Free Fortinet NSE5_FSW_AD-7.6 Practice Exam with Questions & Answers

According to theFortiSwitchOS 7.6 Administration Guideand theFortiSwitch 7.6 Study Guide, Multichassis Link Aggregation (MCLAG) provides node-level redundancy by grouping two physical switches together so that theyappear as a single logical switchto the rest of the network. This logical representation is critical for preventing Spanning Tree Protocol (STP) from blocking redundant uplinks from downstream client switches.

To achieve this "single switch" appearance, the MCLAG peer switches synchronize their STP state andshare the same Bridge ID, which consists of a synchronized bridge MAC address and the same bridge priority. As shown in the exhibits for Core-1 and Core-2, both switches are configured with aBridge MAC of 02090f000701and aPriority of 20480. Because they possess identical identification parameters, each physical switch in the peer group locally recognizes itself as part of the root bridge entity for the MSTP region.

This behavior is intentional and is a fundamental characteristic of MCLAG design in FortiSwitchOS. It ensures that any downstream device, such as Access-1, receives BPDUs with the same bridge ID from both Core-1 and Core-2, thereby treating them as a single high-availability neighbor rather than two separate devices. Option A is incorrect as FortiGate typically does not participate in STP calculations. Option B is incorrect because this "duplicate" root behavior is the expected sign of acorrectlyfunctioning MCLAG control plane. Option D is incorrect as STP remains active to prevent loops elsewhere in the fabric; it is merely logically simplified for the MCLAG domain.

According to theFortiSwitchOS 7.6 Administration Guideand theFortiSwitch 7.6 Study Guide, 802.1X port security allows administrators to define specific actions based on the outcome of an authentication attempt. The configuration exhibit shows a security policy named "Students" with two specialized VLAN assignments enabled: aGuest VLANand anAuthentication fail VLAN.

In FortiSwitchOS 7.6, these two settings serve distinct purposes based on the client's behavior:

Guest VLAN (Option C):This is used when a connected device doesnothave an 802.1X supplicant (software) or does not respond to EAP (Extensible Authentication Protocol) requests within the specified "Guest authentication delay". In this scenario, the device is moved to the "onboarding" VLAN to allow for basic network access or software downloads.

Authentication fail VLAN (Option A):This is triggered specifically when a devicedoesattempt to authenticate via 802.1X but the authentication server (RADIUS) returns anAccess-Rejectmessage, typically due toincorrect credentials.

As stated in the scenario, the userattemptsto authenticate but enters thewrong credentials. According to the policy shown in the exhibit, theAuthentication fail VLANis enabled and set to"quarantine.fortilink (quarantine)". Therefore, the FortiSwitch will logically move the port's traffic into the quarantine VLAN, isolating the user from the production network due to the failed login attempt. Option B is incorrect as there is no "shutdown" action configured, and Option D refers to a default state that is overridden by the explicit failure policy.

To cause endpoints to exchange PoE information and negotiate power with the managed FortiSwitch via LLDP, you should configure the LLDP profile to include power management in the advertised LLDP-MED TLVs. Here are the steps:

Access the LLDP Profile Configuration:Start by entering the LLDP profile configuration mode with the command:

config switch-controller lldp-profile

edit "LLDP-PROFILE"

Enable MED-TLVs:Ensure that MED-TLVs (Media Endpoint Discovery TLVs) are enabled. These TLVs are used for extended discovery relating to network policies, including PoE, and are essential for PoE negotiation. They include power management which is crucial for the negotiation of PoE parameters between devices. The command to ensure network policies are set might look like:

set med-tlvs network-policy

Add Power Management TLV:Specifically add or ensure the power management TLV is part of the configuration. This will advertise the PoE capabilities and requirements, enabling dynamic power allocation between the FortiSwitch and the connected devices (like VoIP phones or wireless access points). This can typically be done within the network-policy settings:

config med-network-policy

edit

set poe-capability

next

end

Save and Apply Changes:Exit the configuration blocks properly ensuring changes are saved:

End

Verify Configuration:It’s always good practice to verify that your configurations have been applied correctly. Use the appropriateshoworgetcommands to review the LLDP profile settings.

By adding the power management as part of LLDP-MED TLVs, the FortiSwitch will be able to communicate its power requirements and capabilities to the endpoints, thereby facilitating a dynamic power negotiation that is crucial for efficient PoE utilization.

When loop guard is enabled on port1 and port2 configured with the same native VLAN (VLAN 10), there are specific scenarios under which port1 can be shut down due to loop guard operation:

A.port1 was shut down by loop guard protection.Loop guard is a specific feature used in network environments to prevent alternative or redundant loops. When loop guard is active, it can shut down a port if it stops receiving BPDU (Bridge Protocol Data Units) on a port that is expected to receive them, assuming a loop or link failure and putting the port into an inconsistent state to prevent potential loops.

B.STP triggered a loop and applied loop guard protection on port1.If the Spanning Tree Protocol (STP) detects a loop or loss of BPDU transmissions while loop guard is enabled, it will proactively shut down the port to prevent network instability or a broadcast storm. This is an essential function of loop guard within the context of STP, providing additional protection against topology changes that could introduce loops.

According to theFortiSwitchOS 7.6 Administration Guideand theFortiLink 7.6 Study Guide, the Spanning Tree Protocol (STP) is automatically enabled on managed FortiSwitches to ensure a loop-free Layer 2 topology within the FortiLink fabric. When multiple physical paths exist between switches (as shown in the redundant connections between the Core and Access tiers), STP must block one of the paths to prevent a broadcast storm.

The behavior described in the exhibit—whereport3 on Access-1enters aDiscarding state—is a result of the STP election process. In a standard STP environment, switches elect aRoot Bridgebased on the lowestBridge Priority(or lowest MAC address as a tie-breaker). Once a root is established, other switches identify the "best" path to that root (the Root Port) and block all other redundant paths.

The provided exhibit shows that Access-1 has two paths to the core: one to Core-1 and one to Core-2. The fact that the path to Core-2 is discarded suggests that the STP topology was recalculated when Core-2 was enabled. In the context of Fortinet technical exams for this specific scenario,Option C (Core-2 has the lowest bridge priority)is the standard answer identifying that Core-2's priority settings influenced the STP tree such that Access-1's link to it was determined to be the redundant (alternate) path.

If the switches were configured withMCLAG (Multi-Chassis Link Aggregation), both physical links would be treated as a single logical trunk, and neither would be in a discarding state. However, without MCLAG, the system relies on bridge priorities to prune the loop.BPDU Guard (Option A)is incorrect because it would administratively shut down the port rather than placing it in an STP "Discarding" state.Option Bis incorrect as the switch would not appear in the managed topology if unauthorized.

FortiSwitch supports packet capture through various methods, but the Sniffer profile is specifically capable of capturing traffic on both trunks and management interfaces.Here's why:

Sniffer Profile (B):

Versatile Capture:The sniffer profile in FortiSwitch is designed to capture traffic across different types of interfaces, including trunks (where multiple VLANs are present) and management interfaces (used for controlling and monitoring the switch).

Configuration Flexibility:You can configure sniffer profiles to target specific traffic, offering flexibility in monitoring and troubleshooting network issues on both data and management planes.

Other Options:

SPAN (A)is used mainly for mirroring traffic to another port for analysis but is typically limited in its ability to capture management interface traffic.

sFlow (C)andTCP dump (D)are useful tools but do not specifically align with the capability to universally capture traffic across trunks and management interfaces in the context described.

In dynamic routing on FortiSwitch, certain types of interfaces are utilized to participate in the routing processes. The types of interfaces that can be used include:

Loopback Interfaces (B):Loopback interfaces are virtual interfaces that are always up, making them ideal for use in routing protocols where a stable interface is necessary. They are commonly used to establish router IDs and manage routing information more reliably.

Switch Virtual Interfaces (C):Switch Virtual Interfaces (SVIs) are assigned to VLANs and can have IP addresses assigned to them, making them capable of participating in Layer 3 routing. SVIs are essential for routing between different VLANs on a switch and can participate in dynamic routing protocols to advertise networks or make routing decisions.

Physical Interfaces (D)andDetected Management Interfaces (A)are not typically used directly by dynamic routing protocols for their operations in the context of FortiSwitch.

It provides benefits that can be obtained when using 802.1X authentication (C): MAC, IP, and protocol-based VLANs on FortiSwitch are beneficial in network environments where additional granularity is needed in traffic segmentation and security, similar to what can be achieved through 802.1X authentication. These VLAN types allow for dynamic assignment of ports to VLANs based on the characteristics of the incoming traffic, enhancing both security and network efficiency.

"MSTP is based on RSTP", so the same port role election and the same root bridge selection. Reference: FortiSwitch 7.2 Study Guide, page 187

According to theFortiSwitchOS 7.6 Administration Guideand theFortiSwitch 7.6 Study Guide, Dynamic ARP Inspection (DAI) is a security feature used to intercept, log, and discard ARP packets with invalid IP-to-MAC address bindings. DAI is primarily used to prevent "Man-in-the-Middle" attacks, such as ARP spoofing or ARP cache poisoning.

In this scenario, DAI is active on VLAN 10. When DAI is enabled, the FortiSwitch intercepts all ARP packets on untrusted ports and validates them against a trusted source—most commonly theDHCP snooping database. As shown in the "DHCP Snooping database" exhibit, PC2 is correctly mapped to IP 10.0.10.30 and MAC 00:09:0F:AB:00:0B.

When PC2 attempts to send a forged ARP reply claiming that IP 10.0.10.254 (the FortiGate's IP) is located at its own MAC address (00:09:0F:AB:00:0B), the FortiSwitch's DAI engine inspects the packet. It checks the DHCP snooping database for a binding that matches IP 10.0.10.254 to MAC 00:09:0F:AB:00:0B. Finding no such valid entry (because the database correctly identifies the MAC 00:09:0F:AB:00:0B as belonging to IP 10.0.10.30), the switch identifies the ARP packet as illegitimate.

Consequently, the FortiSwitch willdrop the ARP repliesbecause they fail the DAI validation check against the established DHCP snooping bindings. Option A is incorrect as DAI functions independently of IPSG once the database is populated. Option B is incorrect because "accepting" the spoofed packet is the opposite of DAI's purpose. Option C is incorrect because DAI is specifically designed to run on untrusted ports to protect the network from client-side attacks.