Fortinet Updated NSE4_FGT_AD-7.6 Exam Questions and Answers by lockie

From the routing table in the exhibit, there is already a static route for 172.20.1.0/24 pointing out port3 with:

Distance = 9

Priority = 2

Type = Static

In FortiOS, route selection prefers (in order) the route with the lowest administrative distance to a destination. Therefore, to make traffic to 172.20.1.0/24 go through port2 only, the administrator must ensure the port2 static route is more preferred than the existing port3 route.

Why C is correct

C. The existing static route through port3 must have the distance set to 11.

If the existing port3 route distance is increased to 11, then a new port2 route with distance 9 will be preferred (9 < 11). This makes the port3 route a backup route instead of the active one.

Why D is correct

D. The new static route must have the distance set to 9

Setting the new port2 route distance to 9 (and increasing the port3 route to 11 as in option C) ensures FortiGate selects the port2 route as the best route for 172.20.1.0/24.

Why A and B are not correct

A (priority 3): By itself it does not guarantee selection over the existing route, and FortiOS route choice is driven primarily by distance.

B (metric 1): Metric is not the primary selector for static route preference compared to administrative distance in this scenario.

So the two criteria that achieve the objective are:

Make the existing port3 route less preferred by increasing its distance (C)

Ensure the new port2 route uses the preferred distance (D)

According to the FortiOS 7.6 Administrator Study Guide, the Application Control engine processes traffic by evaluating the Application and Filter Overrides section first, using a top-down matching logic similar to firewall policies. In the provided exhibit, there are two override entries:

Priority 1: A behavior-based filter for Excessive-Bandwidth with the action set to Block.

Priority 2: A vendor-based filter for Apple with the action set to Monitor.

The exhibit titled "Application override configuration" explicitly shows that Apple FaceTime is one of the signatures included within the Excessive-Bandwidth behavior filter. When the FortiGate inspects FaceTime traffic, it matches the first entry (Priority 1) because the signature belongs to the "Excessive-Bandwidth" group. Since the action for this priority is Block, the traffic is dropped immediately.

The phrase "only a few calls" is a common exam distractor; in this context, the "Excessive-Bandwidth" filter refers to the classification of the application (as one that typically consumes high bandwidth) rather than a real-time measurement of the specific session's throughput. Because the engine stops searching once a match is found in the overrides, it never reaches the Priority 2 "Monitor" rule or the general Category settings.

Comprehensive and Detailed 150 to 200 words of Explanation From Exact Extract of FortiOS 7.6 documents:

According to the FortiOS 7.6 Administration Guide, the firewall policy ID is a unique numerical identifier assigned to each policy for internal database tracking and management purposes. It is important to distinguish the policy ID from the policy sequence. While the FortiGate processes traffic based on a top-down approach (the sequence), the policy ID itself does not determine the order of execution (Statement A is incorrect).

In FortiOS, once a policy is committed to the configuration, the policy ID cannot be modified (Statement B). If an administrator needs to change a policy ID, they must either delete and recreate the policy or use the clone command in the CLI to copy the settings to a new ID.

Furthermore, the CLI provides a specific shortcut for policy creation: you can create a policy with ID 0 (Statement C). When the command edit 0 is used within the config firewall policy context, the FortiOS kernel automatically assigns the next available integer as the policy ID. This is a standard practice for efficient configuration via the command line. Statement D is incorrect because, while every policy must have an ID, the GUI automatically generates this value without requiring the user to manually provide or even see it during the initial creation process.

Based on the diagnose debug rating output provided in the exhibit and the standard behavior of the FortiGuard connection mechanism in FortiOS 7.6:

Weight Calculation (Statement A is True):

In FortiOS, the rating server selection process uses a weight-based system.

According to official documentation, the weight increases with failed packets (lost responses) and decreases with successful packets.

This mechanism ensures that servers with poor reliability are penalized by having higher weights, effectively pushing them to the bottom of the preference list.

Default Port Communication (Statement D is True):

The exhibit explicitly shows the communication is using HTTPS on port 8888.

In FortiOS 7.6 (and legacy versions like 6.2/6.4), FortiGuard filtering supports specific protocols and ports: HTTPS on ports 443, 53, and 8888, where 8888 is considered a default port for FortiGuard queries.

Ports 53 and 8888 are standard for both UDP and TCP/HTTPS FortiGuard communications to avoid common firewall blocks on standard web ports.

Why other options are incorrect:

Statement B (Unreliable protocols): While you can configure UDP (which is unreliable), the exhibit specifically shows HTTPS is being used, which is a reliable (TCP-based) protocol.

Statement C (DNS lookup): In the "Flags" column of the server list, a server found via DNS lookup would be marked with the "D" flag. The exhibit shows the flag as "I" (indicating the last INIT request was sent to this server) and a numeric "2," but the "D" flag is absent. Additionally, the IP 10.0.1.241 is a private address, suggesting it is a manually configured FortiManager or local override server rather than a public server found via global DNS lookup.