The FortiGate device must synchronize internal information system clocks using redundant authoritative time sources.

The loss of connectivity to a particular authoritative time source will result in the loss of time synchronization (free-run mode) and increasingly inaccurate time stamps on audit events and other functions. Multiple time sources provide redundancy by including a secondary source. Time synchronization is usually a hierarchy; clients synchronize time to a local source while that source synchronizes its time to a more accurate source. The network device must utilize an authoritative time server and/or be configured to use redundant authoritative time sources. This requirement is related to the comparison done in CCI-001891. DoD-approved solutions consist of a combination of a primary and secondary time source using a combination or multiple instances of the following: a time server designated for the appropriate DoD network (NIPRNet/SIPRNet); United States Naval Observatory (USNO) time servers; and/or the Global Positioning System (GPS). The secondary time source must be located in a different geographic region than the primary time source.

Log in to the FortiGate GUI with Super-Admin privilege. 1. Open a CLI console, via SSH or available from the GUI. 2. Run the following command: # show full-configuration system ntp | grep server The output should be: set server {IP address of NTP server 1} set server {IP address of NTP server 2} If the internal information system clocks are not configured to synchronize with the primary and secondary time sources, this is a finding.

Log in to the FortiGate GUI with Super-Admin privilege. 1. Open a CLI console, via SSH or available from the GUI. 2. Run the following command: # config system ntp # set ntpsync enable # set type custom # set syncinterval {INTEGER} To add NTP server 1: # config ntpserver # edit {ID} # set server {IP ADDRESS} # set authentication enable # set key {PASSWORD} # set key-id {INTEGER} # next To add NTP server 2: # config ntpserver # edit {ID} # set server {IP ADDRESS} # set authentication enable # set key {PASSWORD} # set key-id {INTEGER} # next # end