The output of the diagnose sys session list command provides the critical evidence needed to determine the behavior during a failover:
Session Synchronization (synced):
The most important indicator in the exhibit is the synced flag located in the state= line (state=may_dirty synced none app_ntf).
In FortiOS HA (High Availability), the synced flag confirms that this specific session has been successfully synchronized from the primary device to the secondary (backup) device.
Session synchronization (Session Pickup) ensures that if the primary unit fails, the secondary unit already has the session in its table and can resume traffic processing immediately.
TCP State (proto_state=01):
The output shows proto=6 (TCP) and proto_state=01.
In the FortiGate session table, proto_state=01 for TCP indicates that the session is in the ESTABLISHED state (post-three-way handshake).
This invalidates Option B, which claims the TCP session is not fully established.
Failover Outcome:
Because the session is ESTABLISHED and SYNCED, the secondary device will seamlessly take over the session upon primary failure.
The traffic continues to flow through the new primary without requiring the user/client to restart the connection. This is the primary function of HA Session Pickup.
Why other options are incorrect:
A: While the output shows app_ntf (Application Control notification) and may_dirty, the presence of the synced flag overrides this concern regarding failover. If the session type were not supported for failover (e.g., certain proxy sessions in older versions), it would not be marked as synced. Since it is synced, it persists.
B: As noted, proto_state=01 means established, not " not fully established " .
D: While the kernel updates routing tables, the purpose of syncing the session is to preserve the state so it does not need to be re-evaluated as a new packet would, preventing traffic drops.
Reference:
FortiGate Security 7.6 Study Guide (High Availability): " If session pickup is enabled, the primary unit synchronizes its session table... to the backup unit. If the primary unit fails, the backup unit... continues to process the sessions with no interruption. "

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.
Reference:
FortiGate Security 7.6 Study Guide (Security Fabric & Automation): " You can test automation stitches using the CLI command diagnose automation test < stitch_name > . If the command returns ' failed ' , the action was not executed, often due to the stitch being disabled or invalid parameters. "

The correct answer is A .
The study guide explains the IKEv2 exchange order very clearly:
* "The initial exchanges are: IKE_SA_INIT and IKE_AUTH."
* "Create_Child_SA exchange: Creates a new child SA or rekeys an existing child SA." It also states:
* "After successful IKE_SA_INIT and IKE_AUTH exchanges, the CHILD_SA exchange takes place. In this exchange, the peers negotiate the CHILD_SA and the traffic selectors - traffic selector responder (TSr) and traffic selector initiator (TSi)." That is why A is correct: if the tunnel was initially brought up successfully , then the initial exchanges already succeeded. A later problem during CREATE_CHILD_SA , especially with traffic selectors/phase 2 selectors , can cause the tunnel to fail during rekey or child-SA renegotiation.
Why the other options are wrong:
* B is wrong because proposal mismatch for the IKE SA is handled during IKE_SA_INIT , not after the tunnel is already up. The study guide says IKE_SA_INIT negotiates the security settings to protect the IKE traffic
* C is wrong because a pre-shared key mismatch is part of authentication and would prevent successful initial establishment during IKE_AUTH . The study guide shows that after IKE_AUTH,
"authentication succeeded" and "established IKE SA" when it works
* D is wrong because a Diffie-Hellman mismatch belongs to IKE_SA_INIT , which happens before the tunnel comes up. The study guide also states: "By IKEv2 design, no Diffie-Hellman public key is exchanged during an IKE_AUTH exchange." So the verified answer is: A .

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