[ntp:questions] ntp.conf true and prefer option for server command

suhas manjunath suhasmanjunath32 at gmail.com
Mon Jan 23 06:46:46 UTC 2017


Hi Brian,


Sources marked true are passed by the select process;
> sources marked prefer may be discarded by the select process;
> sources marked true or prefer may be discarded by the cluster process;
> sources marked prefer reaching the combine process will be selected
> as the system source and their offset and jitter used as the system
> values used to discipline the system clock.
>


But the man page of ntp.conf says using true option it will always survive
the selection and clustering algorithms.

*"true* Force the association to assume truechimer status; that is, always
survive the selection and clustering algorithms. This option can be used
with any association, but is most useful for reference clocks with large
jitter on the serial port and precision pulse-per-second (PPS) signals.
Caution: this option defeats the algorithms designed to cast out
falsetickers and can allow these sources to set the system clock. This
option is valid only with the *server* and *peer* commands. "

 So if i use true and prefer option together it has to pass cluster process
also and hence it has to be taken as preferred server. but in our case it
is not taking as preferred server.

Thank you in advance for your time.

Regards,
Suhas


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