200-901 Application Deployment and Security Practice Question
This 200-901 practice question tests your understanding of application deployment and security. 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 network administrator is deploying a custom container application on a Cisco Catalyst 9300 switch running IOS XE 16.12. The application is packaged as a .tar file and installed using 'app-hosting install app myapp flash:myapp.tar'. The administrator configures the app-hosting context as follows:
The administrator also creates a virtual port group 'vg0' and assigns it to the management interface. The application fails to start with the error: 'Application failed to start: guest interface not ready'. The administrator verifies that the .tar file is valid, the resources are sufficient, and the gateway is reachable. 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 the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
The guest-interface is not bound to the virtual port group.
The error 'guest interface not ready' indicates that the guest-interface (interface 0) is not properly bound to the virtual port group. After creating the virtual port group, the administrator must associate it with the app-vnic using the 'bind' command. Without this binding, the guest interface cannot obtain or use the IP configuration.
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.
✗
The application requires a DHCP server, but the configuration uses a static IP address.
Why it's wrong here
A static IP is valid and does not require DHCP; the error is about interface readiness, not IP assignment.
✓
The guest-interface is not bound to the virtual port group.
Why this is correct
The virtual port group must be explicitly bound to the app-vnic interface; otherwise, the interface remains 'not ready'.
Clue confirmation
The clue word "most likely" in the question point toward this answer.
The administrator already verified the file is valid, and the error points to the interface, not the image.
✗
The CPU allocation of 1000 units is insufficient for the application.
Why it's wrong here
The error message specifically mentions 'guest interface not ready', not resource exhaustion.
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 network engineer segments a warehouse floor into three subnets: 20 scanners, 5 printers, and 2 management hosts. Picking the wrong mask wastes addresses or leaves too few usable hosts. Exam questions test whether you can apply CIDR notation, calculate block size, and identify the correct usable-host range for a given prefix.
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 200-901 subnetting questions on CIDR, address ranges, and subnet selection.
Application Deployment and Security — This question tests Application Deployment and Security — CIDR notation defines the prefix length..
What is the correct answer to this question?
The correct answer is: The guest-interface is not bound to the virtual port group. — The error 'guest interface not ready' indicates that the guest-interface (interface 0) is not properly bound to the virtual port group. After creating the virtual port group, the administrator must associate it with the app-vnic using the 'bind' command. Without this binding, the guest interface cannot obtain or use the IP configuration.
What should I do if I get this 200-901 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 200-901 subnetting questions on CIDR, address ranges, and subnet selection.
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?
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 →
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.
This 200-901 practice question is part of Courseiva's free Cisco 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 200-901 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.