- A
Upgrade both firewalls to the same software version and then re-initialize HA
Why wrong: Software version is assumed same; re-initializing may help but the root cause is not software version.
- B
Change the HA mode to active/active and enable asymmetric routing
Why wrong: Does not resolve the suspended state.
- C
Reboot both firewalls after verifying the HA configuration and that the links are operationally up
Rebooting recovers from suspended state; links are up now.
- D
Configure a dedicated management interface for HA1 communication and ensure HA2 is on a different subnet
Why wrong: HA1 and HA2 must be on the same subnet; this suggestion is incorrect and does not fix suspension.
Question 85 of 516
Recovering HA Pair from Suspended State After HA Link Loss
This PCNSE practice question tests your understanding of managing troubleshooting and high availability. 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 medium-sized enterprise has two Palo Alto Networks PA-5250 firewalls configured in an active/passive HA pair with session synchronization and configuration synchronization enabled. The HA1 link is a direct copper cable, and the HA2 link is also a direct copper cable. The firewalls are connected to two upstream routers (R1 and R2) and two downstream switches (S1 and S2). The network uses OSPF for dynamic routing. The active firewall (FW-A) is connected to R1 and S1, while the passive firewall (FW-P) is connected to R2 and S2. The OSPF cost is set symmetrically on both sides. During a maintenance window, the network team shuts down the HA1 and HA2 links on both firewalls to test failover behavior. After the links are brought back up, the firewalls are in a state of 'non-functional' and 'suspended'. The team suspects the HA configuration is broken. What is the most likely cause and the best course of action to restore HA?
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
✓
Reboot both firewalls after verifying the HA configuration and that the links are operationally up
When both HA1 and HA2 links are simultaneously shut down on both firewalls, the active/passive pair loses all communication and session synchronization. Upon restoration, the firewalls enter a 'non-functional' and 'suspended' state because the HA control plane cannot re-establish a quorum or verify the peer's state without a full reset of the HA state machine. Rebooting both firewalls after verifying the HA configuration and that the links are operationally up forces a clean initialization of the HA process, clearing the suspended state and allowing the pair to renegotiate roles correctly.
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.
- ✗
Upgrade both firewalls to the same software version and then re-initialize HA
Why it's wrong here
Software version is assumed same; re-initializing may help but the root cause is not software version.
- ✗
Change the HA mode to active/active and enable asymmetric routing
Why it's wrong here
Does not resolve the suspended state.
- ✓
Reboot both firewalls after verifying the HA configuration and that the links are operationally up
Why this is correct
Rebooting recovers from suspended state; links are up now.
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.
- ✗
Configure a dedicated management interface for HA1 communication and ensure HA2 is on a different subnet
Why it's wrong here
HA1 and HA2 must be on the same subnet; this suggestion is incorrect and does not fix suspension.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates assume re-establishing the HA links alone will automatically restore the HA pair, but PAN-OS requires a full reboot of both firewalls to clear the suspended state after a simultaneous HA link failure, as the state machine does not have a built-in recovery mechanism for this scenario.
Detailed technical explanation
How to think about this question
In PAN-OS, the HA state machine uses a 'hold timer' (default 3 seconds) to detect peer loss; when both HA1 and HA2 go down simultaneously, the passive firewall cannot confirm the active's status, leading to a 'suspended' state to prevent split-brain scenarios. The 'show high-availability state' command would reveal the suspended status, and the only way to clear it without manual intervention is to reboot both units, as the HA process does not automatically recover from a simultaneous link failure due to the lack of a tie-breaker mechanism. This behavior is documented in the PAN-OS High Availability Administrator's Guide, which recommends rebooting both firewalls after such a test.
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 network engineer at a university connects two campus buildings via a fibre link. Both routers run OSPF, but no adjacency forms — even though both routers can ping each other. The engineer finds one router is in area 0 and the other in area 1. OSPF adjacency requires matching area numbers, hello/dead timers, and network type. IP reachability alone is not enough.
Visual reference
Quick reference
Routing Protocol Comparison
| Protocol | Metric | Max Hops | Algorithm | Type |
|---|---|---|---|---|
| RIP v2 | Hop count | 15 | Bellman-Ford | Distance vector |
| OSPF | Cost (bandwidth) | Unlimited | Dijkstra (SPF) | Link state |
| EIGRP | Composite metric | Unlimited | DUAL | Hybrid |
| IS-IS | Cost | Unlimited | Dijkstra | Link state |
| BGP | Policy / attributes | Unlimited | Path vector | Path vector |
RIP's 15-hop limit makes it unsuitable for large networks. OSPF and EIGRP dominate modern enterprise deployments.
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.
- →
Managing Troubleshooting and High Availability — study guide chapter
Learn the concepts, then practise the questions
- →
Managing Troubleshooting and High Availability 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?
Managing Troubleshooting and High Availability — This question tests Managing Troubleshooting and High Availability — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Reboot both firewalls after verifying the HA configuration and that the links are operationally up — When both HA1 and HA2 links are simultaneously shut down on both firewalls, the active/passive pair loses all communication and session synchronization. Upon restoration, the firewalls enter a 'non-functional' and 'suspended' state because the HA control plane cannot re-establish a quorum or verify the peer's state without a full reset of the HA state machine. Rebooting both firewalls after verifying the HA configuration and that the links are operationally up forces a clean initialization of the HA process, clearing the suspended state and allowing the pair to renegotiate roles correctly.
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.