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V-234183

CAT II (Medium)

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

Rule ID

SV-234183r987682_rule

STIG

Fortinet FortiGate Firewall NDM Security Technical Implementation Guide

Version

V1R5

CCIs

CCI-000366, CCI-001893

Discussion

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.

Check Content

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.

Fix Text

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