CASA-ND-000940 - The Cisco ASA must be configured to synchronize its clock with the primary and secondary time sources using redundant authoritative time sources - ntp server prefer

Information

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.

Solution

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

ASA(config)# ntp server 10.1.48.8 prefer
ASA(config)# ntp server 10.1.22.2
ASA(config)# end

See Also

https://dl.dod.cyber.mil/wp-content/uploads/stigs/zip/U_Cisco_ASA_Y24M07_STIG.zip

Item Details

Category: AUDIT AND ACCOUNTABILITY

References: 800-53|AU-8b., CAT|II, CCI|CCI-001890, CCI|CCI-004922, CCI|CCI-004923, CCI|CCI-004928, Rule-ID|SV-239924r991813_rule, STIG-ID|CASA-ND-000940, Vuln-ID|V-239924

Plugin: Cisco

Control ID: 5789abeda40fa4c14d57910bf00663fc7a6ad87bcc925556ff97c68d19fedbed