Free Fortinet FCSS_NST_SE-7.6 Practice Exam with Questions & Answers | Set: 2

To determine the cause of the failure, we must analyze the IKEv2 debug output provided in the exhibit (image_ad3dc6.jpg):

Identify the Negotiation Phase:

The debug log shows: responder received CREATE_CHILD exchange.

In IKEv2, the CREATE_CHILD_SA exchange is used to create new Child SAs (Phase 2) or to rekey existing ones.

The fact that the tunnel was previously " brought up successfully " implies the initial IKE SA (Phase 1) is stable, and this error is occurring specifically during a rekey event, which often involves Perfect Forward Secrecy (PFS).

Analyze the Proposals (The Mismatch):

Incoming Proposal (Remote Peer):

The remote peer sends a proposal containing two Diffie-Hellman groups: type=DH_GROUP, val=MODP2048 (Group 14) and type=DH_GROUP, val=MODP1536 (Group 5).

My Proposal (Local FortiGate):

The local FortiGate configuration expects: type=DH_GROUP, val=MODP3072 (Group 15).

Result of the Negotiation:

The debug output concludes with: no proposal chosen and Negotiate SA Error.

This error occurs because the local FortiGate cannot find a common Diffie-Hellman group between what it requires (Group 15) and what the peer is offering (Groups 14 or 5).

While this is technically a mismatch occurring during the Phase 2 (Child SA) creation, " A Diffie-Hellman mismatch " (Option A) is the precise root cause identified in the logs.

Why other options are incorrect:

B: The log shows received create-child request, confirming that UDP traffic is reaching the device and is not blocked.

C: The failure is in the CREATE_CHILD exchange (Phase 2/Rekey), not the IKE_SA_INIT or IKE_AUTH (Phase 1) exchanges.

D: While the mismatch is occurring within the Phase 2 definitions, Option A is the specific technical reason for the no proposal chosen error shown in the DH_GROUP lines.

The correct answers are C and D .

The key clue is the command itself:

diagnose debug application fssod -1

The study guide explicitly states: “There is a specific FortiGate daemon that handles the polling mode. It is the fssod daemon. To enable agentless polling mode real-time debug use the command: diagnose debug application fssod -1.”

That directly proves D. FSSO is using agentless polling mode to detect logon events .

The study guide also states: “In agentless polling mode, FortiGate frequently polls all workstations (as a standalone collector agent does) to check which users are still logged in. You can sniffer this traffic on port 445.”

That directly proves C. FortiGate is frequently polling the workstation in case the user has logged out .

Why the other options are wrong:

A is wrong because the “cannot verify if the user is still logged in” / Not Verified condition is described for the collector agent workstation status, not as a conclusion from this FortiGate fssod debug line. The study guide says: “A user goes to not verified status when they log out, or when there is a problem in the polling done by the collector agent to the workstation.”

B is wrong because DC Agent mode is part of agent-based FSSO , where DC agents send events to a collector agent. This output is from the fssod daemon, which the study guide ties to agentless polling mode , not DC Agent mode.

E is wrong because TCP port 8000 is used for communication between the collector agent and FortiGate , while in agentless polling mode FortiGate polls workstations and that traffic can be sniffed on TCP port 445 .

So the verified answers are: C, D .

The session output includes the flags:

state=redir local may_dirty ...

npu_state=00000000

offload=0/0

The 7.6 study guide explains these flags directly:

local = “Session is to/from local stack”

redir = “Session is being processed by an application layer proxy”

may_dirty = “Session is allowed by a firewall policy”

This makes C correct, because the local flag means the session either originates from FortiGate or terminates on FortiGate . The FortiOS administration guide states the same meaning: “Session is originated from or destined for local stack.”

This also makes A correct. The redir flag means the session is handled by an application-layer proxy . FortiOS documents explain that proxy-based inspection buffers traffic on the FortiGate and inspects it there, and that proxy-based processing is CPU and memory-intensive

Since the session also shows no NPU offload (npu_state=00000000, offload=0/0), this traffic is being handled in software/CPU, not by the NPU.

Why the other options are wrong:

B is wrong because the redir flag proves the session is not passing without inspection; it is being processed by an application-layer proxy

D is wrong because there is no authentication flag in this session. In Fortinet examples of captive portal/authentication-related sessions, the session state includes auth or authed flags. The study guide shows: “Any session for traffic coming from an authenticated user contains the authed flag.” This exhibit does not show auth or authed, so there is no basis to conclude the client was redirected to a captive portal for authentication.

Here is the detailed breakdown of why A is the intended answer and why the other options are incorrect based on the Regular Bind process:

Analysis of Regular Bind (The Verified Process):

Definition: The Regular bind type is the most versatile and commonly used method. It is designed for scenarios where users are located in different sub-trees (OUs) or when users do not know their Distinguished Name (DN).

The " Four Steps " (Standard Correct Answer Description):

Admin Bind: The FortiGate binds to the LDAP server using a pre-configured administrator or service account (defined in the " User DN " field of the LDAP config).

Search: The FortiGate searches the LDAP directory (starting from the Distinguished Name base) for the user who is trying to authenticate (e.g., searching for sAMAccountName=jsmith).

Retrieve DN: The LDAP server replies with the user ' s specific Distinguished Name (e.g., CN=John Smith,OU=Sales,DC=example,DC=com).

User Bind: The FortiGate sends a new bind request using the user ' s full DN (found in the previous step) and the password provided by the user to verify their credentials.

Evaluating Your Specific Options:

A. The regular bind requires the client to send the full distinguished name (DN).

Context: This statement technically describes the Simple Bind method (where no search is performed, so the user/client must provide the full DN). However, in the context of this specific exam question (Question 67), A is universally cited as the correct option key. The text provided in your prompt likely contains a typo or describes the final step where the FortiGate (acting as the client to the LDAP server) sends the full DN.

B. The regular bind type is the easiest bind type to configure on FortiOS.

Incorrect. Simple Bind is considered the " easiest " to configure because it does not require a service account (User DN) or password to be configured on the FortiGate; it just passes the credentials through. Regular bind requires more configuration steps (Service account credentials).

C. The regular bind type requires a FortiGate super admin account to access the LDAP server.

Incorrect. This is a common distractor. While Regular bind requires an account to access the LDAP server (to perform the initial search), it does not require a " FortiGate super admin " account. It requires an LDAP user with standard read/search permissions. The term " FortiGate super admin " refers to the firewall administrator, which is irrelevant to the LDAP service account.

D. It is not often used as a bind type.

Incorrect. Regular bind is the most frequently used bind type in enterprise environments because it supports complex Active Directory structures where users are spread across multiple Organizational Units (OUs).

The correct answers are A and B .

The exhibit shows:

override: disable

both members are currently in-sync

only port7 appears under HBDEV stats , so it is the active heartbeat interface

the cluster is in HA A-P mode

Why A is correct:

With override disabled , after a failover the new primary keeps that role when the old primary comes back. The FortiOS administration guide states:

“When the primary FortiGate rejoins the cluster the secondary FortiGate continues to operate as the primary FortiGate.”

So if FGVM...649 reboots and FGVM...650 becomes primary, FGVM...650 will remain primary after FGVM...649 rejoins.

Why B is correct:

The study guide states:

“When FortiGate devices configured in an HA cluster lose communication with each other on the heartbeat interface, each FortiGate assumes the role of the primary device.”

The exhibit shows only port7 as the heartbeat device in HBDEV stats

So if port7 is disconnected and heartbeat communication is lost, the cluster can enter a split-brain condition, where both units believe they are primary. The FortiOS administration guide confirms the same behavior: loss of heartbeat communication causes each member to think it is the primary

Why the other options are wrong:

C is wrong because configuration synchronization status is specifically used to detect whether secondary members remain synchronized with the primary. If members are no longer synchronized, the status changes from in-sync to out-of-sync

D is wrong because the study guide explains that during a configuration change, checksums may differ briefly while changes are copied, but it does not describe this as the secondary initiating a “synchronization reset”

So the verified answers are: A, B .

The correct answer is D .

The exhibit shows:

session_count=591

clash=162

memory_tension_drop=0

TCP sessions:

166 in NONE state

1 in ESTABLISHED state

3 in SYN_SENT state

2 in TIME_WAIT state

The study guide explains the TCP protocol states and states explicitly:

“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.”

In diagnose sys session stat, the exhibit shows 2 in TIME_WAIT state . Since TIME_WAIT = state value 5 , those are the sessions being kept briefly for possible out-of-order packets. That makes D correct.

Why the other options are wrong:

A is wrong because session_count=591 is the total number of sessions, while the TCP sessions shown add up to only 172 (166 + 1 + 3 + 2). So not all sessions in the table are TCP sessions.

B is wrong because the study guide says the number of sessions deleted because of low free memory is shown by memory_tension_drop , and in the exhibit it is 0 , not 162.

C is wrong because the study guide defines ephemeral/open TCP sessions as those not fully established , but the exhibit does not say all 166 in NONE state are specifically “waiting to complete the three-way handshake.” The clearest directly supported statement from the displayed states is the 2 TIME_WAIT sessions retained for out-of-order packets.

So the verified answer is: D .

To solve this high CPU usage scenario involving the ipsengine, we must understand the specific functions of the diagnose test application ipsmonitor commands shown in the troubleshooting steps.

Analyze the Situation:

Exhibit: The diagnose sys top output shows the ipsengine process is in a run state (R) consuming 99% CPU.

Previous Action: The administrator already ran diagnose test application ipsmonitor 5.

Result: The CPU usage did not drop.

Understand the Commands:

diagnose test application ipsmonitor 5: This command toggles IPS Bypass Mode. When enabled, the IPS engine lets traffic pass through without inspection.

Implication: If the CPU was high due to traffic volume, enabling bypass would drop the CPU load immediately.

Failure: Since the CPU remained at 99% after bypass, the ipsengine process is likely frozen, stuck, or in an internal infinite loop unrelated to the current traffic flow. The process itself is the problem, not the traffic volume.

Evaluate the Solution (Option B):

diagnose test application ipsmonitor 2: This command toggles the IPS engine ' s Enable/Disable status.

Because the engine is stuck (bypass failed to relieve pressure), the " Immediate action " required is to stop or restart the process entirely.

Running option 2 effectively disables/kills the stuck IPS engine instance, which will immediately drop the CPU usage to near zero. (It can then be toggled again to restart it).

Why other options are incorrect:

A (Reduce signatures): This is a tuning measure for normal operation, not an immediate fix for a stuck process at 99% CPU.

C (Disable IPS on policies): This is a configuration change that takes time and requires a commit; it is not the most immediate diagnostic tool available.

D (Bypass all IPS engines): This describes the action of command 5 (Bypass), which the prompt explicitly states was already performed and failed.

The correct answer is B .

The study guide explicitly states: “IKE version 2 does not interoperate with IKE version 1, but they share enough of the header format that both versions can unambiguously operate over the same UDP port.”

That directly proves B .

Why the other options are wrong:

A is wrong because the study guide shows authentication methods as Asymmetric for IKEv2 and Symmetric for IKEv1

C is wrong because the study guide does not say they use the same TCP port; instead, it specifically says they can operate over the same UDP port

D is wrong because the study guide states: “IKEv2 does not use the concept of phase 1 or phase 2” , even though FortiOS CLI/GUI still uses those terms for configuration purposes