From the exhibit, you can observe that the debug output captures an IKEv1 negotiation in aggressive mode.
Let ' s break down the supporting details in line with official Fortinet IPsec VPN troubleshooting resources and debug guides:
For Option B:
The very first line of the debug output shows:
comes 10.0.0.2:500- > 10.0.0.1:500, ifindex=7.
This indicates the traffic direction-from the remote IP (10.0.0.2) with port 500 to the local IP (10.0.0.1) with port 500. According to Fortinet ' s documentation, the right side of the arrow always represents the local FortiGate gateway. Thus, 10.0.0.1 is the local gateway IP address.
For Option D:
You see the statement:
negotiation result " remote "
and
received peer identifier FQDNCE88525E7DE7F00D6C2D3C00000000
Official debug documentation describes that the " peer identifier " or peer ID sent by the initiator is displayed here. In the context of IKE/IPsec negotiation, this value is used as the IPsec peer ID for authentication and identification purposes. The initiator is providing " remote " as the peer ID for its connection.
Why Not A or C:
Perfect Forward Secrecy (PFS): The debug does not show any DH group negotiation in phase 2 (no reference to group2, group5, etc., for phase 2), so you cannot deduce the presence of PFS solely from this output.
Phase 2 negotiation: The log focuses on IKE (phase 1) negotiation and establishment; there's no reference to ESP protocol, Quick Mode, or other identifiers that would show phase 2 SA negotiation and establishment.
This interpretation aligns with the explanation in the FortiOS 7.6.4 Administration Guide ' s VPN section and the official debug command output samples published in Fortinet's documentation. It demonstrates how to distinguish between local and remote addresses and how to identify the use of peer IDs.
References:
FortiOS 7.6.4 Administration Guide: IPsec VPN and Debugging VPNs
Technical Support Resources on interpreting IKE debug output and peer ID roles

The 8.8.8.8/32 route is visible in the OSPF database on FGT-B but not installed into the routing table-the most likely explanation is that FGT-B is filtering it from being installed.

When FortiGate performs SSL certificate inspection with default settings, it checks if the Server Name Indication (SNI) matches either the Common Name (CN) or any Subject Alternative Name (SAN) in the server certificate. If there is no match, FortiGate does not block the connection; instead, it uses the CN value from the certificate's subject field to continue web filtering and categorization.
This behavior is described in the official Fortinet 7.6.4 Administration Guide:
"Check the SNI in the hello message with the CN or SAN field in the returned server certificate: Enable: If it is mismatched, use the CN in the server certificate." This is the default (Enable) mode, which differs from the Strict mode that would block the mismatched connection.
By default, this policy ensures service continuity and prevents disruptions due to certificate mismatches, allowing FortiGate to log and inspect based on the CN even when the requested SNI does not match. It provides a balance between connection reliability and the accuracy of filtering by certificate identity, allowing security policies to remain functional without unnecessary blocks. This approach is recommended by Fortinet to maintain usability for end-users while still supporting granular inspection.
References:
FortiGate 7.6.4 Administration Guide: Certificate Inspection
SSL/SSH Inspection Profile Configuration

The correct answers are C and D .
For D , the session output shows proto=6, which means TCP, and proto_state=01. The study guide explains that for TCP sessions, "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." It also shows that value 1 = ESTABLISHED So proto_state=01 means:
* first digit 0 = no inspection
* second digit 1 = ESTABLISHED
That confirms the TCP session has been successfully established.
For C , the study guide section "Session for an Authenticated User" states: "Any session for traffic coming from an authenticated user contains the authed flag. Additionally, the username is added to the session information." In the exhibit, the session contains user=User1 and an authentication state flag (authd), which indicates the session is associated with an authenticated user.
Why the other options are wrong:
* A is wrong because the session did match a firewall policy . The study guide says the session output includes "The ID of the matching policy" In the exhibit, the session shows policy_id=1 , so a firewall policy was matched.
* B is wrong because the study guide explains the gwy field as:
* first value = gateway to destination
* second value = gateway to source The exhibit shows gwy=10.1.0.254/10.1.10.1, so:
* gateway to destination = 10.1.0.254
* gateway to source = 10.1.10.1
So the verified answers are: C, D .

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.
Reference:
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. "