Details
Use a particular source address in Network Time Protocol (NTP) packets.
Rationale:
Set the source address to be used when sending NTP traffic. This may be required if the NTP servers you peer with filter based on IP address.
Impact:
Organizations should plan and implement network time protocol (NTP) services to establish official time for all enterprise network devices. Setting ‘ntp source loopback’ enforces the proper IP address for NTP services.
Solution
Bind the NTP service to the loopback interface.
hostname(config)#ntp source loopback {loopback_interface_number}
Default Value:
Source address is determined by the outgoing interface.
Supportive Information
The following resource is also helpful.
This security hardening control applies to the following category of controls within NIST 800-53: Audit and Accountability.This control applies to the following type of system Cisco.