AZ-900 Describe cloud concepts Practice Test 10 — 15 Questions

Question 1

A cloud provider uses virtualization technology to host multiple customers on the same physical server. Each customer's data, applications, and operating systems are logically isolated and secured from one another. Which characteristic of cloud computing does this scenario best describe?

Accepted Answer

Resource pooling. This scenario describes resource pooling, where the provider's computing resources (such as storage, memory, and network bandwidth) are pooled to serve multiple customers using a multi-tenant model. Virtualization technology creates isolated virtual machines for each tenant, ensuring logical separation of data and applications while sharing the same physical hardware. This is a core characteristic of cloud computing as defined by NIST SP 800-145.

Answer

Rapid elasticity

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Measured service

Answer

On-demand self-service

Question 2

A company migrates its web application to Azure. The CFO wants to view detailed reports of CPU usage, storage consumption, and network bandwidth for each team's resources to accurately allocate costs. The company uses Azure Cost Management and Billing to generate these reports. Which characteristic of cloud computing does this capability best illustrate?

Accepted Answer

Measured service. Measured service is the cloud characteristic that enables providers to track and report resource usage (CPU, storage, bandwidth) for billing and cost allocation. Azure Cost Management and Billing leverages this capability by aggregating consumption metrics from Azure Monitor and resource providers, then generating detailed reports that allow the CFO to allocate costs per team. Without measured service, granular usage-based billing and cost attribution would not be possible.

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Rapid elasticity

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Resource pooling

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On-demand self-service

Question 3

A company hosts a web application on Azure App Service. The application must be accessible from any internet-connected device, including smartphones and laptops. Employees also use the Azure portal and Azure CLI from various locations to manage the application and other Azure resources. This scenario best illustrates which characteristic of cloud computing?

Accepted Answer

Broad network access. Broad network access is the correct characteristic because the scenario explicitly describes the web application being accessible from any internet-connected device (smartphones, laptops) and employees managing resources via the Azure portal and CLI from various locations. This aligns with the NIST definition of broad network access, where resources are available over the network and accessed through standard protocols (e.g., HTTPS, SSH) by heterogeneous thin or thick client platforms.

Answer

On-demand self-service

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Resource pooling

Answer

Measured service

Question 4

A company runs a web application on a set of Azure virtual machines. The application experiences unpredictable spikes in user traffic. The company configures an Azure Virtual Machine Scale Set with an autoscale rule that adds virtual machines when CPU usage exceeds 75% and removes virtual machines when CPU usage drops below 30%. This ability to automatically adjust compute resources to match demand best represents which characteristic of cloud computing?

Accepted Answer

Elasticity. Elasticity is the ability of a cloud system to automatically scale resources up or down to match demand. In this scenario, the Azure Virtual Machine Scale Set dynamically adds VMs when CPU exceeds 75% and removes them when CPU drops below 30%, directly demonstrating elasticity. This ensures the application has sufficient compute capacity during traffic spikes and avoids over-provisioning during low usage.

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High availability

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Fault tolerance

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Disaster recovery

Question 5

A company runs its production workloads on an on-premises data center to meet strict regulatory compliance requirements. However, the development and testing teams use Azure to quickly provision environments on demand for short-term projects. The teams need to occasionally transfer data between the on-premises environment and Azure. Which cloud deployment model does this setup represent?

Accepted Answer

Hybrid cloud. This setup combines an on-premises data center (private cloud) with Azure (public cloud) to form a hybrid cloud. The hybrid cloud model allows workloads to remain on-premises for compliance while leveraging Azure's elasticity for dev/test, with data transfer bridging both environments.

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Public cloud

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Private cloud

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Community cloud

Question 6

A company historically purchased physical servers and networking equipment for its data center, paying the full cost upfront before using the hardware. The company is now migrating its workloads to Azure and will only pay for the compute and storage resources it consumes each month, with no long-term commitments or upfront hardware purchases. This financial model change best represents which cloud computing benefit?

Accepted Answer

Consumption-based pricing. The scenario describes a shift from upfront capital expenditure (CapEx) for physical hardware to a model where the company pays only for the resources it consumes each month, without long-term commitments. This directly aligns with consumption-based pricing, a core Azure benefit where costs are incurred based on actual usage of compute, storage, and other services, eliminating the need for upfront hardware purchases.

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High availability

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Elasticity

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Disaster recovery

Question 7

A company runs a critical web application on Azure virtual machines. To ensure the application remains accessible even if an entire Azure datacenter becomes unavailable due to a power outage, the company deploys virtual machines in two different Azure regions and uses Azure Traffic Manager to automatically route traffic to the healthy region. Which benefit of cloud computing does this configuration primarily demonstrate?

Accepted Answer

High availability. This configuration demonstrates high availability because it uses Azure Traffic Manager to route traffic across two Azure regions, ensuring the application remains accessible even if an entire datacenter fails. High availability focuses on minimizing downtime by eliminating single points of failure, which is exactly what deploying VMs in multiple regions with traffic routing achieves.

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Elasticity

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Cost reduction

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Security

Question 8

A manufacturing company traditionally relied on an internal IT team to procure, configure, and install physical servers for each new project. The provisioning process typically took three to four weeks. After migrating to Azure, developers can now provision virtual machines and other resources directly from the Azure portal within minutes without any interaction with the IT team. This capability best represents which characteristic of cloud computing?

Accepted Answer

On-demand self-service. The scenario describes users provisioning virtual machines directly from the Azure portal without IT intervention. This aligns with on-demand self-service, a core cloud characteristic defined by NIST SP 800-145, where a consumer can unilaterally provision computing capabilities as needed automatically without requiring human interaction with each service provider.

Answer

Rapid elasticity

Answer

Measured service

Answer

Resource pooling

Question 9

A company migrates its on-premises infrastructure to Azure. The IT manager notes that Azure dynamically allocates and reallocates compute and storage resources across multiple customers based on demand, while ensuring each customer's data and workloads remain isolated from others. Which cloud computing characteristic does this describe?

Accepted Answer

Resource pooling. Resource pooling is the cloud computing characteristic where the provider's computing resources are pooled to serve multiple customers using a multi-tenant model, with physical and virtual resources dynamically assigned and reassigned according to demand. This ensures each customer's data and workloads remain isolated while the provider can efficiently allocate compute and storage across tenants. The scenario directly describes this multi-tenant isolation and dynamic allocation, which is the essence of resource pooling.

Answer

Rapid elasticity

Answer

Measured service

Answer

On-demand self-service

Question 10

A company plans to migrate a line-of-business application to Azure virtual machines (IaaS). The company's security team is reviewing the shared responsibility model to determine which security tasks are handled by Microsoft. Which of the following security responsibilities belongs to Microsoft?

Accepted Answer

Maintaining physical security of the datacenter where the servers are hosted. Under the shared responsibility model for IaaS, Microsoft is responsible for the physical security of its datacenters, including access controls, surveillance, and environmental safeguards. This is a foundational layer that customers cannot manage, making option C correct.

Answer

Configuring operating system firewalls on the virtual machines

Answer

Patching the guest operating system of the virtual machines

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Managing application-level user authentication and authorization

Question 11

A company is developing a new web application. The development team wants to deploy the application code without having to manage the underlying virtual machines, operating systems, or runtime environments. They only want to focus on writing code and let the cloud provider handle the infrastructure, platform, and scaling automatically. Which cloud service model does this scenario describe?

Accepted Answer

Platform as a Service (PaaS). This scenario describes Platform as a Service (PaaS) because the development team wants to deploy application code without managing the underlying virtual machines, operating systems, or runtime environments. PaaS provides a managed hosting environment where the cloud provider handles infrastructure, platform updates, and automatic scaling, allowing developers to focus solely on writing and deploying code. In contrast, IaaS would require managing VMs and OS, while SaaS delivers fully built applications, not a platform for custom code deployment.

Answer

Infrastructure as a Service (IaaS)

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Software as a Service (SaaS)

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Function as a Service (FaaS)

Question 12

A company runs a legacy application on-premises that must store data within the country due to regulatory requirements. To handle occasional peak workloads, the company connects its local network to an Azure virtual network via a site-to-site VPN. During these peaks, the application scales out to Azure virtual machines that process compute tasks but never store regulated data outside the on-premises datacenter. Which cloud deployment model does this scenario best describe?

Accepted Answer

Hybrid cloud. Option C is correct because the scenario combines an on-premises private infrastructure (the legacy application and regulated data) with Azure public cloud resources (virtual machines for compute scaling) connected via a site-to-site VPN. This integration of private and public resources to handle variable workloads while maintaining data sovereignty defines a hybrid cloud deployment model.

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Public cloud

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Private cloud

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Community cloud

Question 13

A retail company runs an e-commerce application on Azure. During the holiday season, the application experiences a sudden 10x increase in traffic. The company uses Azure Virtual Machine Scale Sets configured with autoscale rules based on CPU usage. The application automatically adds virtual machines during the peak and removes them when traffic subsides. Which benefit of cloud computing does this configuration primarily demonstrate?

Accepted Answer

Elasticity. This configuration demonstrates elasticity, which is the ability of a cloud system to automatically scale resources up or down based on demand. Azure Virtual Machine Scale Sets with autoscale rules based on CPU usage dynamically add VMs during traffic spikes and remove them when traffic subsides, directly matching resource allocation to workload requirements. This is a core benefit of cloud computing that enables cost efficiency and performance optimization without manual intervention.

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High availability

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Fault tolerance

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Latency-based routing

Question 14

A manufacturing company traditionally purchased and maintained its own servers, paying a large upfront capital expense (CapEx) for hardware that was expected to last five years. After migrating its workloads to Azure virtual machines, the company now receives a monthly invoice that reflects only the compute and storage resources actually consumed during that month. There are no upfront payments. This change in cost structure best illustrates which benefit of cloud computing?

Accepted Answer

Consumption-based pricing model. The scenario describes a shift from a large upfront capital expenditure (CapEx) for hardware to a monthly invoice based on actual compute and storage consumption. This directly illustrates the consumption-based pricing model, where you pay only for the resources you use (e.g., VM hours, storage GB-months) with no upfront costs. This is a core financial benefit of cloud computing, enabling operational expenditure (OpEx) instead of CapEx.

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Scalability to handle variable demand

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High availability through geographic redundancy

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Resource pooling through multi-tenancy

Question 15

A manufacturing company deploys a batch processing application on Azure. The processing workload is highly unpredictable; sometimes the application requires hundreds of virtual machines for a few hours to process a large queue of jobs, and at other times it requires only a handful of virtual machines. The company configures the application to automatically add and remove virtual machines based on the size of the processing queue, ensuring that they never pay for idle capacity. Which cloud characteristic does this scenario primarily demonstrate?

Accepted Answer

Elasticity. The scenario describes automatically scaling the number of virtual machines up and down based on the queue size, which directly aligns with the cloud characteristic of elasticity. Elasticity allows resources to be dynamically provisioned and de-provisioned to match workload demand, ensuring the company never pays for idle capacity. This is distinct from high availability, fault tolerance, or disaster recovery, which focus on uptime, redundancy, and data protection rather than dynamic scaling.

Answer

High availability

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Fault tolerance

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Disaster recovery