In current versions of the NTP software package the ntpq command line utility supports a :config keyword which can be used to change ntpd's configuration dynamically at runtime.
In order to avoid reconfiguration by unauthorized folks ntpd has to be configured properly for symmetric key authentication, and an appropriate key ID and password have to be specified when using the ntpq command. The command syntax is the :config keyword followed by a command as used in the ntp.conf file. For example, the following commands can be entered at the ntpq interactive command prompt to add an upstream NTP server and remove a different one:
:config server 172.16.3.10 iburst minpoll 6 maxpoll 6 :config unconfigure 172.16.3.10
The commands above replace the addpeer and delpeer commands used with the ntpdc utility with older versions of the NTP package.
See also:
— Martin Burnicki 2016-02-29 15:58