NSE5_FSW_AD-7.6 Exam Dumps - Fortinet NSE 5 - FortiSwitch 7.6 Administrator

In FortiSwitchOS 7.6,DHCP snoopingis a Layer 2 security feature that validates DHCP traffic and protects the LAN from rogue DHCP servers. The feature enforces atrust modelon switch ports: ports connected toward legitimate DHCP server infrastructure must be markedtrusted, while edge/access ports facing clients are typicallyuntrusted. When DHCP snooping is enabled on a VLAN (in this case,Student), FortiSwitch inspects DHCP messages and applies filtering rules based on port trust status.

From the exhibit, bothport1(connected to the Linux-Server DHCP server) andport4(connected to the Linux-Client) showDHCP Snooping: Untrusted. In this configuration, the switch treats the DHCP server-facing port as untrusted and, by design, willblock DHCP server-originated messages(such as DHCPOFFER/DHCPACK) arriving on that interface. This prevents the DHCP handshake from completing and effectively stops DHCP from functioning across that VLAN segment. Operationally, this is commonly observed as “no DHCP traffic” at the server/application layer because the exchange cannot progress normally when the server side is not trusted.

Option C is incorrect because the client-facing port is expected to be untrusted. Options A and D do not align with the exhibit: the ports are already placed in the Student VLAN as native VLAN, so the primary issue is the DHCP snooping trust role.

Therefore, the most likely cause is thatport1 is configured as an untrusted port(it must be trusted for a DHCP server), makingBthe correct answer.

According to theFortiSwitchOS 7.6 Administration Guideand theFortiSwitch 7.6 Study Guide, the primary physical constraint when deploying PoE devices is the total power capacity of the switch ' s internal power supply unit (PSU). The provided exhibit shows the PoE status forAccess-1, highlighting three critical metrics: theUnit Power Budget (185.00W), the currentUnit Power Consumption (12.70W), and theUnit Guard Band.

TheUnit Power Budgetrepresents the maximum amount of power the switch can provide to all connected Powered Devices (PDs) simultaneously. As more devices (such as access points, VoIP phones, or cameras) are connected, the cumulative power draw increases. The most important consideration is ensuring that thetotal PoE consumption does not exceed this budget. If the budget is exceeded, the switch will stop providing power to new devices or, depending on the configuration, may shut down lower-priority ports to protect the system hardware.

In this specific exhibit, theUnit Poe Power Modeis set toPriority Based. This means that if the power consumption approaches the budget limit, the switch will use the configured port priorities (seen as " Low " for port1 and port2) to decide which devices to keep powered. TheGuard Band(set to a dynamic value) also plays a role by reserving a small amount of power to handle spikes when devices initialize, further emphasizing that the power budget is a hard limit that must be actively managed by the administrator.

" The tool is a Python script that converts the supported settings in a FortiSwitch standalone configuration file to the equivalent FortiOS settings for a managed switch. " Reference: FortiSwitch 7.6 Study Guide, page 349

According to theFortiSwitchOS 7.6 Administration Guideand theFortiSwitch 7.6 Study Guide, Internet Group Management Protocol (IGMP) snooping is a Layer 2 mechanism that allows a switch to " listen " to IGMP conversations between hosts and routers to maintain a map of which ports require specific multicast streams. When IGMP snooping is enabled, the switch populates aMulticast Layer 2 Forwarding Table(as shown in the exhibit), which ensures that multicast traffic is only forwarded to ports where a receiver has explicitly requested it (e.g., PC1 on port1).

When IGMP snooping isdisabled, the switch no longer maintains this granular forwarding table. By default, a Layer 2 switch that is not performing IGMP snooping treats multicast traffic as if it werebroadcast traffic. Consequently, instead of being intelligently forwarded only to the interested receiver (PC1), the multicast traffic for group 225.1.2.3 will beflooded to all portswithin the same VLAN (VLAN 10). This means PC2, even if it has not joined the group, will receive the multicast packets at the physical layer, leading to unnecessary bandwidth consumption and increased CPU load on unintended recipients.

The documentation explicitly states that disabling IGMP snooping reverts the switch to a " flood-all " behavior for multicast frames within the broadcast domain. Option A is incorrect because the host (PC1) remains a member of the group; only the switch ' s forwarding logic changes. Option B is incorrect as the switch may still see the messages but will not act on them to prune ports. Option D is incorrect as disabling the feature removes the prune/stop mechanism, causing traffic to flow everywhere rather than stopping.

In FortiSwitchOS 7.6,Loop Guardis a Layer 2 loop detection mechanism primarily designed to protect access ports from unintended network loops. In itsoriginal implementation, Loop Guard only detected loops on thenative VLAN, which limited its effectiveness in environments using multiple tagged VLANs. To address this limitation, Fortinet enhanced Loop Guard by introducing theMAC move detection feature, as documented in the FortiSwitchOS 7.6 Administrator Guide.

TheMAC move optioninstructs the FortiSwitch to monitor for repeated MAC address flapping events across ports or VLANs. Such MAC movement is a strong indicator of a Layer 2 loop. However, this enhanced detection mechanism isdisabled by defaultand must be explicitly enabled by configuring aMAC move threshold greater than zero.

According to the FortiSwitchOS 7.6 Administrator Guide (page 164), enabling MAC move allows Loop Guard to detect loops beyond the native VLAN. Furthermore, the guide explicitly states (page 166) thata MAC-Move value of 0 indicates that the MAC move feature is not enabled. This means the switch is not monitoring MAC address movement as part of its loop detection logic, even though Loop Guard itself may still be enabled on the port.

Therefore, a MAC-Move value of 0 does not indicate that Loop Guard is disabled or inactive, nor does it imply VLAN-wide port shutdown behavior. It strictly confirms thatMAC move detection has not been enabled, makingOption Cthe correct and fully verified answer based on FortiSwitchOS 7.6 documentation.

According to theFortiSwitchOS 7.6 Administration Guideand theFortiSwitch 7.6 Study Guide, Multichassis Link Aggregation (MCLAG) and standard Link Aggregation Groups (LAG) are designed to provide link-level and node-level redundancy while presenting a simplified logical view to the Spanning Tree Protocol (STP).

In the provided topology:

Logical Switch View (Option D):Switch 1 and Switch 2 are configured asMCLAG peersconnected via an Inter-Chassis Link (ICL). From the perspective of downstream devices and STP, these two physical switches act as a single logical entity. This prevents STP from seeing a loop between the two switches and the downstream Switch 3, as the redundant physical paths are bundled into a single logical MCLAG trunk.

Logical Interface View (Option B):The exhibit shows Switch 4 connected to Switch 3 via two physical links bundled into aLAG, and Switch 3 connected to the MCLAG peers via split links. In both cases, STP treats the aggregated physical links as asingle logical interface. Because the multiple physical paths are managed by the Link Aggregation Control Protocol (LACP) as one trunk, STP does not block individual ports to prevent loops; instead, it sees one high-bandwidth path.

Regarding the incorrect options:Option Ais false because Switch 3 is an MCLAGclient, not a peer in the group.Option Cis incorrect because Switch 3 and Switch 4 are separate physical and logical nodes; they are not seen as a single client entity by the core.

A FortiLink interface must be enabled on FortiGate (A): To manage a FortiSwitch stack, a dedicated FortiLink interface on the FortiGate is required. This interface is used to manage the communication between FortiGate and the FortiSwitch stack, enabling centralized control and configuration of the switches directly from the FortiGate.

The switch controller feature must be enabled on FortiGate (B): Enabling the switch controller feature on FortiGate allows it to manage connected FortiSwitch units. This feature provides tools and interfaces on the FortiGate for overseeing FortiSwitch configurations, monitoring switch status, and managing network policies across the stack.

All hosts behind an authenticated port are allowed access after a successful authentication (A): Once a device on a port successfully authenticates using 802.1X, all other devices connected behind that port also gain network access. This is typical in scenarios where a switch is behind an authenticated port and not each device individually authenticates.

All devices connecting to FortiSwitch must support 802.1X authentication (D): For a network secured with 802.1X, all devices attempting to connect through the FortiSwitch must support and participate in 802.1X authentication to gain access. This ensures that all devices on the network are authenticated before they are allowed to communicate on the network.