FCSS_NST_SE-7.6 Exam Dumps - Fortinet NSE 6 - Network Security 7.6 Support Engineer

FortiTelemetry is a critical part of Security Fabric communications and requires explicit configuration for each participating FortiGate interface. The administrative access setting " fabric " (corresponding to FortiTelemetry) must be manually enabled per interface on both upstream and downstream devices. This is performed in the GUI under Administrative Access or via the CLI using the command set allowaccess fabric for the relevant network interface. Without this step, FortiTelemetry communications will not occur on that interface.

Additionally, the default communication between downstream and upstream FortiGate units in the Security Fabric is over TCP port 8013. This port is well-documented as the standard for Security Fabric and FortiTelemetry connections, and must be open and permitted across the network path for connectivity and status enforcement between units. The downstream FortiGate initiates the connection to the upstream via this port unless otherwise configured. This has also been documented as a PCI-relevant port, showing its default usage.

Other options:

Neighbor Discovery in FortiOS uses IPv6 ND protocol, not TCP.

FortiTelemetry port (8013) can be modified, but the interface Administrative Access for the Security Fabric must be manually enabled; Neighbor Discovery port modification is not documented as a supported change for FortiGate.

The best verified answer is C .

The study guide says that when FortiGate is in conserve mode, it activates protection measures to recover memory space:

“System configuration cannot be changed”

“FortiGate skips quarantine actions (including FortiSandbox analysis)”

It also explains that inspection behavior can be reduced while in conserve mode:

“pass (default): All new sessions pass without inspection until FortiGate switches back to non-conserve mode.”

“The av-failopen setting also applies to flow-based antivirus inspection.”

The FortiOS administration guide summarizes this behavior as:

“This causes functions such as antivirus scanning to change how they operate to reduce the functionality and conserve memory without compromising security.”

That is why C is the closest correct choice: FortiGate can reduce functionality of some processes, especially antivirus-related inspection, to preserve memory.

Why the other options are wrong:

A is wrong because FortiGate does not automatically reboot as a default conserve-mode action. A reboot can be configured through an automation stitch , but that is an optional administrator-defined response, not the built-in conserve-mode behavior

B is wrong because the documentation does not say FortiGate switches from proxy-based inspection to flow-based inspection. Instead, it may pass traffic without inspection depending on av-failopen settings

D is not generally correct for conserve mode . The study guide says FortiGate starts dropping new sessions only when memory usage exceeds the extreme threshold : “If memory usage exceeds the extreme threshold, all new sessions that require inspection (flow-based or proxy-based) are blocked.”

So the verified answer is: C .

The correct answers are B and C .

The study guide has a section titled “Not Verified Status on the Collector Agent” and states:

“The collector agent cannot verify if the user is still logged in” and lists these common causes :

“A firewall is blocking traffic to port 139 and 445”

“The workstation remote registry service is not running”

The guide also explains the verification method:

“For WMI polling mode, the collector agent checks the WMI service. For all the other modes, the collector agent checks the HKEY_USERS hive through remote registry services.” If the workstation does not respond to these checks, the status can become not verified

An additional requirements slide in the same study guide confirms:

“TCP ports 139 and 445 must be open between the collector agent and all workstations”

“Remote registry service must be up and running on each workstation”

Why the other options are wrong:

A is wrong because the study guide mentions a workstation coming out of hibernate mode under a different problem: “No Internet After IP Address Change” , not as a common cause of Not Verified status

D is wrong because DNS resolution issues are also discussed under the IP address change scenario, where the collector agent uses DNS to resolve the workstation name after an IP change. That is separate from the Not Verified causes listed for this log message

So the verified answers are: B, C .

The exhibit shows these key lines:

handle_req-Rcvd auth req ... for jsmith in Lab

start_search_dn-base: ' DC=TAC,DC=ottawa,DC=fortinet,DC=com ' filter:sAMAccountName=jsmith

get_all_dn-Found DN 1:CN=John Smith,CN=Users,DC=TAC,DC=ottawa,DC=fortinet,DC=com

The study guide explicitly shows the same LDAP real-time debug pattern and says the request line includes the LDAP server object name:

handle_req-Rcvd auth req ... for jsmith in Lab ...

That supports A : Lab is the configured LDAP server name being used for this authentication request.

For the LDAP flow stage, the study guide states:

“An fnbamd_ldap_build_dn_search_req-base message indicates that FortiGate is performing step two: searching for the user in the LDAP tree.” It also says that if the LDAP server finds the user, the output shows the user’s full DN.

That matches the exhibit’s start_search_dn-base ... filter:sAMAccountName=jsmith and Found DN ... CN=John Smith... lines, so D is correct.

Why the other options are wrong:

B is wrong because the exhibit shows FortiOS has found the user DN CN=John Smith,..., but that does not mean the user is already authenticating with that DN in this step. The study guide says this DN is discovered in step 2 , and only in step 3 does FortiGate bind using the user DN.

C is wrong because the exhibit is showing step 2 (Search Request) , not step 3 (Bind Request) . The study guide separates these steps clearly and shows step 3 with fnbamd_ldap_build_userbind_req-Trying DN ... and __ldap_build_bind_req-Binding to ' CN=John Smith,... '

The correct answer is A .

The debug flow shows:

traffic is going to TCP port 211

FortiGate logs run helper-ftp(dir=original)

The study guide explains exactly what that message means:

“In this example, the run helper-ftp message indicates that the FTP session helper is being used.”

Under normal proxy-based inspection, protocol handling is controlled by Protocol Options . The FortiOS administration guide states:

“Protocol port mapping only works with proxy-based inspection.” and “The ports can be modified to inspect any port with flowing traffic.”

So if the policy is configured for proxy-based inspection but the debug still shows the FTP session helper on port 211, the most likely explanation is that the FTP protocol mapping in Protocol Options is broad enough to match unexpectedly, such as being mapped to Any . That would cause FortiGate to identify the traffic as FTP and invoke the helper.

Why the other options are wrong:

B is wrong because SSL deep inspection is unrelated to this debug. The traffic shown is plain TCP/211 , and the key message is about the FTP helper , not SSL decryption.

C is wrong because if FTP had not been mapped to port 211, FortiGate would be less likely to treat this traffic as FTP. The observed run helper-ftp indicates FTP handling is being triggered.

D is wrong because low-memory conserve behavior would typically cause inspection bypass or blocking behavior, not specifically the run helper-ftp message. The study guide’s helper example ties this message to session-helper use, not memory shortage.

So the verified answer is: A .

To determine the correct reasons for the adjacency failure, we must analyze the standard OSPF real-time debug output (diagnose ip router ospf all enable or diagnose sniffer packet) typically provided in this exam exhibit.

Analyze the Debug Output:

The debug output in this specific question scenario typically displays an incoming Hello packet line: OSPF: RECV[Hello]: ... auth-type 0 ...

" RECV " : Indicates the packet is coming from the Remote peer.

" auth-type 0 " : Indicates the Remote peer is sending " Null " (No) authentication.

Analyze the Failure:

The adjacency fails because the Local FortiGate is rejecting this packet.

If the Local FortiGate accepts " No Authentication " , it would match auth-type 0 and form the adjacency.

Since it is failing (and producing a debug log), the Local FortiGate must be expecting a different authentication type (Type 1 Cleartext or Type 2 MD5).

Evaluate the Options:

A. The remote peer has either OSPF cleartext or MD5 authentication configured.

Incorrect. The debug shows auth-type 0 (No Auth) coming from the remote peer.

B. There is an OSPF authentication configuration mismatch.

Correct. One side is sending " No Auth " (Remote), and the other expects " Auth " (Local). This is a definition of a mismatch.

C. The local FortiGate does not have OSPF authentication configured.

Incorrect. If the Local unit had " No Auth " configured, it would match the Remote ' s auth-type 0, and the adjacency would come up. The failure implies the Local unit does have auth configured.

D. The local FortiGate has either OSPF cleartext or MD5 authentication configured.

Correct. Because the Local unit is rejecting the " No Auth " packet from the remote peer, it confirms that the Local unit has authentication enabled (expecting Type 1 or 2).

Conclusion: The breakdown of the OSPF negotiation shows that the Remote peer is sending no authentication (Type 0), while the Local FortiGate expects authentication, resulting in a mismatch.

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.