This PCNSA practice question tests your understanding of decryption and monitoring. This is a configuration task: choose the command set that satisfies every stated requirement. Small differences — like 'secret' vs 'password' or 'transport input ssh' vs 'all' — change whether the answer is correct. 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 wants to decrypt all SSL traffic from internal users to external websites. They have deployed a Palo Alto Networks firewall in forward proxy mode and installed a trusted root CA certificate on all endpoints. Users, however, are complaining about certificate errors when accessing HTTPS sites. Which configuration step is most likely missing?
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 firewall's decryption certificate is not signed by the installed root CA.
Option C is correct because in forward proxy decryption, the firewall generates a decryption certificate that must be signed by the trusted root CA installed on the endpoints. If the decryption certificate is self-signed or signed by a different CA, the browser will not trust it, causing certificate errors. The root CA certificate must be installed on all endpoints to establish a chain of trust for the firewall-generated certificates.
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 decryption profile is set to block sessions with untrusted certificates.
Why it's wrong here
Blocking untrusted certificates would result in blocked sessions, not just certificate errors.
✗
The firewall is performing inbound inspection instead of forward proxy.
Why it's wrong here
Inbound inspection is for traffic destined to servers, not outbound client traffic.
✓
The firewall's decryption certificate is not signed by the installed root CA.
Why this is correct
The firewall's decryption certificate must be signed by the root CA installed on endpoints; otherwise, errors occur.
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.
✗
No decryption profile is attached to the decryption rule.
Why it's wrong here
Without a profile, the firewall uses default settings which still decrypt traffic.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates often confuse the need for a decryption profile (Option D) with the fundamental requirement of a trusted root CA certificate, or they mistakenly think blocking untrusted certificates (Option A) is the cause of errors rather than a consequence of missing trust.
Detailed technical explanation
How to think about this question
In forward proxy decryption, the firewall intercepts the ClientHello and generates a certificate on the fly for the requested domain, signed by the firewall's CA certificate. The browser validates this certificate against its trusted root store; if the firewall's CA is not in that store, the browser displays a certificate error (e.g., NET::ERR_CERT_AUTHORITY_INVALID). This is distinct from SSL forward proxy where the firewall re-encrypts traffic using its own certificate, requiring the root CA to be trusted by the client.
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 PCNSA 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.
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.
Decryption and Monitoring — This question tests Decryption and Monitoring — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: The firewall's decryption certificate is not signed by the installed root CA. — Option C is correct because in forward proxy decryption, the firewall generates a decryption certificate that must be signed by the trusted root CA installed on the endpoints. If the decryption certificate is self-signed or signed by a different CA, the browser will not trust it, causing certificate errors. The root CA certificate must be installed on all endpoints to establish a chain of trust for the firewall-generated certificates.
What should I do if I get this PCNSA 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 PCNSA 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 PCNSA 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.