Free Fortinet FCSS_NST_SE-7.6 Practice Exam with Questions & Answers

The correct answers are A and B .

The Network Security Support Engineer 7.6 Study Guide states under OSPF Troubleshooting :

“Follow these steps to troubleshoot an OSPF problem between two peers:

Check that the local router can reach the remote peer. IP addresses must be in the same subnet and have the same subnet mask.

Ensure that IP protocol 89 is not blocked.

Hello and dead intervals must match.

The OSPF router ID for each peer must be unique. Duplicate router IDs are not allowed.

Do the MTUs match?

If authentication is enabled, the type and password must match on both sides.”**

The same page also summarizes the troubleshooting tips as:

“Do peers have an IP address within the same subnet?”

“Is IP protocol 89 blocked?”

This directly confirms:

A is correct

B is correct

Why the other options are wrong:

C is wrong because TCP port 179 is used by BGP , not OSPF. OSPF uses IP protocol 89 , as the study guide explicitly notes

D is wrong because the study guide’s OSPF adjacency troubleshooting checklist does not require an active static route to the peer. OSPF neighbors form adjacency on directly reachable networks, and the guide instead focuses on same subnet, protocol 89, intervals, router ID, MTU, and authentication matching

So the verified answers are: A, B .

The correct answers are A and D .

The debug output shows:

Sent RADIUS req to server ' RadiusServer ' : IP=172.25.188.164 ... user= " student " using CHAP

Result for radius svr ' RadiusServer ' 172.25.188.164(0) is 0

Sending result 0 for req 2

The study guide explains that in RADIUS real-time debug, FortiGate shows the IP address of the RADIUS server it is querying. In the example, it says FortiGate “creates an access request to the RADIUS server at IP address 10.0.13.130” and shows the line Sent radius req to server ... IP=10.0.13.130

So in your exhibit, the queried server is clearly 172.25.188.164 , which makes A correct.

The study guide also states:

“The message fnbamd_comm_send_result-Sending result 0 indicates that the authentication was successful and that FortiGate received the Access-Accept message.”

Since your exhibit also ends with Sending result 0 , that makes D correct.

Why the other options are wrong:

B is wrong because result 0 means authentication successful , not failed

C is wrong because the debug explicitly shows using CHAP , and the study guide lists supported RADIUS schemes as CHAP, PAP, MS-CHAP, and MS-CHAPv2

E is wrong because the study guide says two-factor authentication would involve an Access-Challenge response: “If two-factor authentication is enabled on the server, the response is an Access-Challenge message” Your exhibit shows successful result 0 / Access-Accept , not a challenge.

So the verified answers are: A, D .

The get router info bgp summary output lists BGP neighbor status:

Prefix Reception: The " State/PfxRcd " column shows the number of prefixes received from the neighbor—neighbor 100.64.1.254 has " 1 " , confirming option A.

Received Message Count: Under " MsgRcvd " , 18 packets have been received from neighbor 100.64.1.254. This matches option C.

The second neighbor 100.64.2.254 is in " Active " state and has received/sent 0 packets, indicating that its TCP connection is NOT established, disproving option B.

There is no indication anywhere that the router is " still calculating " prefixes; " Active " just means no session is established, so option D is incorrect.

The correct answer is D .

In the exhibit, get router info routing-table database shows both static default routes:

0.0.0.0/0 [20/0] via 100.64.2.254, port2

0.0.0.0/0 [10/0] via 100.64.1.254, port1

But get router info routing-table all shows only:

0.0.0.0/0 [10/0] via 100.64.1.254, port1

The study guide explains that get router info routing-table all displays the routes that make it to the FIB — the best active routes . It also says that this command doesn’t show standby or inactive routes , which can remain only in the routing table database. It gives the exact rule: “when two static routes to the same destination subnet have different distances, the one with the lower distance is installed in the routing table, and the one with the higher distance is installed in the routing table database.”

The study guide also shows the route selection process:

Most specific route

Lowest distance

Lowest metric (dynamic routes)

Lowest priority (static routes)

ECMP

So the port2 default route is absent from the second output because its distance is 20 , while the port1 default route has distance 10 . The lower-distance route is installed in the active routing table/FIB.

Why the other options are wrong:

A is wrong because the exhibit does not indicate port2 is down or disabled.

B and C are wrong because priority is checked only after distance for static routes. Here, the routes already differ by distance , so priority is not the deciding factor.

So the verified answer is: D .

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 path the traffic will take, we must look at the FortiGate Route Lookup Precedence (Packet Processing Flow) and the specific configurations shown in the exhibit

Analyze the Routing Precedence:

In FortiOS, when a packet arrives (and is not part of an existing session), the FortiGate performs route lookups in a specific order:

Policy Routes: Configured under config router policy (or diagnose firewall proute list). These are checked first. If a packet matches the criteria (Source, Destination, Protocol, Incoming Interface), the Policy Route is used immediately, bypassing the standard routing table.

FIB (Forwarding Information Base): If no Policy Route matches, the device looks at the standard routing table (Static, Connected, Dynamic).

Analyze the Exhibit:

Policy Route Section: The output of diagnose firewall proute list shows an active policy route (id=1).

Destination: 100.65.0.0/255.255.255.0 (Matches the network in the question).

Action: It directs traffic to gateway 10.0.4.253 via oif=6(port4).

Routing Table Section: The output of get router info routing-table database shows multiple routes for 100.65.0.0/24 (Static, OSPF, BGP) all with distance 10. The Static route (S) is currently selected (* > ) in the FIB.

Conclusion:

Because Policy Routes take precedence over the standard routing table (FIB), the FortiGate will forward the traffic using the instructions in Policy Route ID 1. It will not use the Static, BGP, or OSPF routes visible in the routing table for any traffic that matches the policy route ' s criteria (ingress port 3).

To understand why Type 5 LSAs (AS External LSAs) are missing from the Link-State Database (LSDB), we must look at how OSPF generates and propagates them:

A. There is no autonomous system border router (ASBR) in the network:

Reason: Type 5 LSAs are exclusively generated by an ASBR to advertise routes redistributed from other protocols (like Static, BGP, or RIP) into the OSPF domain. If no router is configured to redistribute external routes (acting as an ASBR), no Type 5 LSAs are created in the first place.

C. The local router is located in a stub area:

Reason: By definition, a Stub Area (and a Totally Stubby Area) prevents Type 5 LSAs from entering. The Area Border Router (ABR) connecting the stub area to the backbone filters out all Type 5 LSAs to reduce the size of the LSDB and routing table for routers inside that area. Instead, a default route is usually injected.

Why other options are incorrect:

B: While database filtering exists, standard prefix-list filtering typically affects the routing table (RIB) generation, not the underlying LSDB propagation of Type 5 LSAs, or it is less common than the architectural reasons (Stub/No ASBR).

D: IP Protocol 89 is the transport for OSPF itself. If this were blocked, the OSPF adjacency would not form at all, meaning the router would receive no LSAs (Type 1, 2, etc.), not specifically just Type 5.

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 .