PCNSE Securing Traffic and App-ID Practice Question
This PCNSE practice question tests your understanding of securing traffic and app-id. Read the scenario carefully and evaluate each option against the stated constraints before committing to an answer. 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.
Exhibit
Refer to the exhibit.
> show app-app-id counter
Application Packets Flags
web-browsing 1000
ssl 500
my-custom-app 0
> show app-override rule
Name: Override-SSH
Source: 10.0.0.0/24
Destination: 10.1.0.0/24
Application: my-custom-app
An engineer checks the application counter and sees that my-custom-app has zero packets, but they expected traffic from 10.0.0.0/24 to 10.1.0.0/24 to be identified as my-custom-app. What is the most likely reason?
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.
Exhibit
Refer to the exhibit.
> show app-app-id counter
Application Packets Flags
web-browsing 1000
ssl 500
my-custom-app 0
> show app-override rule
Name: Override-SSH
Source: 10.0.0.0/24
Destination: 10.1.0.0/24
Application: my-custom-app
A
The traffic is being identified as ssl instead.
Why wrong: Counter shows ssl packets, but this could be unrelated traffic. The issue is the missing port in the override rule.
B
The application override rule does not have the correct port.
Correct: Without a port, the override rule does not trigger, and traffic is identified normally.
C
The security policy does not allow the traffic.
Why wrong: Security policy is about allowing or denying, but identification happens before that. Even if denied, it would still be counted in the application counter.
D
The custom application my-custom-app is not committed.
Why wrong: If not committed, the application would still appear in the configuration, but the counter shows zero. The commit status is not the issue here.
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
The application override rule does not have the correct port.
Option B is correct because an application override rule explicitly maps traffic to a custom application based on IP address, protocol, and port. If the port in the override rule does not match the actual destination port used by the traffic (e.g., TCP/8080 instead of TCP/80), the firewall will not classify the traffic as my-custom-app, resulting in zero packets for that application counter. The traffic may still pass but will be identified by App-ID as another application or remain unidentified.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
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 traffic is being identified as ssl instead.
Why it's wrong here
Counter shows ssl packets, but this could be unrelated traffic. The issue is the missing port in the override rule.
✓
The application override rule does not have the correct port.
Why this is correct
Correct: Without a port, the override rule does not trigger, and traffic is identified normally.
Clue confirmation
The clue word "most likely" in the question point toward this answer.
Related concept
Read the scenario before looking for a memorised answer.
✗
The security policy does not allow the traffic.
Why it's wrong here
Security policy is about allowing or denying, but identification happens before that. Even if denied, it would still be counted in the application counter.
✗
The custom application my-custom-app is not committed.
Why it's wrong here
If not committed, the application would still appear in the configuration, but the counter shows zero. The commit status is not the issue here.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates often assume the issue is with the security policy blocking traffic (Option C) or with the application not being committed (Option D), but the zero-packet counter specifically for the custom app points to a matching failure in the override rule, not a policy or commit problem.
Trap categories for this question
Command / output trap
Counter shows ssl packets, but this could be unrelated traffic. The issue is the missing port in the override rule.
Detailed technical explanation
How to think about this question
Application override rules in PAN-OS use a 5-tuple match (source/destination IP, protocol, source/destination port) to bypass App-ID and force classification to a specific application. If the port in the override rule is incorrect (e.g., TCP/443 instead of TCP/80), the traffic will not match the override and will fall through to standard App-ID, which may identify it as web-browsing or ssl instead. A common real-world scenario is when an engineer configures an override for a custom web application but forgets to specify the correct non-standard port, causing the traffic to be misidentified.
KKey Concepts to Remember
Read the scenario before looking for a memorised answer.
Find the constraint that changes the correct option.
Eliminate answers that are true in general but not in this case.
TExam Day Tips
→Watch for words such as best, first, most likely and least administrative effort.
→Review why wrong options are wrong, not only why the correct option is correct.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
How this comes up in practice
A practitioner preparing for the PCNSE exam encounters this exact type of scenario on the job. The correct answer here is not the most general option — it is the best answer for the specific constraint described. Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option. Real exam questions reward reading the full scenario before eliminating options, because the constraint defines which answer fits.
Quick reference
IPv4 Address Class Summary
Class
First Octet Range
Default Mask
Networks
Hosts per Network
A
1–126
/8 (255.0.0.0)
126
16,777,214
B
128–191
/16 (255.255.0.0)
16,384
65,534
C
192–223
/24 (255.255.255.0)
2,097,152
254
D
224–239
N/A
Multicast groups
—
E
240–255
N/A
Reserved / experimental
—
127.x.x.x is reserved for loopback. Modern networks use CIDR (classless) rather than classful addressing.
What to study next
Got this wrong? Here's your next step.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Securing Traffic and App-ID — This question tests Securing Traffic and App-ID — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: The application override rule does not have the correct port. — Option B is correct because an application override rule explicitly maps traffic to a custom application based on IP address, protocol, and port. If the port in the override rule does not match the actual destination port used by the traffic (e.g., TCP/8080 instead of TCP/80), the firewall will not classify the traffic as my-custom-app, resulting in zero packets for that application counter. The traffic may still pass but will be identified by App-ID as another application or remain unidentified.
What should I do if I get this PCNSE question wrong?
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
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?
Read the scenario before looking for a memorised answer.
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 PCNSE practice question is part of Courseiva's free Palo Alto Networks 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 PCNSE 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.