B. Disable config sync.

Explanation:

Why Disable Config Sync?
1.HA Pair Behavior:
In an active/passive HA pair, the active firewall handles traffic while the passive firewall syncs configuration and sessions.
When you import the HA pair into Panorama, Panorama pushes configurations to both firewalls.

2.Risk of Disruption:
If the configuration push occurs during sync, it may cause temporary inconsistencies or restart services (e.g., routing daemons).
Disabling config sync temporarily prevents the passive firewall from receiving changes, avoiding disruptions.

3.Safe Import Steps:
Disable config sync on the HA pair:
> set high-availability state-synchronization enabled no Import the configuration into Panorama.
Re-enable config sync after import.

Why Not Other Options?
A.Shutting down the passive link breaks HA integrity (may trigger failover).
C.Disabling HA2 breaks session sync (causes session loss on failover).
D.Disabling HA entirely breaks redundancy and may disrupt traffic.

Reference:
Panorama HA Integration Guide:
"Temporarily disable state synchronization before importing HA configurations to avoid traffic impact."

B. It matches to the New App-IDs in the most recently installed content releases.

Explanation:
The New App-ID characteristic in Palo Alto Networks firewalls is designed to help administrators monitor newly introduced applications that may require updates to Security policy. When you create a report under Monitor > Reports > Application Reports > New Applications, the firewall identifies “new” applications based on the most recently installed content release—not based on time duration or system reboot.
This means the report will only include App-IDs that were added in the latest content update installed on the firewall, regardless of when that update was downloaded or how long ago the system was rebooted.
This behavior is confirmed in Palo Alto’s official documentation:
“The New App-ID characteristic always matches to only the new App-IDs in the most recently installed content releases.”

❌ Why the other options are incorrect
A. Last 90 days:
Time-based filtering is not used. The firewall doesn’t track App-ID age by days.
C. Last 30 days:
Same issue—App-ID identification is based on content version, not time.
D. Since last reboot:
Rebooting the firewall has no impact on App-ID classification. The report is tied to content updates, not system uptime.

🔗 Reference:
You can find this behavior detailed in Palo Alto’s Monitor New App-IDs documentation

A. Add SSL and web-browsing applications to the same rule.

Explanation:
In PAN-OS, every application has a set of dependencies and implicit uses. For GlobalProtect, the application:

Depends on SSL
→ must be explicitly allowed in the same rule
Implicitly uses web-browsing
→ does not require explicit allowance, but including it avoids misclassification delays during App-ID identification

To ensure full functionality and proper App-ID resolution, both SSL and web-browsing should be added to the same rule. This guarantees that the firewall can correctly identify and allow GlobalProtect traffic without delay or drop.

❌ Why the Other Options Are Incorrect:
B. Add web-browsing application to the same rule
→ Misses the required SSL dependency. GlobalProtect won’t work without SSL explicitly allowed.
C. Add SSL application to the same rule
→ Misses the implicit web-browsing usage. While technically functional, it may delay App-ID resolution.
D. SSL and web-browsing must both be explicitly allowed
→ Misleading. Only SSL is a dependency; web-browsing is implicitly used and doesn’t require explicit allowance unless you want to optimize App-ID recognition.

Reference:
Palo Alto Networks – What is Application Dependency
PCNSE Dependency Resolution Guide

B. Schedules
D. Revert content
E. Install

Explanation:
Panorama, the centralized management platform for Palo Alto Networks firewalls, provides several options for deploying dynamic updates (e.g., Applications and Threats, Antivirus, WildFire signatures) to managed devices. These updates are critical for maintaining up-to-date threat prevention capabilities. The question focuses on the specific actions Panorama offers for managing these updates. Schedules, Revert content, and Install are three distinct options available in Panorama for deploying and managing dynamic updates, ensuring efficient and controlled distribution to firewalls. Below is a concise explanation of why these options are correct and why the others are incorrect, tailored for the PCNSE exam.

B. Schedules:
Panorama allows administrators to configure schedules for dynamic updates under Panorama > Dynamic Updates. This feature automates the process of checking for, downloading, and installing updates (e.g., Applications and Threats, Antivirus) on managed firewalls at specified intervals (e.g., daily, weekly). Schedules ensure that devices stay current with the latest threat intelligence without manual intervention, with options to set thresholds (e.g., only install updates newer than a specific version).
Example: Configure a schedule to check for Antivirus updates every 4 hours and install them automatically.

D. Revert content:
The Revert content option in Panorama (under Panorama > Dynamic Updates) allows administrators to roll back to a previous version of dynamic update content (e.g., Applications and Threats database) if a new update causes issues. This is useful for troubleshooting or addressing compatibility problems with managed firewalls, ensuring stability by reverting to a known good state.
Example: Revert to an earlier Applications and Threats version if a new update disrupts application identification.

E. Install:
The Install option enables administrators to manually push dynamic updates to managed firewalls from Panorama (via Panorama > Dynamic Updates > Install). After downloading updates, Panorama can install them immediately or stage them for deployment to specific Device Groups or firewalls, providing control over when updates are applied. Example: Manually install a new WildFire signature update to all firewalls in a Device Group.

Why Other Options Are Incorrect
A. Check dependencies:
While Panorama performs dependency checks during PAN-OS upgrades or content installations to ensure compatibility (e.g., verifying the minimum PAN-OS version for an update), Check dependencies is not a standalone option for deploying dynamic updates. It is an internal process, not a configurable action in the Dynamic Updates interface.

C. Verify:
Panorama does not offer a specific Verify option for dynamic updates. While it verifies the integrity of downloaded updates (e.g., via digital signatures), this is an automatic process, not a user-selectable action in the Dynamic Updates workflow. Verification is not listed as a deployment option.

Technical Details
Schedules Configuration:
Navigate to Panorama > Dynamic Updates, click Schedules, and configure update type (e.g., Applications and Threats), frequency, and action (download only or download and install). CLI: set deviceconfig system update-schedule recurring .

Revert Content:
In Panorama > Dynamic Updates, select an update, click Revert, and choose a previous version to restore.
CLI: request content revert version .

Install:
In Panorama > Dynamic Updates, select an update and click Install, choosing target Device Groups or firewalls.
CLI: request content upgrade install version .
Monitoring: Use Panorama > Monitor > Dynamic Updates Logs to track update deployment status.

PCNSE Relevance
The PCNSE exam tests your ability to manage dynamic updates via Panorama, including scheduling, installing, and reverting content to ensure firewalls remain protected against new threats. Understanding these options is critical for centralized management scenarios.

References:
Palo Alto Networks Documentation (PAN-OS Admin Guide): Details dynamic update management in Panorama, including scheduling and installing updates.
Palo Alto Networks Knowledge Base (Article ID: 000032789): Explains reverting content and managing update deployments in Panorama.

C. Ping interval of 200 ms and ping count of 10 failed pings

Explanation:
In Palo Alto Networks High Availability (HA) configuration, path monitoring is used to detect link or path failures by sending periodic pings to a monitored IP address. If the pings fail consistently, a failover is triggered.

The default values for path monitoring are:
Ping Interval: 200 milliseconds
Ping Count: 10 consecutive failed pings
This means the firewall will wait for 10 failed pings, each spaced 200 ms apart, before initiating a failover.
📚 Reference:
Palo Alto Networks – Configure HA Path Monitoring

❌ Why Other Options Are Wrong:
A. Incorrect ping count (only 3)
B. & D. Incorrect ping interval (5000 ms is not default)

C. The client received a CA certificate that has expired or is not valid.

Explanation:

Key Evidence from the Log:
1.Certificate Details:
Issuer: Entrust Certification Authority - L1M
Root CA: Entrust Root Certification Authority - G2 (trusted).
Expiry Date: 2022/04/01 15:38:03 (log timestamp: 2022/03/03).
The certificate was still valid at the time of the session, but the log shows a deny action.
2.Error Context:
Action: deny (blocked by rule Social-Media-Override).
Application: ssl (TLS/SSL handshake failure).
3.Possible Causes:
Intermediate CA (L1M) expired/revoked: Though the root CA is trusted, the chain might be broken.
Certificate validation failure: The firewall or client rejected the intermediate CA.

Why Not Other Options?
ANo mention of fingerprint mismatch in the log.
BThe log confirms the expected CA (Entrust).
DEntrust is trusted (Root CA is listed as trusted).

Root Cause Analysis:
The intermediate CA (L1M) might have been:
Revoked (not shown in the log but plausible).
Expired post-log (though the log shows it was valid at the time).
The firewall’s decryption profile likely enforced strict validation, rejecting the chain.

Reference:
Palo Alto Decryption Troubleshooting:
"Denied SSL sessions often result from invalid intermediate CA certificates or revocation checks."

A. A secondary DNS server in the DNS proxy is optional, and configuration commit to the firewall will succeed with only one DNS server.

Explanation:
When configuring DNS Proxy for Explicit Proxy (web proxy), the firewall allows you to specify primary and secondary DNS servers. However, the configuration validation only requires a primary DNS server to be defined. The commit operation will succeed with just one DNS server configured.

Why the other options are incorrect:
B. A maximum of two FQDNs can be mapped to an IP address in the static entries for DNS proxy:
This is false. There is no hard-coded limit on the number of FQDNs that can be mapped to a single IP address in the static entries of the DNS proxy configuration.
C. DNS timeout for web proxy can be configured manually, and it should be set to the highest value possible:
This is incorrect and not a best practice. The DNS timeout value should be set appropriately based on network conditions. Setting it to an excessively high value could cause unnecessary delays in DNS resolution and degrade user experience.
D. Adjust the UDP queries for the DNS proxy to allow both DNS servers to be tried within 20 seconds:
This is misleading. The default behavior of the DNS proxy is to query the primary server first, and if no response is received within the configured timeout (default is 2 seconds), it will try the secondary server. The total time for both attempts is not fixed at 20 seconds; it depends on the configured timeout and number of retries.

Reference:
Palo Alto Networks Administrator Guide:
The "DNS Proxy" section confirms that while multiple DNS servers can be configured for redundancy, only one is required for a valid configuration.
PCNSE Exam Blueprint (Domain 2:
Deployment and Configuration): Understanding DNS proxy configuration for explicit proxy deployments is a key objective within the blueprint.