- A
The source zone is incorrectly assigned.
Why wrong: Incorrect zone would likely cause a different rule match, not an unexpected block.
- B
The application override is misconfigured.
Why wrong: Application override affects application identification, not blocking.
- C
The profile settings for the security policy are blocking the traffic.
Why wrong: Profile settings like antivirus or vulnerability protection can block, but the question states the traffic is allowed in the security policy, meaning profiles are applied after the rule matches.
- D
The IP address is on a block list in the External Dynamic List (EDL).
An EDL block list overrides security policy rules.
Question 204 of 516
EDL Block List Overrides Security Policy
This PCNSE practice question tests your understanding of manage, monitor and operate. 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 notices that traffic from a specific IP address is being blocked unexpectedly. The traffic is allowed in the security policy. What is the most likely cause?
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 IP address is on a block list in the External Dynamic List (EDL).
The most likely cause is that the IP address is on a block list in an External Dynamic List (EDL). Even if a security policy explicitly allows traffic from that IP, a block list configured in an EDL overrides the policy because the firewall evaluates threat prevention and URL filtering profiles, including EDL-based block lists, before or in parallel with security policy rules. This is a common troubleshooting scenario where traffic is allowed by policy but still blocked due to a higher-priority security profile action.
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 source zone is incorrectly assigned.
Why it's wrong here
Incorrect zone would likely cause a different rule match, not an unexpected block.
- ✗
The application override is misconfigured.
Why it's wrong here
Application override affects application identification, not blocking.
- ✗
The profile settings for the security policy are blocking the traffic.
Why it's wrong here
Profile settings like antivirus or vulnerability protection can block, but the question states the traffic is allowed in the security policy, meaning profiles are applied after the rule matches.
- ✓
The IP address is on a block list in the External Dynamic List (EDL).
Why this is correct
An EDL block list overrides security policy rules.
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.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates often assume a security policy 'allow' rule is absolute, but they forget that security profiles (including EDL-based block lists) can override the policy action, leading them to incorrectly choose profile settings (Option C) instead of recognizing the specific IP-based blocking mechanism of an EDL.
Detailed technical explanation
How to think about this question
External Dynamic Lists (EDLs) in Palo Alto Networks firewalls are lists of IP addresses, URLs, or domains that can be updated dynamically from external sources. When an EDL is configured in a Security Profile (e.g., Anti-Spyware or URL Filtering) and set to 'block', the firewall will drop traffic matching entries in that list regardless of the security policy rule that permits the traffic. This is because the firewall processes security profiles after the initial policy match, and a block action in a profile overrides the permit action of the policy. In a real-world scenario, an administrator might add a known malicious IP to an EDL for immediate blocking, but forget to remove it after the threat is mitigated, causing legitimate traffic to be blocked.
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.
Visual reference
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.
- →
Manage, Monitor and Operate — study guide chapter
Learn the concepts, then practise the questions
- →
Manage, Monitor and Operate practice questions
Targeted practice on this topic area only
- →
All PCNSE questions
516 questions across all exam domains
- →
Palo Alto Networks Certified Network Security Engineer PCNSE study guide
Full concept coverage aligned to exam objectives
- →
PCNSE practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Related PCNSE practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Manage, Monitor and Operate practice questions
Practise PCNSE questions linked to Manage, Monitor and Operate.
Securing Traffic and App-ID practice questions
Practise PCNSE questions linked to Securing Traffic and App-ID.
Securing Users and Applications with Authentication practice questions
Practise PCNSE questions linked to Securing Users and Applications with Authentication.
Decryption and SSL Inspection practice questions
Practise PCNSE questions linked to Decryption and SSL Inspection.
Managing Troubleshooting and High Availability practice questions
Practise PCNSE questions linked to Managing Troubleshooting and High Availability.
Deploy and Configure Firewalls practice questions
Practise PCNSE questions linked to Deploy and Configure Firewalls.
Core Concepts and Architecture practice questions
Practise PCNSE questions linked to Core Concepts and Architecture.
Secure Access and VPN practice questions
Practise PCNSE questions linked to Secure Access and VPN.
Troubleshoot practice questions
Practise PCNSE questions linked to Troubleshoot.
PCNSE fundamentals practice questions
Practise PCNSE questions linked to PCNSE fundamentals.
PCNSE scenario practice questions
Practise PCNSE questions linked to PCNSE scenario.
PCNSE troubleshooting practice questions
Practise PCNSE questions linked to PCNSE troubleshooting.
Practice this exam
Start a free PCNSE 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 PCNSE question test?
Manage, Monitor and Operate — This question tests Manage, Monitor and Operate — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: The IP address is on a block list in the External Dynamic List (EDL). — The most likely cause is that the IP address is on a block list in an External Dynamic List (EDL). Even if a security policy explicitly allows traffic from that IP, a block list configured in an EDL overrides the policy because the firewall evaluates threat prevention and URL filtering profiles, including EDL-based block lists, before or in parallel with security policy rules. This is a common troubleshooting scenario where traffic is allowed by policy but still blocked due to a higher-priority security profile action.
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 →
Keep practising
More PCNSE practice questions
- Arrange the steps to enable and configure GlobalProtect on a Palo Alto Networks firewall.
- Order the steps to upgrade the PAN-OS software on a standalone firewall.
- An administrator notices that traffic from zone A to zone B is being dropped silently. Security rules are in place. Trou…
- Which component of the PAN-OS architecture is responsible for processing security policies and performing packet inspect…
- A company has configured a security policy that allows HTTP traffic from the internal network 10.0.0.0/8 to the internet…
- An organization wants to map user identity from Active Directory for traffic coming from internal LAN users without inst…
Last reviewed: Jul 4, 2026
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.