Fortinet Network Security Expert NSE4_FGT_AD-7.6 Reddit Questions

In FortiSASE site-based (remote internet access) deployments, FortiExtender is used to onboard branch or remote sites without a local FortiGate.

According to FortiSASE and FortiExtender architecture documentation:

FortiExtender integrates with FortiSASE using a secure VXLAN-over-IPsec tunnel

This tunnel:

Extends the site network to FortiSASE

Transparently forwards traffic for inspection

Preserves network segmentation and routing context

This design is similar to cloud-based LAN extension and is not proxy-based

Why the other options are incorrect

B: FortiClient is used for agent-based user access, not FortiExtender

C: Secure Web Gateway (SWG) is a service, not a transport mechanism

D: PAC files and explicit proxies are used in agentless / proxy-based access, not site-based FortiExtender deployments

From the HA configuration shown for HQ-NGFW-1:

set memory-based-failover enable

set memory-failover-threshold 70

set memory-failover-monitor-period 50

set memory-failover-sample-rate 10

set memory-failover-flip-timeout 60

set override disable

set priority 200

From the performance status outputs:

HQ-NGFW-1 memory used is 90% (well above the configured threshold of 70%)

HQ-NGFW-2 memory used is about 48.7% (well below the threshold)

What happens in FortiOS 7.6 with memory-based failover

When memory-based failover is enabled, FortiGate monitors memory utilization. If the unit’s memory usage stays above the configured memory-failover-threshold for the configured memory-failover-monitor-period, the cluster triggers a failover away from the unit under memory pressure.

Threshold = 70%

HQ-NGFW-1 is at 90%, so it violates the threshold.

Monitor period = 50 seconds.

The administrator observed for 55 seconds, which is longer than 50 seconds, so the condition is met for long enough to trigger failover.

The memory-failover-flip-timeout 60 is used to prevent rapid back-and-forth role changes (flapping) after a failover decision; it does not prevent the initial failover from occurring once the threshold breach persists for the monitor period.

In FortiOS 7.6, when a FortiGate is operating in NAT mode, physical interfaces that participate in traffic forwarding (such as LAN and DMZ) must meet certain fundamental requirements.

Correct statements

D. Both interfaces must have IP addresses assigned.

Correct

In NAT mode, FortiGate operates as a Layer-3 device.

Every interface that forwards traffic must have an IP address.

Without an IP address:

The interface cannot participate in routing

Firewall policies cannot be applied correctly

This is a mandatory requirement.

C. Both interfaces must have directly connected routes on the routing table.

Correct

When an IP address is assigned to an interface, FortiGate automatically installs a connected route for that subnet in the routing table.

These connected routes are required so FortiGate:

Knows how to reach the locally attached networks

Can forward traffic between LAN and DMZ

While administrators do not manually create these routes, their presence is required for correct operation.

Why the other options are incorrect

A. Both interfaces must have DHCP enabled and roles assigned.

Incorrect

DHCP is optional; interfaces can use static IPs.

Interface roles (LAN, DMZ, WAN) are administrative/GUI aids, not functional requirements.

B. Both interfaces must have the interface role assigned.

Incorrect

Interface roles affect GUI grouping and some default behavior.

They are not required for NAT mode operation or traffic forwarding.

In FortiOS 7.6 Application Control, security logs are generated primarily for actions such as Block or Monitor, not for Allow actions.

What is happening in the exhibit

An Application Override is configured for ABC.Com

Type: Application

Action: Allow

The application control profile is applied to a firewall policy

Logging is enabled on the firewall policy

Traffic to ABC.Com is successfully allowed

However, no security logs appear for ABC.Com.

Why no logs are generated

In FortiOS 7.6:

Application Control logs are written to Security Logs when:

An application is Blocked

An application is Monitored

When an application action is set to Allow:

The traffic is permitted silently

No application control security log is generated

Even if policy logging is enabled

This is expected and documented behavior.

To generate logs for allowed applications, the action must be set to Monitor, not Allow.

Why the other options are incorrect

A. ABC.Com is hitting the category Excessive-BandwidthIncorrect. ABC.Com has a higher-priority explicit override (priority 1), so it is not evaluated against the Excessive-Bandwidth filter.

B. The ABC.Com Type is set as Application instead of FilterIncorrect. Application-type overrides are valid and commonly used; this does not suppress logging.

C. The ABC.Com must be configured as a web filter profileIncorrect. This traffic is being evaluated by Application Control, not Web Filter.