PCNSE Palo Alto Networks Certified Security Engineer (PCNSE) PAN-OS 10.2 Questions and Answers

The compare option for a specific rule in the New App Viewer under Policy Optimizer allows an administrator to compare the applications configured in the rule with the applications seen from traffic matching the same rule. This helps the administrator to identify any new applications that are not explicitly defined in the rule, but are implicitly allowed by the firewall based on the dependencies of the configured applications. The compare option also shows the usage statistics and risk levels of the applications, and provides suggestions for optimizing the rule by adding, removing, or replacing applications12. References: New App Viewer (Policy Optimizer), PCNSE Study Guide (page 47)

Why use Security Policy Optimizer and what are the benefits?

https://docs.paloaltonetworks.com/pan-os/10-1/pan-os-web-interface-help/network/network-network-profiles/network-network-profiles-monitor.html

https://docs.paloaltonetworks.com/pan-os/10-2/pan-os-admin/user-id/map-ip-addresses-to-users/configure-user-id-to-monitor-syslog-senders-for-user-mapping#iddb1a7744-17c6-4900-a2cb-5f3511fef60f

When the peer device will act as the initiator and none of the peer addresses are known, the administrator can enable Passive Mode to establish the VPN connection. Passive Mode tells the firewall to wait for the peer device to initiate the VPN connection. The other options are incorrect. Option A, setting up certificate authentication, would require the administrator to know the peer device's certificate. Option C, using the Dynamic IP address type, would require the administrator to know the peer device's dynamic IP address. Option D, configuring the peer address as an FQDN, would require the administrator to know the peer device's fully qualified domain name.

https://knowledgebase.paloaltonetworks.com/KCSArticleDetail?id=kA10g000000ClIGCA0

https://docs.paloaltonetworks.com/globalprotect/9-1/globalprotect-admin/globalprotect-gateways/split-tunnel-traffic-on-globalprotect-gateways/configure-a-split-tunnel-based-on-the-domain-and-application

https://knowledgebase.paloaltonetworks.com/kCSArticleDetail?id=kA10g000000PMiD

https://docs.paloaltonetworks.com/globalprotect/9-1/globalprotect-admin/globalprotect-gateways/split-tunnel-traffic-on-globalprotect-gateways/configure-a-split-tunnel-based-on-the-domain-and-application

https://docs.paloaltonetworks.com/pan-os/10-2/pan-os-admin/vpns/set-up-site-to-site-vpn/interpret-vpn-error-messages

The VPN peer on one end is using policy-based VPN. You must configure a Proxy ID on the Palo Alto Networks firewall. https://docs.paloaltonetworks.com/pan-os/10-1/pan-os-admin/vpns/set-up-site-to-site-vpn/interpret-vpn-error-messages.html

https://live.paloaltonetworks.com/t5/general-topics/wildfire-submission-entries-with-severity-high-showing-action/td-p/143516

• B is the best choice for an SSL Forward Untrust certificate because a self-signed certificate generated on the firewall is not trusted by any client browsers by default1. This means that if the firewall observes an invalid or untrusted security certificate from the server, it will present the self-signed certificate to the client, which will trigger an untrusted certificate warning2. This way, the security admin can ensure that users are aware of any potential risks when accessing HTTPS sites with untrusted certificates.
• A web server certificate signed by the organization’s PKI (A) or a subordinate Certificate Authority certificate signed by the organization’s PKI © are not good choices for an SSL Forward Untrust certificate because they are trusted by the client browsers that have the organization’s root CA installed1. This means that if the firewall observes an invalid or untrusted security certificate from the server, it will present the web server or subordinate CA certificate to the client, which will not trigger an untrusted certificate warning2. This way, the security admin cannot ensure that users are aware of any potential risks when accessing HTTPS sites with untrusted certificates.
• A web server certificate signed by an external Certificate Authority (D) is not a good choice for an SSL Forward Untrust certificate because it is trusted by most client browsers that have the external CA in their trust store1. This means that if the firewall observes an invalid or untrusted security certificate from the server, it will present the web server certificate to the client, which will not trigger an untrusted certificate warning2. This way, the security admin cannot ensure that users are aware of any potential risks when accessing HTTPS sites with untrusted certificates.

Verified References:

• 1: How to Configure SSL Decryption - Palo Alto Networks Knowledge Base
• 2: How to Implement and Test SSL Decryption - Palo Alto Networks Knowledge Base

https://docs.paloaltonetworks.com/pan-os/10-2/pan-os-cli-quick-start/use-the-cli/use-secure-copy-to-import-and-export-files/export-and-import-a-complete-log-database-logdb

Virtual Desktop Infrastructure (VDI) and Virtual Machine (VM) environments, such as Citrix XenApp and XenDesktop or VMWare Horizon and Vcenter, support access natively through HTML5. You can RDP, VNC, or SSH to these machines through Clientless VPN without requiring additional third-party middleware. In environments that do not include native support for HTML5 or other web application technologies supported by Clientless VPN, you can use third-party vendors, such as Thinfinity, to RDP through Clientless VPN. Reference: https://docs.paloaltonetworks.com/globalprotect/10-1/globalprotect-admin/globalprotect-clientless-vpn/supported-technologies

https://networkwiki.blogspot.com/2017/03/palo-alto-networks-clientless-vpn-and.html

In order to see what is in a template, the device-group needs the template referenced. Even if you add the firewall to both the template and device-group, the device-group will not see what is in the template. The following link has a video that demonstrates that B is the correct answer. https://knowledgebase.paloaltonetworks.com/KCSArticleDetail?id=kA10g000000PNfeCAG

Set the Action to take when matching a packet:

Forward—Directs the packet to the specified Egress Interface.

Forward to VSYS (On a firewall enabled for multiple virtual systems)—Select the virtual system to which to forward the packet.

Discard—Drops the packet.

No PBF—Excludes packets that match the criteria for source, destination, application, or service defined in the rule. Matching packets use the route table instead of PBF; the firewall uses the route table to exclude the matched traffic from the redirected port.

https://docs.paloaltonetworks.com/pan-os/10-1/pan-os-admin/policy/policy-based-forwarding/create-a-policy-based-forwarding-rule#ideca3cc65-03d7-449d-b47a-90fabee5293c

The Exceptions settings allows you to change the response to a specific signature. For example, you can block all packets that match a signature, except for the selected one, which generates an alert. The Exception tab supports filtering functions.

If you not believed, then login the firewall go to Vulnerability > Exceptions and select "Show all signatures". From there you will see all threat information including specific actions.

More detail: https://knowledgebase.paloaltonetworks.com/KCSArticleDetail?id=kA10g000000Cm4yCAC

To prevent the import from affecting ongoing traffic when you import the configuration of an HA pair into Panorama, you should disable config sync on both firewalls. Config sync is a feature that enables the firewalls in an HA pair to synchronize their configurations and maintain consistency. However, when you import the configuration of an HA pair into Panorama, you want to avoid any changes to the firewall configuration until you verify and commit the imported configuration on Panorama. Therefore, you should disable config sync before importing the configuration, and re-enable it after committing the changes on Panorama12. References: Migrate a Firewall HA Pair to Panorama Management, PCNSE Study Guide (page 50)

When a URL matches multiple categories, the category chosen is the one that has the most severe action defined below (block being most severe and allow least severe).

1 block

2 override

3 continue

4 alert

5 allow

https://knowledgebase.paloaltonetworks.com/KCSArticleDetail?id=kA10g000000ClsmCAC

https://knowledgebase.paloaltonetworks.com/KCSArticleDetail?id=kA10g000000ClhzCAC

• D is the correct answer because the threat log type would provide information about traffic blocked by a Zone Protection profile. This is because Zone Protection profiles are used to protect the network from attacks, including common flood, reconnaissance attacks, and other packet-based attacks1. These attacks are classified as threats by the firewall and are logged in the threat log2. The threat log displays information such as the source and destination IP addresses, ports, zones, applications, threat types, actions, and severity of the threats2.

Verified References:

• 1: Zone protection profiles - Palo Alto Networks Knowledge Base
• 2: Threat Log Fields - Palo Alto Networks

https://docs.paloaltonetworks.com/panorama/11-0/panorama-admin/manage-log-collection/manage-collector-groups/configure-a-collector-group

"Log redundancy is available only if each Log Collector has the same number of logging disks." (Recommended) Enable log redundancy across collectors if you are adding multiple Log Collectors to a single Collector group. Redundancy ensures that no logs are lost if any one Log Collector becomes unavailable. Each log will have two copies and each copy will reside on a different Log Collector. For example, if you have two Log Collectors in the collector group the log is written to both Log Collectors. Enabling redundancy creates more logs and therefore requires more storage capacity, reducing storage capability in half. When a Collector Group runs out of space, it deletes older logs. Redundancy also doubles the log processing traffic in a Collector Group, which reduces its maximum logging rate by half, as each Log Collector must distribute a copy of each log it receives.

https://docs.paloaltonetworks.com/pan-os/10-2/pan-os-web-interface-help/panorama-web-interface/panorama-device-deployment/manage-software-and-content-updates

https://docs.paloaltonetworks.com/pan-os/10-2/pan-os-web-interface-help/panorama-web-interface/panorama-device-deployment/panorama-dynamic-updates-revert-content

https://knowledgebase.paloaltonetworks.com/KCSArticleDetail?id=kA10g000000ClF4CAK

https://docs.paloaltonetworks.com/pan-os/10-2/pan-os-admin/policy/use-address-object-to-represent-ip-addresses/address-objects

When sizing a decryption firewall deployment, two factors that should be considered are the encryption algorithm and the TLS protocol version. These factors affect the amount of resources and processing power that the firewall needs to decrypt and inspect SSL/TLS traffic.

The encryption algorithm is the method that the server and the client use to encrypt and decrypt the data exchanged in an SSL/TLS session. Different encryption algorithms have different levels of security and performance. For example, AES is a symmetric encryption algorithm that is faster and more efficient than RSA, which is an asymmetric encryption algorithm. However, RSA is more secure than AES because it uses public and private keys to encrypt and decrypt data, while AES uses a single shared key. The firewall must support the encryption algorithms that are used by the servers and clients that it decrypts, and it must have enough CPU and memory resources to handle the decryption workload12.

The TLS protocol version is the standard that defines how the server and the client establish and maintain an SSL/TLS session. Different TLS protocol versions have different features and requirements for encryption algorithms, cipher suites, certificates, handshake messages, etc. For example, TLS 1.3 is the latest and most secure version of TLS, which supports only strong encryption algorithms and cipher suites, such as AES-GCM and ChaCha20-Poly1305, and requires elliptic curve certificates. The firewall must support the TLS protocol versions that are used by the servers and clients that it decrypts, and it must have enough hardware acceleration resources to handle the decryption speed34.

The number of security zones in decryption policies and the number of blocked sessions are not relevant factors for sizing a decryption firewall deployment. The number of security zones in decryption policies only affects how the firewall matches traffic to decryption rules based on source and destination zones, but it does not affect the decryption performance or resource consumption. The number of blocked sessions only indicates how many sessions are denied by the firewall based on security policy or decryption policy rules, but it does not affect the decryption capacity or throughput56.

References: Encryption Algorithms, TLS Protocol Versions, Decryption Policy, PCNSE Study Guide (page 60)

To apply tags automatically based on User-ID logs, the engineer must configure a Log Forwarding profile that specifies the criteria for matching the logs and the tags to apply. The Log Forwarding profile can be attached to a security policy rule or a decryption policy rule to enable auto-tagging for the traffic that matches the rule. The tags can then be used for dynamic address groups, policy enforcement, or reporting1. References: Use Auto-Tagging to Automate Security Actions, PCNSE Study Guide (page 49)

https://docs.paloaltonetworks.com/panorama/11-0/panorama-admin/manage-firewalls/transition-a-firewall-to-panorama-management/migrate-a-firewall-to-panorama-management Push the configuration bundle from Panorama to the newly added firewall to remove all policy rules and objects from its local configuration. This step is necessary to prevent duplicate rule or object names, which would cause commit errors when you push the device group configuration from Panorama to the firewall in the next step.

https://knowledgebase.paloaltonetworks.com/KCSArticleDetail?id=kA10g000000ClRdCAK

https://docs.paloaltonetworks.com/pan-os/10-2/pan-os-admin/url-filtering/configure-url-filtering

https://docs.paloaltonetworks.com/pan-os/10-2/pan-os-admin/url-filtering/allow-password-access-to-certain-sites#id7e63ce07-8b30-4506-a1e3-5800303954e8

https://knowledgebase.paloaltonetworks.com/KCSArticleDetail?id=kA10g000000PNGFCA4

https://docs.paloaltonetworks.com/pan-os/9-1/pan-os-admin/high-availability/ha-concepts/ha-timers

A: https://docs.paloaltonetworks.com/pan-os/10-1/pan-os-web-interface-help/network/network-virtual-routers/more-runtime-stats-for-a-logical-router#id5628a5e4-e908-457e-a2fd-270a476ab752

D: https://docs.paloaltonetworks.com/pan-os/10-2/pan-os-cli-quick-start/cli-cheat-sheets/cli-cheat-sheet-networking

https://knowledgebase.paloaltonetworks.com/KCSArticleDetail?id=kA10g000000Cm1OCAS

https://knowledgebase.paloaltonetworks.com/KCSArticleDetail?id=kA10g000000Cm1OCAS