Fsx and Audit logs

In-order to audit access to files and folders you will have to set audit controls on the files and folders that you want audited for user access attempts. You can configure audit controls using the Windows-native GUI interface or programmatically using Windows PowerShell commands. If inheritance is enabled, you typically need to set audit controls only on the top-level folders you want to log accesses for.

You can also refer the link below for additional details. https://docs.aws.amazon.com/fsx/latest/WindowsGuide/file-access-auditing.html#faa-gui-interface