NSE4_FGT_AD-7.6 Fortinet NSE 4 - FortiOS 7.6 Administrator Questions and Answers

Based on the exhibit and the FortiOS 7.6 SSL/SSH Inspection documentation, the correct answer is C.

Understanding the Exhibit Configuration

In the SSL/SSH Inspection Profile, the following settings are shown:

Inspection method: Full SSL Inspection

Server certificate SNI check: Strict

This setting directly controls how FortiGate validates the Server Name Indication (SNI) provided by the client during the TLS handshake.

FortiOS 7.6 Behavior of “Server certificate SNI check”

FortiOS supports three modes for Server certificate SNI check:

Disable

No validation between SNI and server certificate.

Enable

FortiGate checks SNI against the certificate.

If mismatch occurs, FortiGate may still allow the session with reduced validation.

Strict

FortiGate enforces a strict match.

The SNI must match either the CN (Common Name) or one of the SAN (Subject Alternative Name) entries in the server certificate.

If the SNI does not match either CN or SAN, the TLS session is immediately terminated.

The exhibit clearly shows Strict selected.

Why Option C is Correct

With Strict enabled, FortiGate rejects the TLS connection when:

The SNI does not match the CN, and

The SNI does not match any SAN entry

This results in the connection being closed, not allowed with warnings or fallback behavior.

Therefore:

C. FortiGate will close the connection if the SNI does not match the CN or SAN fields is exactly the documented behavior.

Why the Other Options Are Incorrect

A: FortiGate does not fall back to using the CN for URL filtering when Strict is enabled.

B: There is no “accept with warning” behavior in Strict mode.

D: Incorrect logical condition. FortiGate does not require mismatch with both CN and SAN simultaneously; a mismatch with either valid field set is sufficient to close the connection.

According to the FortiOS 7.6 Administration Guide and Fortinet hardware acceleration (NTurbo) documentation, the correct answer is A.

What NTurbo Is (FortiOS 7.6 – Verified)

NTurbo is a hardware-based acceleration feature available on specific FortiGate models. It is designed to improve antivirus and IPS performance when operating in flow-based inspection mode.

NTurbo works by creating a fast, optimized data path between:

FortiGate ingress interface

IPS/AV engine

FortiGate egress interface

This minimizes CPU involvement and reduces packet traversal overhead.

Why Option A Is Correct

A. For flow-based inspection, NTurbo establishes a dedicated data path to redirect traffic between the IPS engine and FortiGate ingress and egress interfaces.

This is exactly how NTurbo works, as documented:

NTurbo applies to flow-based inspection only

It accelerates IPS and antivirus scanning

It creates a dedicated fast path that bypasses unnecessary processing steps

This significantly improves throughput and lowers latency

This description matches Fortinet’s official explanation of NTurbo.

Why the Other Options Are Incorrect

B. NTurbo creates two inspection sessions

Incorrect. NTurbo does not duplicate sessions; it optimizes the packet path.

C. NTurbo offloads traffic to the content processor (proxy-based)

Incorrect. NTurbo does not apply to proxy-based inspection and does not offload to content processors.

D. NTurbo buffers the whole file and then sends it to the antivirus engine

Incorrect. Buffering entire files is a proxy-based behavior, not NTurbo.

In FortiOS 7.6, the Antivirus scan master switch in an antivirus profile becomes available only after at least one supported protocol is enabled for inspection.

What the exhibit shows

A new antivirus profile named FTP_AV_Profile

Feature set: Flow-based

Antivirus scan switch is grayed out

All Inspected Protocols (HTTP, SMTP, POP3, IMAP, FTP, CIFS) are currently disabled

Why the Antivirus scan switch is grayed out

In FortiOS antivirus profiles:

The Antivirus scan toggle is a dependent control

It cannot be enabled unless at least one inspected protocol is selected

This prevents enabling AV scanning when there is no traffic type to scan

This behavior is documented in the FortiOS 7.6 Antivirus Profile configuration section.

Once you enable a protocol (for example, FTP), the Antivirus scan switch becomes active and configurable.

Why option B is correct

B. None of the inspected protocols are active in this profile.

All protocol toggles are OFF

Therefore, FortiGate disables (grays out) the Antivirus scan option

This is expected and correct behavior

Why the other options are incorrect

A. Antivirus scan is disabled under Feature visibilityIncorrect. Feature Visibility controls whether Antivirus appears in the GUI, not whether the scan switch is enabled inside a profile.

C. Feature set must be Proxy-basedIncorrect. Antivirus scanning is supported in both flow-based and proxy-based modes.

D. Less than 2 GB RAM does not support Antivirus scanIncorrect. Memory size affects performance and offloading, not basic AV scan availability.

In the FortiGate Cloud-Native Firewall (CNF) for AWS architecture, traffic from workloads (such as an EC2 instance) in the customer VPC is redirected to the security service (FortiGate CNF) using AWS Gateway Load Balancer (GWLB) technology.

The key AWS component that must exist inside the customer VPC to steer workload traffic to the GWLB is the:

Gateway Load Balancer Endpoint (GWLBe)

This endpoint is what the customer VPC routes point to (for example, default route or subnet route entries), enabling transparent insertion of the FortiGate CNF inspection path for EC2 traffic.

Why the other options are not correct:

A: CNF does not “create the customer VPC” (that is customer-owned), and “GWLBe” is the only relevant created item here, not the whole VPC.

C: Customer VPC is not created by CNF, and GWLB is typically part of the CNF service side; the question specifically asks what must be created to handle traffic from the EC2 instance (that requires GWLBe in the customer VPC).

D: CNF does not create the Internet Gateway (IGW) in the customer VPC, and IGW is not the required CNF-created component for steering traffic to FortiGate CNF.

The exhibit shows the output of the following command:

diagnose test application ipsmonitor 1

pid = 2044, engine count = 0 (+1)

0 - pid:2074:2074 cfg:1 master:0 run:1

How to interpret this output (FortiOS 7.6 – IPS internals)

ipsmonitor displays the status of IPS engines running on the FortiGate.

engine count = 0 means:

No IPS scanning engines are currently active

IPS is not processing any traffic

In FortiOS, IPS engines are started on demand.

Critical documented behavior

IPS processes are only spawned when at least one firewall policy is configured with an IPS profile and traffic matches that policy.

If no firewall policy references an IPS profile, the IPS engine:

Does not start

Shows engine count = 0

Appears “not working,” even though the IPS profile exists

This is exactly what the diagnose output indicates.

Why option A is correct

A. There is no firewall policy configured with an IPS security profile.

Creating an IPS profile alone is not sufficient

IPS must be applied to an active firewall policy

Traffic must match that policy for the IPS engine to run

Otherwise, ipsmonitor will show engine count = 0

This matches FortiOS 7.6 IPS operational behavior.

Why the other options are incorrect

B. Administrator entered the command diagnose test application ipsmonitor 5.

Incorrect.

The exhibit clearly shows ipsmonitor 1

Using a different argument would not explain engine count = 0

C. FortiGate entered into IPS fail open state.

Incorrect.

In fail-open, IPS engines may be bypassed, but they still initialize

engine count = 0 specifically indicates IPS is not in use at all

D. Administrator entered the command diagnose test application ipsmonitor 99.

Incorrect.

The command argument affects debug level, not engine creation

Again, the exhibit shows ipsmonitor 1

In FortiOS 7.6, SD-WAN steering decisions are recorded in traffic logs only when traffic matches an explicit SD-WAN rule (SD-WAN service rule). When no configured SD-WAN rule matches a session, FortiGate uses the implicit (default) SD-WAN rule/behavior to select a member (often resulting in load-balancing or default selection based on the configured SD-WAN algorithm).

In the exhibit, traffic is permitted by firewall policy ID 1, and the Destination Interface alternates between port1 and port2, but SD-WAN Rule Name remains empty. This is consistent with the sessions being forwarded by the implicit SD-WAN rule, which does not populate a named rule in the log columns.

Why the other options are not correct:

A: SD-WAN rule name logging is not a “delayed display” behavior requiring refresh; it is populated per-session when an explicit rule matches.

B: Application Control is not required for SD-WAN rule name to appear. Rule name logging depends on SD-WAN rule match, not on whether Application Control is enabled.

C: Feature visibility affects GUI display options, but the exhibit already shows the SD-WAN columns enabled; the issue is that no explicit SD-WAN rule is being hit.

According to the FortiOS 7.6 Study Guide and technical documentation regarding High Availability (HA), the FortiGate Clustering Protocol (FGCP) uses a specific set of rules to elect the primary unit in a cluster. By default, the election order follows: Connected Monitored Ports > HA Uptime > Priority > Serial Number.

However, when the HA override setting is enabled, the election logic is modified to prioritize the administrator-defined priority value over the uptime of the cluster members. In this specific configuration, the election process follows this sequence:

Connected monitored ports: The unit with the most functioning monitored interfaces is preferred.

Priority: The unit with the highest manually configured priority value (e.g., 255) is selected next.

HA uptime: If monitored ports and priority are equal, the unit that has been up in the HA cluster the longest is chosen.

FortiGate serial number: As a final tie-breaker, the unit with the higher serial number is elected.1

Statement A is correct because it reflects the shift where Priority is evaluated immediately after monitored ports, overriding the standard uptime advantage. Statements B and D are incorrect because the FGCP uses HA uptime, not system uptime, for its calculations.

In FortiOS 7.6, if an administrator wants to block traffic only after an IPS signature is triggered a specific number of times within a defined time window, this must be done using IPS filters with rate-based settings.

Why option D is correct

IPS filters allow administrators to match signatures based on attributes such as:

Severity

Protocol

CVE

Signature ID

IPS filters support rate-based actions using:

rate-mode periodical

rate-count

rate-duration

With rate-mode periodical, FortiGate:

Counts how many times a signature is triggered

Within a defined time period

And applies the configured action (for example, block) once the threshold is exceeded

This directly matches the requirement:

“block traffic that triggers the signature set number of times during a specific time period.”

Why the other options are incorrect

A. IPS group signatures, set rate-mode 60Group signatures do not provide the required per-period rate-based blocking logic.

B. IPS packet logging optionLogging does not enforce blocking behavior.

C. IPS signatures, rate-mode periodical optionRate-based controls are applied via IPS filters, not directly on individual signature definitions.

In FortiOS 7.6, when FortiGate is integrated with FortiAnalyzer and FortiManager, firewall policies rely on a Universally Unique Identifier (UUID) to ensure proper policy tracking, synchronization, and log correlation across devices.

Why the UUID is required

Every firewall policy in FortiOS has a UUID.

FortiManager uses the UUID to:

Track policies across managed FortiGate devices

Maintain policy consistency during installs and revisions

FortiAnalyzer uses the UUID to:

Correlate logs accurately to the correct firewall policy

Preserve log association even if policy order or policy ID changes

Without a UUID:

Policy-to-log mapping can break

FortiManager cannot reliably manage or synchronize policies

FortiAnalyzer log analysis becomes inconsistent

This is explicitly documented in Fortinet administration and logging architecture references.

Why the other options are incorrect

B. Policy IDPolicy ID can change when policies are moved and is not reliable for long-term correlation across FortiManager and FortiAnalyzer.

C. Sequence IDSequence ID reflects GUI ordering only and has no role in log correlation.

D. Log IDLog ID is generated per log event, not per firewall policy.

From the exhibits:

The firewall policy has NAT enabled and is configured to Use Dynamic IP Pool.

The selected IP pool (Internet-pool) is configured as:

Type: One-to-One

External IP Range: 100.65.0.110–100.65.0.111 (only two public IPs)

PC1 and PC2 can access the internet because each one-to-one NAT mapping consumes one public IP from the pool. When PC3 is added, there is no third public IP available in the pool, so FortiGate cannot allocate a one-to-one mapping for PC3 and the session fails.

FortiOS behavior here is standard: with one-to-one IP pools, the available pool size limits how many distinct internal sources can be translated concurrently (depending on allocation and sessions), and a pool with only two IPs will not reliably support three separate hosts needing translations.

Therefore, the administrator can fix this in two valid ways:

B. In the IP pool configuration, set end ip to 100.65.0.112.

This expands the pool by adding an additional public IP address, making three public IPs available (.110, .111, .112), so PC3 can be assigned an address for one-to-one NAT.

D. In the IP pool configuration, set type to overload.

Changing the pool type to overload enables PAT (many-to-one), allowing multiple internal hosts (PC1, PC2, PC3) to share the pool address(es) using different source ports. This removes the “one public IP per internal host” limitation inherent to one-to-one pools.

Why the other options are not correct:

A. Multiple Interface Policies is unrelated to IP pool exhaustion and does not solve NAT allocation limits.

C. match-vip affects VIP matching behavior for destination NAT/virtual IP usage and does not address the source NAT pool shortage causing PC3 to fail.

In FortiOS 7.6, firewall policies can be displayed in multiple views to help administrators understand and manage rules more effectively. The difference in ordering between Interface Pair View and By Sequence View is intentional and documented.

Why the policy order is different

Interface Pair View

Groups firewall policies based on the incoming (From) and outgoing (To) interfaces.

Policies are organized under interface pairs such as:

LAN → WAN

WAN → LAN

Within each interface pair, policies may appear reordered compared to the global list.

This view is designed for readability and troubleshooting, not to show execution order.

By Sequence View

Displays firewall policies in their actual evaluation (processing) order.

This is the top-down order FortiGate uses when matching traffic.

It reflects the real rule sequence that determines which policy is hit first.

Why option C is correct

C. Interface Pair View sorts policies based on matching interfaces, while By Sequence View shows the actual processing order of rules.

This statement exactly matches FortiOS behavior as documented in the FortiOS 7.6 Firewall Policy Views section of the Administrator Guide.

Why the other options are incorrect

A: Interface Pair View does not follow traffic logs, and By Sequence View is not based on “rule priority” grouping.

B: FortiGate does not dynamically reorder policies based on traffic patterns.

D: Security levels do not affect policy ordering in Interface Pair View.

According to the FortiOS 7.6 High Availability (HA) Administration Guide and FGCP (FortiGate Clustering Protocol) requirements, the correct answers are B and D.

FGCP HA Cluster Mandatory Requirements (FortiOS 7.6)

When forming an HA cluster using FGCP, FortiGate devices must meet several strict compatibility and configuration requirements. Among the options given, the following two are mandatory:

✅ B. They must have the same number of configured VDOMs

In FortiOS HA, all cluster members must have the same VDOM configuration.

This includes:

Same number of VDOMs

Same VDOM names

This is required so configuration synchronization can occur correctly between members.

If VDOM counts differ, HA formation will fail.

✔ This is explicitly required and documented.

✅ D. They must have the same HA group ID

The HA group ID uniquely identifies an HA cluster on the network.

All FortiGate units intended to join the same cluster must share the same HA group ID.

If the group IDs differ, devices will not recognize each other as cluster peers.

✔ This is a fundamental FGCP requirement.

Why the Other Options Are Incorrect

❌ A. They must have the same hard drive configuration

Hard drive presence or size does not have to match for FGCP HA to function.

Disk differences may affect logging behavior, but they do not prevent HA cluster formation.

Therefore, this is not a required condition.

❌ C. They must have the heartbeat interfaces in the same subnet

Heartbeat interfaces must be:

Directly connected

In the same Layer 2 broadcast domain

They do not require IP addressing or being in the same IP subnet.

In many deployments, heartbeat interfaces have no IP addresses at all.

Therefore, “same subnet” is not a documented requirement.

With a dialup IPsec VPN on FortiGate, when add-route is enabled, FortiGate will only install the corresponding route when it has enough negotiated information from the tunnel. In FortiOS 7.6, that means the route is tied to the Phase 2 (Quick Mode) selectors and is created dynamically when the IPsec SA is actually up.

B. The administrator must ensure phase 2 is successfully established

This is required. FortiGate does not install the add-route route just because Phase 1 exists or because the configuration is present. The route is added when the tunnel is effectively usable, which requires Phase 2 (IPsec SA) to be up. If Phase 2 is not established, there is no active SA and FortiGate will not inject the related route into the routing table.

So, if the static route is not showing, one correct explanation is that Phase 2 is not up.

C. The administrator must define the remote network correctly in the phase 2 selectors

This is also required. For dialup tunnels, FortiGate derives what route to add from the remote subnet(s) defined in the Phase 2 selector (proxy ID). If the remote network in Phase 2 is missing, incorrect, or too broad/too narrow in a way that prevents negotiation, the tunnel either won’t come up (so no route), or the route that would be installed won’t match what the administrator expects.

So, another correct explanation is that the Phase 2 remote network is not correctly defined, preventing the correct route from being created.

Why the other options are incorrect

A. Policy route instead of a static route

Add-route does not require policy routes. It is specifically a feature that injects a route (route-table entry) associated with the IPsec tunnel/SA and the Phase 2 selector networks.

D. Enable a dynamic routing protocol

Dynamic routing protocols (OSPF/BGP/RIP) are not required for add-route. Add-route is independent of dynamic routing and works by installing routes locally based on the negotiated selectors.