CV0-004 Cloud Architecture and Design — Timed 40 Questions

Question 1

A company uses an auto-scaling group to handle variable web traffic. The scaling policy is based on CPU utilization. However, during a flash sale, the application experiences a sudden spike in traffic, and the auto-scaling group takes too long to launch new instances. Which design change would most effectively reduce the time to scale out?

40 minute time limit — choose an answer to begin.

Accepted Answer

Use scheduled scaling to pre-warm instances before the sale. Using a predictive scaling policy or scheduled scaling can anticipate traffic spikes and pre-warm instances, reducing launch delay. Alternatively, increasing the cooldown period would slow scaling. Lowering the threshold would cause earlier scaling but not necessarily reduce launch time. Using larger instances is vertical scaling, not addressing launch delay.

Answer

Use larger instance types to handle more traffic

Answer

Lower the CPU utilization threshold

Answer

Increase the cooldown period

Question 2

A company needs to choose a disaster recovery strategy with an RTO of 4 hours and an RPO of 15 minutes. Which of the following is the most cost-effective approach that meets these requirements?

Accepted Answer

Pilot light. Pilot light keeps a minimal environment running and can be scaled up quickly; it offers a balance between cost and recovery time. Warm standby would be more expensive, cold standby would not meet RTO/RPO, and multi-site active-active is overkill.

Answer

Multi-site active-active

Answer

Warm standby

Answer

Cold standby

Question 3

A financial services firm requires low latency between on-premises resources and its public cloud VPC. They also need a dedicated, consistent network connection that bypasses the internet. Which connectivity option should they use?

Accepted Answer

Direct Connect / ExpressRoute. Direct Connect (AWS) or ExpressRoute (Azure) provides a dedicated, private network connection between on-premises infrastructure and the cloud provider's network, bypassing the public internet entirely. This delivers consistent low latency, higher bandwidth, and improved security compared to internet-based connections. For a financial services firm requiring predictable performance and dedicated connectivity, this is the appropriate solution.

Answer

Cloud CDN

Answer

Internet gateway

Answer

Site-to-Site VPN

Question 4

A cloud architect is designing a multi-region application with a Recovery Time Objective (RTO) of 1 hour and a Recovery Point Objective (RPO) of 15 minutes. The application runs on virtual machines in a public cloud. Which disaster recovery strategy best meets these objectives?

Accepted Answer

Hot standby in a secondary region with synchronous replication. Hot standby involves running a fully functional standby environment that can take over within minutes, achieving low RTO and RPO. Active-active can also meet these but may be more complex and costly; warm standby typically has longer RTO; cold standby has hours.

Answer

Active-active across two regions with load balancing

Answer

Cold standby with daily backups

Answer

Warm standby with hourly snapshots

Question 5

A healthcare organization must store patient imaging data that is accessed infrequently but must be retained for 7 years. They need the lowest-cost storage option while ensuring data can be retrieved within 12 hours if needed. Which storage class should they use?

Accepted Answer

Archive storage (Glacier / Azure Archive). Archive storage tiers (AWS S3 Glacier Deep Archive, Azure Archive) are designed for long-term retention of infrequently accessed data at the lowest cost per GB, with retrieval times measured in hours — well within the 12-hour requirement. For 7-year healthcare retention with rare access, archive is the cost-optimal choice that still meets the retrieval SLA.

Answer

Object storage standard tier

Answer

Block storage with snapshots

Answer

File storage (EFS / Azure Files)

Question 6

An organization maintains a private cloud using OpenStack and also uses AWS for additional capacity. They have a critical application that must remain available even if one cloud provider goes offline. The application is deployed in both environments with active load balancing. Which cloud deployment model best describes this architecture?

Accepted Answer

Hybrid cloud. The architecture uses both a private cloud (OpenStack) and a public cloud (AWS) with active load balancing to ensure availability even if one provider fails. This is the defining characteristic of a hybrid cloud, which integrates private and public cloud resources while maintaining orchestration between them.

Answer

Multi-cloud

Answer

Public cloud

Answer

Private cloud

Question 7

A cloud architect is designing a solution for a financial analytics application that requires consistent, low-latency block storage for a database. The database will be deployed on a virtual machine in a public cloud. Which TWO storage types are appropriate for this requirement? (Select TWO.)

Accepted Answer

Block storage (EBS / Azure Disk). Option A, block storage such as Amazon EBS or Azure Disk, is correct because it provides persistent, low-latency block-level volumes that can be attached to a VM and used directly by a database, offering consistent IOPS and throughput suitable for financial analytics workloads. Option D, instance store, is also correct because it delivers locally attached, high-performance block storage with very low latency, which is appropriate for a database VM when the workload can tolerate its ephemeral nature or when data is replicated elsewhere. Option B, file storage like EFS or Azure Files, is not ideal because it is a shared network file system with higher and less predictable latency than dedicated block devices. Option C, archive storage, is designed for long-term retention and retrieval, not for active low-latency database I/O. Option E, object storage, is accessed via HTTP APIs and is not suitable as a low-latency block device for a database.

Answer

File storage (EFS / Azure Files)

Answer

Archive storage

Answer

Object storage

Question 8

A company is migrating its on-premises application to a public cloud. The application consists of a web server, an application server, and a database. They want to minimize management overhead while ensuring the application can scale automatically. Which THREE cloud service models should they consider for each component to achieve this goal? (Select THREE.)

Accepted Answer

PaaS for database. For web server: PaaS (e.g., AWS Elastic Beanstalk) can manage the runtime and scaling. For application server: PaaS also works. For database: PaaS (e.g., Amazon RDS) provides managed database with auto-scaling. IaaS would require more management of OS and scaling. SaaS is complete application, not appropriate for custom components. FaaS could be used but is more granular.

Answer

SaaS for database

Answer

IaaS for web server

Question 9

A cloud architect is designing a cost-optimized architecture for a batch processing workload that runs every hour for 10 minutes. The workload is fault-tolerant and can be interrupted. Which TWO pricing models should the architect consider to minimize costs? (Select TWO.)

Accepted Answer

On-demand instances. On-demand instances (C) are correct because they allow the architect to pay only for the compute capacity used per hour, with no upfront commitment, which is ideal for a short-duration (10-minute) batch workload that runs every hour. Spot instances (D) are correct because the workload is fault-tolerant and can be interrupted, enabling the use of spare cloud capacity at significantly discounted rates (often 60-90% off on-demand), further minimizing costs for this interruptible batch processing task.

Answer

Dedicated hosts

Answer

Savings plans

Answer

Reserved instances

Question 10

A company runs a web application on AWS EC2 instances behind an Application Load Balancer. They want to handle traffic spikes automatically. Which scaling approach should they implement?

Accepted Answer

Auto-scaling. Auto-scaling automatically adjusts the number of EC2 instances in response to demand, which is the correct approach for handling unpredictable traffic spikes behind an ALB. AWS Auto Scaling groups integrate directly with the ALB target group and CloudWatch metrics to add or remove instances based on policies. This provides elasticity without manual intervention.

Answer

Vertical scaling

Answer

Manual scaling

Answer

Horizontal scaling

Question 11

A cloud architect is designing a VPC with public and private subnets. Which component is required to allow instances in the private subnet to access the internet for software updates?

Accepted Answer

NAT gateway. A NAT gateway is required to enable instances in a private subnet to initiate outbound connections to the internet (e.g., for software updates) while preventing the internet from initiating inbound connections to those instances. It translates the private IP addresses of the instances to the NAT gateway's Elastic IP address using source network address translation (SNAT). An Internet gateway alone cannot serve private subnets because it requires a route table entry pointing to a public subnet with a public IP address.

Answer

Elastic IP

Answer

VPN connection

Answer

Internet gateway

Question 12

A company deploys a multi-region active-active application on AWS. They use Route 53 with a latency routing policy. Traffic from Europe is routed to the eu-west-1 region, but during a regional failure, some European users experience timeouts. Which routing policy should be added to improve availability?

Accepted Answer

Latency-based routing with health checks and failover. Combining latency with failover routing provides automatic failover to a healthy region.

Answer

Geolocation routing

Answer

Failover routing

Answer

Weighted routing

Question 13

A company is deploying a web application that requires high availability across two geographically separate data centers. The application must be active in both sites simultaneously, and traffic must be load-balanced between them. Which architecture best meets these requirements?

Accepted Answer

Active-active architecture. An active-active architecture runs the application simultaneously in both geographically separate data centers, with both sites actively serving traffic. This directly satisfies the requirement for the application to be active in both sites at the same time. Load balancing distributes incoming requests across both sites, providing high availability and efficient resource utilization. If one site fails, the other continues to handle the full load, ensuring continuous service.

Answer

Active-passive architecture

Answer

Fault-tolerant N+1 architecture

Answer

Warm standby architecture

Question 14

A cloud architect is designing a multi-region application on AWS. The application has a critical database that must tolerate the failure of an entire AWS region. Which strategy provides the lowest RTO while ensuring data consistency?

Accepted Answer

Active-passive with synchronous replication. Active-passive with synchronous replication provides the lowest RTO for regional failure because the standby region has up-to-date data and can be promoted quickly, though synchronous replication may impact performance. Active-active requires conflict resolution. Asynchronous replication has higher RPO. Multi-cloud adds complexity and latency.

Answer

Active-active with asynchronous replication

Answer

Active-passive with asynchronous replication

Answer

Multi-cloud active-active with eventual consistency

Question 15

A company wants to migrate a legacy application to the cloud. The application has a monolithic design and requires low-latency access to on-premises databases. The company needs to keep sensitive data on-premises due to regulatory compliance. Which cloud deployment model is most suitable?

Accepted Answer

Hybrid cloud. A hybrid cloud combines on-premises infrastructure with public cloud resources, allowing the company to keep sensitive data on-premises for regulatory compliance while leveraging cloud scalability and services for the application tier. It also supports low-latency connectivity to on-premises databases via dedicated links such as AWS Direct Connect or VPN.

Answer

Public cloud

Answer

Multi-cloud

Answer

Private cloud

Question 16

A cloud engineer is designing a VPC in AWS for a three-tier web application. The web servers must be accessible from the internet, the application servers must be isolated from the internet but reachable by web servers, and the database servers must be isolated from both. How many subnets should be created, and which type should each be?

Accepted Answer

Three subnets: public for web, private for app, and private for database with stricter security groups. A three-tier architecture typically uses three subnets: public for web servers, private for application servers, and a database subnet (often private with additional restrictions). The database subnet is typically private, but the question asks for isolation, implying a separate subnet tier. A single subnet cannot provide isolation. Two subnets would combine two tiers, violating isolation.

Answer

Two subnets: public for web, private for app and database together

Answer

One public subnet for all tiers

Answer

Four subnets: two public for redundancy, two private for app and database

Question 17

A company runs a stateless web application on AWS EC2 instances behind an Application Load Balancer. The application experiences varying traffic patterns, with spikes on weekdays. The company wants to minimize costs while ensuring performance during spikes. Which combination of purchasing options and scaling strategy is most cost-effective?

Accepted Answer

Reserved instances for baseline capacity and on-demand instances for spikes. Reserved instances provide a significant discount (up to 72%) compared to On-Demand for steady-state baseline capacity, which is predictable. For traffic spikes, On-Demand instances offer flexibility without long-term commitment and can be launched quickly to handle increased load, ensuring performance. This combination minimizes cost while maintaining performance during spikes.

Answer

Spot instances for all capacity with a large buffer

Answer

On-demand instances for baseline and reserved instances for spikes

Answer

Reserved instances for baseline capacity and spot instances for spikes

Question 18

A company is migrating a legacy application to the cloud. The application has a stateful design and requires low-latency access to a shared file system. The application must scale horizontally to handle increased load. Which THREE of the following architectural changes should be recommended to enable horizontal scaling?

Accepted Answer

Refactor the application to be stateless. Horizontal scaling requires that any instance can handle any request without depending on local state. By refactoring the application to be stateless, session data is externalized, allowing new instances to be added or removed without affecting ongoing transactions. This eliminates the coupling between a client and a specific server, which is essential for elastic scaling in cloud environments.

Answer

Increase the size of the existing virtual machines (vertical scaling)

Answer

Use sticky sessions (session affinity) on the load balancer

Question 19

A company uses a public cloud IaaS model to host a database. They want to ensure the database remains available if an entire availability zone fails. Which configuration would provide the highest availability with automatic failover?

Accepted Answer

Deploy the database with a stand-by replica in a different availability zone using synchronous replication. Deploying a database with a stand-by replica in a different availability zone using synchronous replication ensures that all committed transactions are written to both the primary and the stand-by before acknowledging the client. This provides automatic failover with zero data loss (RPO=0) and high availability, as the stand-by replica can immediately take over if the entire availability zone fails.

Answer

Use a single database instance with automated snapshots to a different region

Answer

Deploy the database in a single availability zone with multiple EC2 instances

Answer

Use a read replica in a different region with asynchronous replication

Question 20

A company is using AWS and wants to minimize egress costs for data transferred out to the internet. Which strategy would be most effective?

Accepted Answer

Implement a CDN to cache content at edge locations. Using a CDN caches content at edge locations, reducing the amount of data transferred directly from the origin to users, thus lowering egress costs.

Answer

Use a VPN to encrypt traffic

Answer

Migrate to a different region with lower egress prices

Answer

Use a larger instance type to reduce data transfer