CISC-ND-001030 - The Cisco router must be configured to synchronize its clock with the primary and secondary time sources using redundant authoritative time sources - NTP_SERVER_2


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.


Configure the Cisco router to synchronize its clock with redundant authoritative time sources as shown in the example below.

R2(config)#ntp server x.x.x.x
R2(config)#ntp server y.y.y.y

See Also

Item Details


References: 800-53|AU-8(2), 800-53|AU-8b., CAT|II, CCI|CCI-001889, CCI|CCI-001890, CCI|CCI-001893, Rule-ID|SV-215838r835117_rule, STIG-ID|CISC-ND-001030, STIG-Legacy|SV-105441, STIG-Legacy|V-96303, Vuln-ID|V-215838

Plugin: Cisco

Control ID: 44ae0d98cfb28d32f0ecdac46894656ab1f4ac641438136865b196705edb0551