The set log-checksum sha256 command configures the FortiAnalyzer to generate a hash value using the SHA-256 algorithm for each log file upon rolling (archiving). This hash value is then stored alongside the log file. The direct function enabled by this command is the creation and recording of this hash. While the ultimate purpose is to allow for integrity verification, the command itself only facilitates the recording step. The term "authentication code" is used loosely here; the primary function is recording the hash for integrity purposes.

B: The command configures a hashing algorithm (SHA-256) for integrity, not an encryption algorithm for confidentiality. Log transfer encryption is a separate feature.

C: The secure channel for the OFTP (OveR-the-wire FortiTelemetry Protocol) process is established using SSL/TLS encryption, which is unrelated to the checksum configuration for archived log files.

D: This describes the ultimate goal, but not the direct action of the command shown. The command enables the recording of the hash; the verification is a separate, subsequent step performed using a different diagnose command.

1. FortiAnalyzer Administration Guide 7.4.1

Log Security

p. 110.

"FortiAnalyzer can checksum log files to ensure that they have not been tampered with. When a log file is rolled

FortiAnalyzer calculates a checksum and stores it. You can later verify the log file against the checksum to confirm that the log file has not been changed." This quote shows that the process involves calculating and storing (recording) the checksum.

2. FortiAnalyzer CLI Reference 7.4.1

config system global

p. 113.

The description for set log-checksum is "Set the checksum algorithm for rolled logs." This confirms the command's role is to configure the algorithm for the checksumming process.

3. FortiAnalyzer CLI Reference 7.4.1

diagnose log checksum

p. 45.

The existence of the diagnose log checksum command demonstrates that verification is a distinct action from the configuration command shown in the question.