Fortinet Updated NSE5_FSW_AD-7.6 Exam Questions and Answers by bernie

The information in the " Native VLAN " column for port23 on the FortiSwitch indicates that a standalone switch is connected to it. This is because the column displays " $424MPTF20000027, " which matches the format of a Fortinet device serial number.

Here ' s a breakdown of the evidence in the image:

Native VLAN:The " Native VLAN " column typically displays the VLAN ID for untagged traffic on a trunk port. However, in this case, it shows a serial number format ( " $424MPTF20000027 " ).

No Trunk Information:The " Trunk " column is blank for port23, indicating it ' s not configured as a trunk member.

Other Ports:Port1 and port2 show " default " in the " Native VLAN " column, which is the expected behavior for access ports.

Fortinet FortiSwitch devices typically don ' t display the serial number of adjacent FortiSwitch devices in the " Native VLAN " column. This column is reserved for VLAN information on trunk ports.

In a FortiLink-managed switching architecture, the FortiGate firewall acts as the centralized controller for downstream FortiSwitch devices. TheFortiSwitch Faceplatesview in the FortiGate GUI provides a physical-style representation of switch ports, including port numbers, operational status, link state, speed, duplex, and connected neighbor information. According to FortiOS 7.6 and FortiSwitchOS 7.6 documentation fromFortinet, this port-level intelligence is derived fromLink Layer Discovery Protocol (LLDP)advertisements received from the FortiSwitch.

LLDP is an IEEE 802.1AB standard protocol used for vendor-neutral Layer 2 neighbor discovery. FortiSwitch periodically sends LLDP frames that include detailed port descriptors such as chassis ID, port ID, port description, system name, system capabilities, and VLAN-related attributes. When FortiGate receives these LLDP advertisements over the FortiLink interface, it correlates the information with the managed FortiSwitch inventory and renders accurate port details in the Faceplates view.

Other options are incorrect for the following reasons. The FortiSwitch model alone is insufficient to populate per-port operational details. Cisco Discovery Protocol (CDP) is a Cisco-proprietary protocol and is not used by FortiGate for Faceplates visualization. FortiLink discovery frames are used to establish and maintain the FortiLink management relationship, but they do not carry the granular per-port metadata required for the Faceplates display.

Therefore, the Faceplates view relies specifically onLLDP advertisements received from the FortiSwitch, making optionCthe correct and fully verified answer based on FortiOS 7.6 and FortiSwitchOS 7.6 behavior.

According to theFortiSwitchOS 7.6 Administration Guideand theFortiSwitch 7.6 Study Guide, the Routing Monitor provides a comprehensive view of the Routing Information Base (RIB), which includes all routes learned via static configuration or dynamic protocols (OSPF, BGP, etc.). However, not every route present in the RIB is active for traffic forwarding. The switch must select the " best " path for any given destination to be installed into theForwarding Information Base (FIB).

The provided exhibit shows a routing table with multiple sources for the same destination. Specifically, there is aStaticdefault route ($0.0.0.0/0$) with an administrative distance of 220, and anOSPFdefault route ($0.0.0.0/0$) with an administrative distance of 110. In FortiSwitchOS routing logic, when multiple routes to the exact same destination exist, the system compares theirAdministrative Distance (AD). The route with the lowest AD is considered the most " preferred " or " trustworthy " .

In this case, the OSPF route ($AD 110$) is more preferred than the Static route ($AD 220$). Consequently, the OSPF route is marked with a green checkmark in theFIBcolumn, while the Static route—despite being " Available " in the RIB—is excluded from the FIB. The same logic applies to the $10.0.100.0/30$ subnet, where theConnectedroute is preferred over the OSPF learned route for the same destination. Therefore, the status reflects standard route selection behavior where less-preferred routes remain in the RIB as backups but are not used for active forwarding.

In FortiSwitchOS 7.6,Dynamic ARP Inspection (DAI)is tightly integrated withDHCP snoopingto provide Layer 2 protection against ARP spoofing and man-in-the-middle attacks. DAI relies on theDHCP snooping binding table, which contains trusted IP-to-MAC-to-port mappings learned from legitimate DHCP transactions. Because of this dependency, the trust model for DAI is directly inherited from DHCP snooping.

According to the FortiSwitchOS 7.6 Administrator Guide, when a switch port is configured astrusted for DHCP snooping, that same port isautomatically treated as trusted by DAI. No additional configuration is required. This implicit trust relationship exists because trusted DHCP snooping ports are assumed to be connected to legitimate infrastructure devices such as DHCP servers, routers, or upstream network devices that must be allowed to send valid ARP replies.

On untrusted ports, DAI inspects ARP packets and validates them against the DHCP snooping database. If an ARP packet does not match an existing binding, it is dropped. On trusted ports, ARP packets bypass DAI inspection to ensure normal network operation and to avoid blocking valid infrastructure traffic.

The other options are incorrect. There is no separate CLI command required to trust a port for DAI (Option A). IP Source Guard (Option C) is another Layer 2 security feature that also depends on DHCP snooping but is not required to establish DAI trust. Static MAC learning (Option D) is unrelated to DAI trust behavior.

Therefore, once a port is configured as trusted for DHCP snooping,DAI implicitly trusts the port, makingOption Bthe correct and fully verified answer based on FortiSwitchOS 7.6 documentation.