220-1101 Virtualization and Cloud Computing Practice Test 3 — 15 Questions

Question 1

A company runs a customer-facing web application on a single virtual machine in a public cloud. After migrating to the cloud, users report that the application's response time varies significantly during the day, even though the VM's CPU and memory utilization stay below 50%. The cloud provider states that no resource limits are imposed on the VM. Which of the following cloud characteristics is MOST likely causing the performance variability?

Choose an answer to begin — your selection is scored in the full session.

Accepted Answer

Resource pooling. Resource pooling allows the cloud provider to dynamically allocate and reallocate physical resources (CPU, RAM, network bandwidth) among multiple tenants. Even though your VM shows low CPU/memory utilization, the underlying physical host's network I/O or storage throughput may be oversubscribed, causing contention during peak usage periods for other tenants on the same host. This shared infrastructure is the most likely cause of the observed performance variability, as the provider does not guarantee dedicated resources unless explicitly purchased.

Answer

Measured service

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On-demand self-service

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Rapid elasticity

Question 2

A company runs its customer relationship management (CRM) application on a single virtual machine (VM) in a public cloud IaaS environment. During the workday, the application's response time becomes highly variable and often slow, even though the VM's CPU and memory utilization rarely exceed 50%. The cloud provider states that the physical host is a shared multi-tenant server. Which cloud computing concept is MOST likely causing this performance degradation?

Accepted Answer

Resource pooling leading to the 'noisy neighbor' effect. The performance degradation is most likely due to resource pooling in a multi-tenant IaaS environment, where the 'noisy neighbor' effect occurs. Even though the VM's own CPU and memory utilization are low, another VM on the same physical host may be consuming shared resources like disk I/O or network bandwidth, causing contention. This is a classic symptom of a shared hypervisor where one tenant's workload starves others of critical I/O resources.

Answer

Rapid elasticity causing the VM to be moved between hosts

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Measured service billing that throttles the VM

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Lack of scalability in the application design

Question 3

A company is migrating its on-premises virtualized infrastructure to a public cloud IaaS provider. The on-premises VMs were configured with static private IP addresses that are hardcoded in legacy applications for licensing and integration purposes. After migration, the legacy applications fail because the IP addresses assigned to the VMs in the cloud are different from the original on-premises addresses. The cloud provider does not allow the customer to keep the same IP addresses without using additional services. Which cloud computing characteristic is MOST directly responsible for the IP address change?

Accepted Answer

Resource pooling. Resource pooling is the cloud characteristic where the provider's compute resources are pooled to serve multiple customers using a multi-tenant model, with physical and virtual resources dynamically assigned and reassigned according to customer demand. This means the customer has no control over the exact underlying IP addressing scheme; the provider assigns IP addresses from its own pool, which are different from the on-premises static IPs. The need for additional services (like VPN or IP address translation) to retain the original IPs is a direct consequence of resource pooling, as the provider cannot guarantee a specific IP address without breaking the shared, abstracted nature of the pool.

Answer

Rapid elasticity

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Measured service

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On-demand self-service

Question 4

A company wants to deploy a custom web application. They need full control over the operating system, middleware, and runtime environment, but they do not want to manage the underlying physical hardware, such as servers, storage, and networking equipment. Which cloud service model BEST meets this requirement?

Accepted Answer

Infrastructure as a Service (IaaS). Infrastructure as a Service (IaaS) provides virtualized computing resources over the internet, giving the customer full control over the operating system, middleware, and runtime environment while the cloud provider manages the underlying physical hardware (servers, storage, networking). This matches the requirement exactly, as the company retains administrative access to the OS and software stack without needing to manage physical infrastructure.

Answer

Platform as a Service (PaaS)

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Software as a Service (SaaS)

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Desktop as a Service (DaaS)

Question 5

A cloud service provider uses a Type 1 hypervisor to host multiple tenant virtual machines on a single physical server. This allows the provider to serve many customers from the same infrastructure while maintaining isolation. Which essential characteristic of cloud computing does this best represent?

Accepted Answer

Resource pooling. Resource pooling is the correct answer because a Type 1 hypervisor (bare-metal hypervisor) abstracts the physical server's CPU, memory, and storage into a shared resource pool that can be dynamically allocated to multiple tenant VMs. This allows the provider to serve many customers from the same physical infrastructure while maintaining logical isolation, which is the defining characteristic of resource pooling in cloud computing.

Answer

Rapid elasticity

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Measured service

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Broad network access

Question 6

A system administrator is configuring a virtual machine (VM) on a VMware ESXi host. The VM runs a critical database application that requires a guaranteed minimum amount of memory to perform well. The host has memory overcommitment enabled. Which setting should the administrator configure to ensure the VM always has at least 4 GB of physical memory available?

Accepted Answer

Memory reservation. A memory reservation guarantees that the ESXi host will allocate at least the specified amount of physical memory to the VM, even when memory overcommitment is enabled. This ensures the critical database application always has a minimum of 4 GB of physical RAM available, preventing performance degradation due to contention.

Answer

Memory limit

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Memory ballooning

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Swap file size

Question 7

A company hosts a web application on a single virtual machine in a public cloud IaaS environment. The application experiences intermittent slowdowns. The administrator checks the VM's performance metrics and notices that CPU and memory usage are low, but disk I/O latency spikes during the slowdowns. The cloud provider uses a shared storage system with multiple tenants. Which of the following is the MOST likely cause?

Accepted Answer

Storage performance variability due to the noisy neighbor effect. The scenario describes a shared storage system with multiple tenants, and the symptoms (low CPU/memory but high disk I/O latency spikes) point directly to the 'noisy neighbor' effect. In a multi-tenant IaaS environment, one tenant's heavy storage workload can saturate the shared storage controller or network, causing unpredictable latency for other tenants. This matches the intermittent slowdowns without local resource exhaustion.

Answer

VM throttling due to burstable CPU

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Insufficient virtual RAM allocation

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Network bandwidth contention

Question 8

A company runs an e-commerce website on a public cloud IaaS platform. During a flash sale, traffic spikes to 10 times the normal volume. The website automatically scales its resources to handle the increased load and returns to normal capacity after the sale, with no manual intervention required. Which cloud computing characteristic does this scenario BEST demonstrate?

Accepted Answer

Elasticity. Elasticity is the cloud characteristic that allows resources to automatically scale up during demand spikes and scale down when demand subsides, without manual intervention. In this scenario, the IaaS platform dynamically provisions additional compute and network resources to handle 10x traffic during the flash sale, then releases them afterward, which is the defining behavior of elasticity.

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High availability

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Fault tolerance

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Scalability

Question 9

An organization plans to consolidate its physical servers by running multiple virtual machines on a single host. The administrator needs to choose a hypervisor that offers the best performance and direct access to hardware resources for the VMs. The host server will only run the hypervisor and its VMs. Which of the following hypervisor types is the BEST choice for this scenario?

Accepted Answer

Type 1 hypervisor. A Type 1 hypervisor (bare-metal) runs directly on the host hardware without an underlying operating system, providing near-native performance and direct access to CPU, memory, and I/O resources. This is ideal for the scenario where the host server is dedicated solely to running the hypervisor and its VMs, as it minimizes overhead and maximizes resource efficiency.

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Type 2 hypervisor

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Container-based virtualization

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Cloud-based hypervisor as a service

Question 10

A small business hosts its e-commerce website on a public cloud IaaS platform. During a major promotional event, traffic to the website increases by 15 times its normal volume. The cloud platform automatically provisions additional virtual servers to handle the load and then deprovisions them after the event ends, without any manual intervention. Which essential characteristic of cloud computing does this scenario BEST demonstrate?

Accepted Answer

Rapid elasticity. The scenario describes the cloud platform automatically scaling virtual servers up and down in response to a 15x traffic spike, then deprovisioning them without manual intervention. This directly demonstrates rapid elasticity, which is the ability to dynamically scale resources out and in based on demand, a core characteristic defined by NIST SP 800-145.

Answer

On-demand self-service

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Broad network access

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Resource pooling

Question 11

A company wants to migrate its on-premises infrastructure to the cloud while retaining full control over network configuration, firewall rules, and security policies. The company does not want to manage physical servers, storage, or the underlying hypervisor. Which cloud service model BEST meets these requirements?

Accepted Answer

IaaS (Infrastructure as a Service). IaaS (Infrastructure as a Service) provides virtualized computing resources over the internet, allowing the company to manage network configurations, firewall rules, and security policies while the cloud provider handles physical servers, storage, and the hypervisor. This model gives the customer control over the operating system, middleware, and applications, but not the underlying physical infrastructure, directly matching the requirement to avoid managing physical hardware.

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SaaS (Software as a Service)

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PaaS (Platform as a Service)

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DaaS (Desktop as a Service)

Question 12

A company uses a public cloud IaaS provider. A developer needs to create a new virtual machine for testing. The developer logs into the cloud management console, selects the desired OS and size, and launches the VM. The VM is ready within minutes. No interaction with the cloud provider's staff is required. Which cloud computing characteristic does this best represent?

Accepted Answer

On-demand self-service. The scenario describes a user provisioning a virtual machine without any human interaction with the cloud provider, which is the defining characteristic of on-demand self-service. This capability is a core NIST definition of cloud computing, allowing users to automatically provision computing resources as needed without requiring service provider intervention.

Answer

Resource pooling

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Rapid elasticity

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Measured service

Question 13

A company wants to move its email system to the cloud. The cloud vendor provides the email service, including server hardware, operating system, and software. The company only needs to manage user accounts and mailboxes. Which cloud service model is the vendor providing?

Accepted Answer

Software as a Service (SaaS). The vendor provides the entire email service, including server hardware, operating system, and software, while the company only manages user accounts and mailboxes. This matches the Software as a Service (SaaS) model, where the provider delivers a complete application over the internet, and the customer has no control over the underlying infrastructure or platform.

Answer

Infrastructure as a Service (IaaS)

Answer

Platform as a Service (PaaS)

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Desktop as a Service (DaaS)

Question 14

A company wants to migrate its on-premises infrastructure to the cloud. The security team requires that the company retains full control over network configuration, firewall rules, and security policies, but they do not want to manage physical servers, storage, or the underlying hypervisor. Which cloud service model BEST meets these requirements?

Accepted Answer

Infrastructure as a Service (IaaS). Infrastructure as a Service (IaaS) provides virtualized computing resources over the internet, allowing the company to manage and control the network configuration, firewall rules, and security policies while the cloud provider handles the physical servers, storage, and hypervisor. This model gives the customer full control over the operating system, storage, and deployed applications, meeting the requirement of not managing the underlying physical infrastructure.

Answer

Software as a Service (SaaS)

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Platform as a Service (PaaS)

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Database as a Service (DBaaS)

Question 15

A company hosts a critical application on two virtual machines located in different availability zones within the same cloud region. Both VMs are active and running simultaneously. The application is designed such that if one VM fails, the other continues serving traffic without any downtime. Which cloud concept does this configuration BEST demonstrate?

Accepted Answer

Fault tolerance. This configuration demonstrates fault tolerance because the application is designed to continue operating without interruption when one VM fails. By running two active VMs in different availability zones within the same region, the system eliminates a single point of failure and ensures zero downtime during a component failure, which is the defining characteristic of fault tolerance.

Answer

Elasticity

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Load balancing

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Auto-scaling