PCSFE Exam Questions & Answers

Correct Answer: C

Explanation: Traffic is directed to a Palo Alto Networks firewall integrated with Cisco ACI through a policy-based redirect. Cisco ACI is a software-defined network (SDN) solution that provides network automation, orchestration, and visibility. A policy-based redirect is a mechanism that allows Cisco ACI to redirect traffic from one endpoint group (EPG) to another EPG through a service device, such as a Palo Alto Networks firewall. The firewall can then inspect and enforce security policies on the redirected traffic before sending it back to Cisco ACI. Traffic is not directed to a Palo Alto Networks firewall integrated with Cisco ACI by using contracts between endpoint groups that send traffic to the firewall using a shared policy, through a virtual machine (VM) monitor domain, or by creating an access policy, as those are not valid methods for traffic redirection in Cisco ACI. References: Palo Alto Networks Certified Software Firewall Engineer (PCSFE), [Deploy the VM-Series Firewall on Cisco ACI], [Cisco ACI Policy-Based Redirect]

Correct Answer: B

Explanation: Geneve is the protocol used for communicating between VM-Series firewalls and a gateway load balancer in Amazon Web Services (AWS). A gateway load balancer is a type of network load balancer that distributes traffic across multiple virtual appliances, such as VM-Series firewalls, in AWS. Geneve is a tunneling protocol that encapsulates the original packet with an additional header that contains metadata about the source and destination endpoints, as well as other information. Geneve allows the gateway load balancer to preserve the original packet attributes and forward it to the appropriate VM- Series firewall for inspection and processing. VRLAN, GRE, and VMLAN are not protocols used for communicating between VM-Series firewalls and a gateway load balancer in AWS, but they are related concepts that can be used for other purposes. References: Palo Alto Networks Certified Software Firewall Engineer (PCSFE), [Deploy the VM-Series Firewall with AWS Gateway Load Balancer], [Geneve Protocol Specification]

Correct Answer: C

Explanation: Using the management interface as the HA1 backup link helps avoid split brain in active-passive high availability (HA) pair deployment. High availability (HA) is a feature that provides redundancy and failover protection for firewalls in case of hardware or software failure. Active-passive HA is a mode of HA that consists of two firewalls in a pair, where one firewall is active and handles all traffic, while the other firewall is passive and acts as a backup. Split brain is a condition that occurs when both firewalls in an HA pair assume the active role and start processing traffic independently, resulting in traffic duplication, policy inconsistency, or session disruption. Split brain can be caused by network failures, device failures, or configuration errors that prevent the firewalls from communicating their HA status and synchronizing their configurations and sessions. Using the management interface as the HA1 backup link helps avoid split brain in active-passive HA pair deployment. The HA1 interface is used for exchanging HA state information and configuration synchronization between the firewalls. Using the management interface as the HA1 backup link provides redundancy and failover protection for the HA1 interface, ensuring that the firewalls can maintain their HA communication and avoid split brain. Using a standard traffic interface as the HA2 backup, enabling preemption on both firewalls in the HA pair, or using a standard traffic interface as the HA3 link do not help avoid split brain in active-passive HA pair deployment, but they are related features that can enhance performance and reliability. References: Palo Alto Networks Certified Software Firewall Engineer (PCSFE), [High Availability Overview], [Configure HA Backup Links], [Configure Heartbeat Backup]