Chapter 14 Managing Devices for FortiOS 5.0 : Vulnerability Scan : Requirements for authenticated scanning and ports scanned
  
Requirements for authenticated scanning and ports scanned
The effectiveness of an authenticated scan is determined by the level of access the FortiGate unit obtains to the host operating system. Rather than use the system administrator’s account, it might be more convenient to set up a separate account for the exclusive use of the vulnerability scanner with a password that does not change.
The following sections detail the account requirements for various operating systems.