[ntp:questions] stepping and slewing

Harlan Stenn stenn at ntp.isc.org
Sat May 12 23:25:10 UTC 2007

>>> In article <slrnf4cdbu.e4.serge.bets at laposte.net>, Serge Bets <serge.bets at NOSPAM.laposte.invalid> writes:

Serge> Ntpdate doesn't touch the frequency at all. It slews the phase
Serge> offset, period. But you are free to preset the frequency via "ntptime
Serge> -f", and get something nearer to the "ntpd -gq" level. However
Serge> ntpdate constantly overshoots its slews, by 1/2 the offset, on
Serge> purpose. This maybe helps to get a more centered sawtooth when
Serge> repeatedly called by cron and the frequency is not
Serge> calibrated. Otherwise these 1/2 overshoots are rather disturbing.

Serge> Of course "ntpd -gq" doesn't overshoot so.

See http://bugs.ntp.isc.org/602 and be aware that it may not get fixed
because we are deprecating ntpdate in favor of sntp.


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