Fortinet FCSS_NST_SE-7.6 Exam Dumps

The debug flow message iprope_in_check() check failed, drop specifically indicates a failure in the Local-In Policy check. The 'iprope' (IP ROouting Policy Enforcement) engine handles policy lookups. The _in_check suffix confirms that the decision is regarding traffic destined to the FortiGate itself (Local-In traffic), rather than traffic passing through it.

D . The packet was dropped because the requested service is not enabled on FortiGate:

This is the most common cause. When a packet arrives destined for the FortiGate's interface IP (e.g., an HTTPS or SSH request), the kernel checks if that specific service is enabled in the interface settings (set allowaccess). If the service is not enabled (e.g., trying to Ping an interface where PING access is disabled), the iprope_in_check function fails and drops the packet immediately.

C . The packet was dropped because the trusted host list is misconfigured:

Even if the service (e.g., HTTPS) is enabled on the interface, the FortiGate checks the Administrator settings. If Trusted Hosts are configured, the source IP of the incoming packet is compared against the allowed list. If the IP is not on the list, the Local-In policy check (iprope_in_check) fails, and the packet is dropped to secure the management plane.

Why other options are incorrect:

A: If traffic is dropped by a standard Firewall Policy (traffic passing through the device from one interface to another), the debug message will typically state denied by policy x or no matching policy. It would generally be a forward check (iprope_fwd_check or similar), not an _in_check.

B: If there is no route to the source, the error is a Reverse Path Forwarding (RPF) failure. The debug flow logs this explicitly as reverse path check fail, drop.

FortiGate Troubleshooting Guide (Debug Flow): 'The message iprope_in_check() check failed indicates the packet was denied by the Local-In policy. This occurs when traffic destined to the FortiGate is not allowed by the allowaccess configuration or is blocked by Trusted Host settings.'

https://community.fortinet.com/t5/FortiGate/Technical-Tip-Using-the-diagnose-sys-top-CLI-command/ta-p/190238

The correct answers are A and B.

The study guide says:

''If NAT-T is enabled, and there is a FortiGate located in the middle that is running NAT, the sniffer command must use a different filter. In this case, IKE traffic uses UDP port 500, but switches to UDP port 4500 during the tunnel negotiation. Additionally, ESP traffic is encapsulated inside the UDP 4500 channel.''

It also says:

''In some networks, UDP is blocked by firewalls or ISPs. In those cases, you can configure your VPN tunnel to use IKE over TCP in the phase 1 configuration. The default IKE TCP port is 443...''

And the study guide gives the correct capture examples:

No NAT: host <remote-gw> and udp port 500

With NAT and NAT-T: host <remote-gw> and (udp port 500 or udp port 4500)

So:

B is correct because with NAT Traversal enabled, the tunnel may no longer be using only UDP 500. It can move to UDP 4500, so the current filter may miss the traffic.

A is correct because the filter may need to be expanded to include UDP 4500 for NAT-T, or TCP 443 when IKE over TCP is used.

Why the other options are wrong:

C is wrong because restricting the filter to the remote peer IP can make the capture more precise, but it is not required for the sniffer to display output. The problem here is the port/protocol choice, not the lack of a host filter. The study guide examples use host filtering as an aid, not as a requirement.

D is wrong because diagnose debug enable is used to enable real-time debug output for applications, but it does not suppress or invalidate sniffer output. Sniffer capture is a separate command path. Fortinet documentation separately documents diagnose sniffer packet ... for packet capture and diagnose debug enable for debug features.

So the verified answers are: A, B.

https://community.fortinet.com/t5/FortiGate/Troubleshooting-Tip-How-to-troubleshoot-FSSO-agentless-polling/ta-p/214349

From the snippet we can see that FortiGate (via the fssod daemon) is directly detecting the user logon rather than relying on a separate ''collector'' or ''DC agent.'' This indicates agentless polling---FortiGate polls the DC's event logs over TCP 445 to discover logons. So: - FSSO is using agentless polling mode to detect logon events - In agentless mode, FortiGate will periodically poll the same IP (the DC) on port 445 to see if the user is still logged on

The correct answer is C.

The exhibit shows:

562 in ESTABLISHED state

27 in CLOSE state

memory_tension_drop=0

ephemeral=0/131072

According to the study guide, for TCP sessions: ''The protocol state in the session table is a two-digit number. For TCP, the first number (from left to right) is related to the server-side state and is 0 when the session is not subject to any inspection (flow or proxy)... The second digit is the client-side state.'' The same page also shows that value 1 = ESTABLISHED

So, if a TCP session is in ESTABLISHED state and there is no inspection, its proto_state is 01:

first digit 0 = no inspection

second digit 1 = ESTABLISHED

That makes C correct. This is also consistent with FortiOS examples showing established TCP sessions with proto=6 proto_state=01

Why the other options are wrong:

A is wrong because the field that indicates sessions dropped due to low free memory is memory_tension_drop, and in the exhibit it is 0, not 113. The study guide states: ''If there is a lack of free memory, the kernel deletes the oldest sessions. The command shown on this slide displays the number of sessions the kernel deleted because of this mechanism.''

So 113 is the clash value, not memory-tension drops.

B is wrong because ephemeral=0/131072 does not mean 131072 ephemeral sessions were recorded. The study guide explains that FortiGate ''sets a hard limit on the maximum number of ephemeral sessions that can exist at the same time in the session table.''

Therefore:

0 = current ephemeral sessions

131072 = maximum allowed ephemeral sessions for that model/context

D is wrong because the study guide says the temporary retention for possible out-of-order packets happens in state value 5 (TIME_WAIT): ''When a session is closed by both the sender and receiver, FortiGate keeps that session in the session table for a few seconds, to allow for any out-of-order packets that might arrive after the FIN/ACK packet. This is the state value 5.''

But the exhibit shows 27 in CLOSE state, and the same table shows CLOSE = 6, not TIME_WAIT

So the verified answer is C.