220-1101 Virtualization and Cloud Computing Practice Test 2 — 15 Questions

Question 1

A company runs a web application on a public cloud platform. The application often experiences variable traffic, with usage spikes lasting only a few hours. The company wants to automatically increase the number of virtual machine instances when CPU utilization exceeds 70% and decrease them when utilization drops below 30%. Which characteristic of cloud computing does this capability BEST represent?

Accepted Answer

Rapid elasticity. The ability to automatically scale virtual machine instances up and down in response to CPU utilization thresholds (70% up, 30% down) is a direct example of rapid elasticity. This cloud characteristic allows resources to be provisioned and released elastically, often automatically, to match demand at any given time. The scenario describes a dynamic, automated scaling action, which is the core definition of rapid elasticity in cloud computing.

Answer

On-demand self-service

Answer

Resource pooling

Answer

Measured service

Question 2

A small business wants to develop and deploy a custom web application. They do not want to manage any underlying infrastructure, including servers, operating systems, or runtime environments. They want to simply upload their code and let the cloud provider handle scaling and maintenance. Which cloud service model BEST fits this requirement?

Accepted Answer

Platform as a Service (PaaS). Platform as a Service (PaaS) is the correct choice because it provides a complete development and deployment environment in the cloud, abstracting away the underlying infrastructure. The business can upload custom code without managing servers, OS, or runtime, and the cloud provider automatically handles scaling, patching, and maintenance. This directly matches the requirement to avoid infrastructure management while deploying a custom web application.

Answer

Infrastructure as a Service (IaaS)

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Software as a Service (SaaS)

Answer

Anything as a Service (XaaS)

Question 3

A startup is developing a new web application. They want to write code and deploy it without worrying about the underlying operating system, web server, or scaling. Which cloud service model should they choose?

Accepted Answer

Platform as a Service (PaaS). Platform as a Service (PaaS) provides a managed environment where developers can write and deploy code without managing the underlying OS, web server, or scaling. The cloud provider handles the runtime, middleware, and infrastructure, allowing the startup to focus solely on application code. This aligns with the requirement to avoid worrying about the operating system, web server, or scaling.

Answer

Infrastructure as a Service (IaaS)

Answer

Software as a Service (SaaS)

Answer

Desktop as a Service (DaaS)

Question 4

An administrator manages a virtualized environment running on a Type 1 hypervisor (VMware ESXi). The physical host has 64 GB of RAM. The sum of allocated memory to all running VMs is 80 GB, and the hypervisor is using memory ballooning to reclaim memory from VMs. A critical database VM is experiencing significant performance degradation. Which of the following is the MOST likely cause of the performance issue?

Accepted Answer

The database VM is experiencing memory starvation due to the hypervisor reclaiming memory via ballooning.. The physical host has only 64 GB of RAM, but the sum of allocated memory to all running VMs is 80 GB, which is a 25% overcommitment. VMware ESXi uses memory ballooning to reclaim memory from VMs by forcing the VM's balloon driver to allocate guest memory, which the hypervisor then reclaims for other VMs. The critical database VM is experiencing significant performance degradation because the hypervisor is reclaiming memory from it via ballooning, causing the VM to swap to disk (memory starvation), which severely impacts database performance.

Answer

The hypervisor is overcommitting CPU resources, causing contention.

Answer

The VM's virtual disk is on a slow network storage link.

Answer

The hypervisor has insufficient network bandwidth for inter-VM communication.

Question 5

A company hosts its customer relationship management (CRM) application on a single virtual machine (VM) in a public cloud. The VM is configured with a static private IP address that is used by a third-party service to send data to the application. During a scheduled hardware maintenance event, the cloud provider automatically migrates the VM to a different physical host. After the migration, the CRM application can no longer receive data from the third-party service. Which of the following cloud computing concepts was MOST likely not properly implemented?

Accepted Answer

High availability. The correct answer is B. High availability. The VM was migrated to a different physical host during maintenance, which is a normal high-availability operation. However, the static private IP address was not preserved or re-mapped after migration, causing the third-party service to lose connectivity. Proper high-availability implementation requires that the VM's IP address (or a floating IP) remains reachable after failover or migration, typically through mechanisms like virtual IPs, DNS updates, or cloud provider's elastic IP services.

Answer

Elasticity

Answer

Scalability

Answer

Resource pooling

Question 6

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?

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

Answer

On-demand self-service

Answer

Rapid elasticity

Question 7

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

Answer

Measured service billing that throttles the VM

Answer

Lack of scalability in the application design

Question 8

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

Answer

Measured service

Answer

On-demand self-service

Question 9

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)

Answer

Software as a Service (SaaS)

Answer

Desktop as a Service (DaaS)

Question 10

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

Answer

Measured service

Answer

Broad network access

Question 11

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

Answer

Memory ballooning

Answer

Swap file size

Question 12

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 correct answer is B because 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

Answer

Insufficient virtual RAM allocation

Answer

Network bandwidth contention

Question 13

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.

Answer

High availability

Answer

Fault tolerance

Answer

Scalability

Question 14

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.

Answer

Type 2 hypervisor

Answer

Container-based virtualization

Answer

Cloud-based hypervisor as a service

Question 15

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

Answer

Broad network access

Answer

Resource pooling