[ntp:questions] setting the time/frequency before starting ntpd to avoid slow convergence (PPS)
gsricalde at gmail.com
Sat Oct 13 00:27:42 UTC 2012
On Saturday, October 13, 2012 7:25:26 AM UTC+8, Richard B. Gilbert wrote:
> On 10/12/2012 6:25 PM, gabs wrote:
> > 1. Kill ntpd if running
> To what purpose???????
> If NTPD is running, your clock should be very close to the correct time.
> I can't see anything useful to be gained by restarting NTPD.
For cases when ntpd is running and the offset and drift are way off. Your PPS measurements may be invalid while ntpd is running.
> Once you have your clock running, leave it running 24x365. An
> uninterruptable power supply is a good thing to have; it lets you ride
> out the brown outs and drop outs. Another good thing to have is a
> gasoline powered generator for those times when the power company really
> screws up! You should know BEFORE the power goes off what your
> emergency plan expects you to do..
This method is an option for setups not running 24x7 or environments where stable power is not available. You don't need hours to stabilize the NTP clock discipline, as long as the offset and frequency/drift is within acceptable bounds.
More information about the questions