- A
Public subnet for web and application servers, private subnet for database servers
Why wrong: Application servers do not need to be in a public subnet.
- B
Single public subnet with all servers placed in it, using security groups to restrict traffic
Why wrong: Placing all servers in a public subnet exposes them unnecessarily to the internet.
- C
Public subnet for web servers, private subnet for application servers, and a separate private subnet for database servers, with proper security group rules
This design isolates each tier and limits exposure, following best practices.
- D
Use a single private subnet and a NAT gateway for internet access
Why wrong: This would not allow web servers to be accessible from the internet unless a load balancer is used in a public subnet.
CV0-004 Cloud Architecture and Design Practice Question
This CV0-004 practice question tests your understanding of cloud architecture and design. Match the stated requirement to the specific cloud service, access model, or configuration option — many options are valid in isolation but not for this scenario. 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.
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 should only be accessible from the web servers, and the database servers should only be accessible from the application servers. What is the most secure VPC design?
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
Public subnet for web servers, private subnet for application servers, and a separate private subnet for database servers, with proper security group rules
A three-tier VPC design uses public subnets for web servers (with an internet gateway) and private subnets for application and database servers, with security group rules restricting traffic between tiers.
Key principle: Count usable hosts — not total addresses — and remember that the network and broadcast addresses are not available to hosts in standard IPv4 subnets.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Public subnet for web and application servers, private subnet for database servers
Why it's wrong here
Application servers do not need to be in a public subnet.
- ✗
Single public subnet with all servers placed in it, using security groups to restrict traffic
Why it's wrong here
Placing all servers in a public subnet exposes them unnecessarily to the internet.
- ✓
Public subnet for web servers, private subnet for application servers, and a separate private subnet for database servers, with proper security group rules
Why this is correct
This design isolates each tier and limits exposure, following best practices.
Related concept
CIDR notation defines the prefix length.
- ✗
Use a single private subnet and a NAT gateway for internet access
Why it's wrong here
This would not allow web servers to be accessible from the internet unless a load balancer is used in a public subnet.
Common exam traps
Common exam trap: usable hosts are not the same as total addresses
Subnetting questions often tempt you into counting all addresses. In normal IPv4 subnets, the network and broadcast addresses are not usable host addresses.
Detailed technical explanation
How to think about this question
Subnetting questions test whether you can identify the network, broadcast address, usable range, mask and correct subnet. Slow down enough to calculate the block size correctly.
KKey Concepts to Remember
- CIDR notation defines the prefix length.
- Block size helps identify subnet boundaries.
- Network and broadcast addresses are not usable hosts in normal IPv4 subnets.
- The required host count determines the smallest suitable subnet.
TExam Day Tips
- Write the block size before choosing the subnet.
- Check whether the question asks for hosts, subnets or a specific address range.
- Do not confuse /24, /25, /26 and /27 host counts.
Key takeaway
Count usable hosts — not total addresses — and remember that the network and broadcast addresses are not available to hosts in standard IPv4 subnets.
Real-world example
How this comes up in practice
A small business has 20 workstations on the 192.168.1.0/24 network and one public IP from its ISP. The router uses PAT (NAT overload) so all 20 devices share one public address using different source ports. NAT questions test whether you understand the four address terms and which direction each translation applies.
Visual reference
What to study next
Got this wrong? Here's your next step.
Review block sizes, usable host formulas (2^n − 2), and how to find network and broadcast addresses for /24 through /30. Then practise related CV0-004 subnetting questions on CIDR, address ranges, and subnet selection.
- →
Cloud Architecture and Design — study guide chapter
Learn the concepts, then practise the questions
- →
Cloud Architecture and Design practice questions
Targeted practice on this topic area only
- →
All CV0-004 questions
997 questions across all exam domains
- →
CompTIA Cloud+ CV0-004 study guide
Full concept coverage aligned to exam objectives
- →
CV0-004 practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Related CV0-004 practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Cloud Architecture and Design practice questions
Practise CV0-004 questions linked to Cloud Architecture and Design.
Deployment practice questions
Practise CV0-004 questions linked to Deployment.
Security practice questions
Practise CV0-004 questions linked to Security.
Operations and Support practice questions
Practise CV0-004 questions linked to Operations and Support.
Troubleshooting practice questions
Practise CV0-004 questions linked to Troubleshooting.
CV0-004 fundamentals practice questions
Practise CV0-004 questions linked to CV0-004 fundamentals.
CV0-004 scenario practice questions
Practise CV0-004 questions linked to CV0-004 scenario.
CV0-004 troubleshooting practice questions
Practise CV0-004 questions linked to CV0-004 troubleshooting.
Practice this exam
Start a free CV0-004 practice session
Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.
FAQ
Questions learners often ask
What does this CV0-004 question test?
Cloud Architecture and Design — This question tests Cloud Architecture and Design — CIDR notation defines the prefix length..
What is the correct answer to this question?
The correct answer is: Public subnet for web servers, private subnet for application servers, and a separate private subnet for database servers, with proper security group rules — A three-tier VPC design uses public subnets for web servers (with an internet gateway) and private subnets for application and database servers, with security group rules restricting traffic between tiers.
What should I do if I get this CV0-004 question wrong?
Review block sizes, usable host formulas (2^n − 2), and how to find network and broadcast addresses for /24 through /30. Then practise related CV0-004 subnetting questions on CIDR, address ranges, and subnet selection.
What is the key concept behind this question?
CIDR notation defines the prefix length.
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 →
Last reviewed: Jul 4, 2026
This CV0-004 practice question is part of Courseiva's free CompTIA 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 CV0-004 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.