- A
The developer's local machine has a different operating system
Why wrong: PaaS abstracts the OS; the local OS difference is irrelevant to the cloud deployment.
- B
The PaaS provider updated the runtime environment, breaking compatibility
PaaS providers manage the runtime; an update can change versions or dependencies, causing the application to fail if not compatible.
- C
The application's database connection string is incorrect
Why wrong: A connection string error would typically cause a runtime error, not a failure to start, and the developer would likely have checked this.
- D
The cloud provider's physical server has a hardware fault
Why wrong: PaaS abstracts hardware; faults are handled by the provider and would affect multiple applications, not just one.
Quick Answer
The correct answer is that the PaaS provider updated the runtime environment, breaking compatibility with the application. This is the most likely cause because in a Platform as a Service model, the provider controls the underlying runtime, including language versions, libraries, and system dependencies. When the provider applies an update—such as upgrading the .NET runtime or swapping a database driver—it can silently introduce incompatibilities that prevent the application from starting, even though the developer’s own code remains unchanged. On the CompTIA A+ Core 1 220-1201 exam, this scenario tests your understanding of shared responsibility models: the provider manages the platform, so environmental changes are the prime suspect when code is error-free. A common trap is to blame the developer’s code or misconfigured scaling settings, but the key clue here is that the code checks out fine. Remember the memory tip: “PaaS update, app’s fate—check the runtime, not the code slate.”
220-1101 Cloud Computing Concepts Practice Question
This 220-1201 practice question tests your understanding of cloud computing concepts. The scenario asks you to isolate a root cause — eliminate options that address a different problem before choosing. 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 company uses a PaaS provider to deploy a custom web application. After an update, the application fails to start. The developer checks the code and finds no errors. What is the most likely cause of the failure?
Clue words in this question
Noticing these words before you look at the options changes how you read each choice.
Clue:
"most likely"Why it matters: Probability qualifier — the question wants the most probable cause or outcome, not a guaranteed one. Eliminate low-probability options.
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
The PaaS provider updated the runtime environment, breaking compatibility
In PaaS, the provider manages the runtime environment, including dependencies and configuration. An update may have changed the underlying platform (e.g., runtime version, library) that the application relies on, causing incompatibility. The developer's code is fine, so the issue is environmental.
Key principle: NAT direction and interface roles matter as much as the IP address mapping. Inside/outside designation controls which traffic is translated.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
The developer's local machine has a different operating system
Why it's wrong here
PaaS abstracts the OS; the local OS difference is irrelevant to the cloud deployment.
- ✓
The PaaS provider updated the runtime environment, breaking compatibility
Why this is correct
PaaS providers manage the runtime; an update can change versions or dependencies, causing the application to fail if not compatible.
Clue confirmation
The clue word "most likely" in the question point toward this answer.
Related concept
Static NAT maps one inside address to one outside address.
- ✗
The application's database connection string is incorrect
Why it's wrong here
A connection string error would typically cause a runtime error, not a failure to start, and the developer would likely have checked this.
- ✗
The cloud provider's physical server has a hardware fault
Why it's wrong here
PaaS abstracts hardware; faults are handled by the provider and would affect multiple applications, not just one.
Common exam traps
Common exam trap: NAT rules depend on direction and matching traffic
NAT is not only about the public address. The inside/outside interface roles and the ACL or rule that matches traffic are just as important.
Detailed technical explanation
How to think about this question
NAT questions usually test address translation, overload/PAT behaviour, static mappings and whether the right traffic is being translated. Read the interface direction and address terms carefully.
KKey Concepts to Remember
- Static NAT maps one inside address to one outside address.
- PAT allows many inside hosts to share one public address using ports.
- Inside local and inside global describe the private and translated addresses.
- NAT ACLs identify traffic for translation, not always security filtering.
TExam Day Tips
- Identify inside and outside interfaces first.
- Check whether the scenario needs static NAT, dynamic NAT or PAT.
- Do not confuse NAT matching ACLs with normal packet-filtering intent.
Key takeaway
NAT direction and interface roles matter as much as the IP address mapping. Inside/outside designation controls which traffic is translated.
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.
What to study next
Got this wrong? Here's your next step.
Review the four NAT address types (inside local, inside global, outside local, outside global), PAT port overload, and static vs dynamic NAT use cases. Then practise related 220-1201 NAT questions on configuration and troubleshooting.
- →
Cloud Computing Concepts — study guide chapter
Learn the concepts, then practise the questions
- →
Cloud Computing Concepts practice questions
Targeted practice on this topic area only
- →
All 220-1201 questions
1,020 questions across all exam domains
- →
CompTIA A+ Core 1 220-1201 study guide
Full concept coverage aligned to exam objectives
- →
220-1201 practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Related 220-1201 practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Mobile Device Hardware Servicing practice questions
Practise 220-1201 questions linked to Mobile Device Hardware Servicing.
Mobile Device Connection Methods practice questions
Practise 220-1201 questions linked to Mobile Device Connection Methods.
Mobile Device Accessories practice questions
Practise 220-1201 questions linked to Mobile Device Accessories.
Mobile Device Network Connectivity practice questions
Practise 220-1201 questions linked to Mobile Device Network Connectivity.
Mobile Device Application Support practice questions
Practise 220-1201 questions linked to Mobile Device Application Support.
Network Protocols practice questions
Practise 220-1201 questions linked to Network Protocols.
TCP & UDP Ports practice questions
Practise 220-1201 questions linked to TCP & UDP Ports.
Wireless Networking Technologies practice questions
Practise 220-1201 questions linked to Wireless Networking Technologies.
Network Services practice questions
Practise 220-1201 questions linked to Network Services.
Network Configuration Concepts practice questions
Practise 220-1201 questions linked to Network Configuration Concepts.
Common Networking Hardware practice questions
Practise 220-1201 questions linked to Common Networking Hardware.
IP Addressing practice questions
Practise 220-1201 questions linked to IP Addressing.
Practice this exam
Start a free 220-1201 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 220-1201 question test?
Cloud Computing Concepts — This question tests Cloud Computing Concepts — Static NAT maps one inside address to one outside address..
What is the correct answer to this question?
The correct answer is: The PaaS provider updated the runtime environment, breaking compatibility — In PaaS, the provider manages the runtime environment, including dependencies and configuration. An update may have changed the underlying platform (e.g., runtime version, library) that the application relies on, causing incompatibility. The developer's code is fine, so the issue is environmental.
What should I do if I get this 220-1201 question wrong?
Review the four NAT address types (inside local, inside global, outside local, outside global), PAT port overload, and static vs dynamic NAT use cases. Then practise related 220-1201 NAT questions on configuration and troubleshooting.
Are there clue words in this question I should notice?
Yes — watch for: "most likely". Probability qualifier — the question wants the most probable cause or outcome, not a guaranteed one. Eliminate low-probability options.
What is the key concept behind this question?
Static NAT maps one inside address to one outside address.
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: Jun 18, 2026
This 220-1201 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 220-1201 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.