Fortinet Updated FCSS_NST_SE-7.6 Exam Questions and Answers by aqsa

The Internet Key Exchange version 2 (IKEv2) protocol simplifies the negotiation process compared to IKEv1. It is defined by a specific sequence of message exchanges to establish a secure IPsec tunnel.

The correct chronological order of the IKEv2 exchanges is:

IKE_SA_INIT (Initial Exchange):

This is the first exchange. It negotiates the security parameters for the IKE Security Association (IKE SA), sends nonces, and performs the Diffie-Hellman key exchange. At the end of this exchange, the communication is encrypted, but the peers are not yet authenticated.

IKE_AUTH (Authentication Exchange):

This is the second exchange. It authenticates the previous messages, exchanges identities and certificates (if used), and establishes the first Child SA (the actual IPsec Security Association used for data traffic).

CREATE_CHILD_SA (Subsequent Exchanges):

This exchange occurs after the IKE SA and the initial Child SA are established. It is used to create additional Child SAs (for different traffic selectors) or to perform re-keying for the IKE SA or existing Child SAs.

Why other options are incorrect:

A & B: Incorrect because CREATE_CHILD_SA cannot happen before the SA is initialized (IKE_SA_INIT) and authenticated (IKE_AUTH).

D: Incorrect because IKE_AUTH cannot occur before IKE_SA_INIT.

Therefore, the protocol flow is IKE_SA_INIT $\rightarrow$ IKE_AUTH $\rightarrow$ CREATE_CHILD_SA.

The partial output from diagnose hardware sysinfo memory provides details on system RAM allocation. According to Fortinet's technical documentation for memory troubleshooting and Linux memory management (which FortiOS is based on):

MemFree is the portion of physical memory not currently allocated to any running process or kernel function. Thus, 708880 kB is available and can be immediately used by user-space programs or system operations.

Inactive refers to pages in the memory cache that were previously in use for I/O or file system buffering but are now not actively referenced. These pages are retained in memory for quick access if needed again, but can be reclaimed for other memory operations if demand increases. The value 98908 kB here represents currently unused cache pages (inactive pages), ready for repurposing or deletion if the system requires more RAM.

Cached represents the total amount of system memory allocated to cache, which includes both active and inactive cache pages. It does not, by itself, represent I/O cache exclusively, nor does "inactive" mean memory “will never be used” as the kernel can re-purpose inactive pages on demand.

We must analyze the specific CLI output provided in the exhibit to determine the observations.

Analyze the Command and Output:

Command: # diagnose automation test HAFailOver

This command is used to manually trigger an automation stitch (named "HAFailOver") to verify its configuration and action execution. It simulates the trigger event to run the defined actions.

Output: automation test failed(1). stitch:HAFailOver

The output explicitly states that the test failed. The code (1) is a general error code indicating the execution did not complete successfully.

Evaluate the Options:

A. The configuration was backed up:

Incorrect. Since the test result is "failed", the action defined in the stitch (which we can infer from the name "HAFailOver" is likely "Backup Configuration") was not successfully performed.

B. A high availability (HA) failover occurred:

Incorrect. The command diagnose automation test is a simulation tool. It does not indicate that a real physical HA failover took place; it only attempts to run the script associated with that event.

C. The test was unsuccessful:

Correct. The output clearly reads "automation test failed(1)", which is the definition of an unsuccessful test.

D. The automation stitch test is not being logged:

Correct. In the context of Fortinet automation troubleshooting, a "failed(1)" result often occurs if the stitch is disabled or if the logging configuration required to trigger or record the stitch is not active. Consequently, the test execution is not properly logged in the automation history, or the failure implies a lack of necessary logging data to proceed. By elimination of the clearly incorrect options A and B, D is the second valid observation.