Paul <[email protected]> wrote: > Not to suggest that someone is doing something unreasonable but again > why does time derived from the back-up clock need to be as accurate as > the local clock (say .5ms versus 2ms)? If there's a legitimate need > then trying to solve the problem with the wrong tool will only lead to > frustration and complaints that NTP is buggy.
One possible explanation is that people don't want their clock to suddenly track the changed offset in such cases. If only because ntpd will think that the frequency offset it has calculated over a long time period is suddenly wrong, and will change it to reflect a sudden time offset in a short time interval. It will then slew to the correct time, overshoot, and when the correct reference comes back online this will repeat in the other direction. This problem can partly be mitigated by ensuring that the offset between your local clock and the external references is as small as possible. (with some tweaking I can get these well below .5ms, often below .1ms) _______________________________________________ questions mailing list [email protected] http://lists.ntp.org/listinfo/questions
