on minimizing downtime, whereas fault tolerance aims for zero downtime even during failures.
What should I do if I get this AZ-900 question wrong?
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
What is the key concept behind this question?
Read the scenario before looking for a memorised answer.
About these practice questions
Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →
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. What is 'fault tolerance' in cloud computing?
easy
A.The ability to automatically scale resources during peak usage
✓ B.The ability to continue operating correctly despite component failures
C.The ability to restore data after a major disaster
D.The ability to deploy applications in multiple geographic regions
Why B: Fault tolerance in cloud computing refers to a system's ability to continue operating correctly, without interruption, even when one or more of its components fail. This is achieved through redundancy—such as duplicate hardware, software, or data paths—so that if a component fails, another automatically takes over without any impact on the user. It is a core design principle for high-availability systems, ensuring zero downtime despite failures.
Last reviewed: Jun 11, 2026
Question Discussion
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
This AZ-900 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-900 exam.
Question Discussion
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
Sign in to join the discussion.