anyone running GPS clocks in Southeastern Georgia?

Robert E. Seastrom rs at
Fri Jan 21 16:37:46 CST 2011

Gary Buhrmaster <gary.buhrmaster at> writes:

>> NTP isn't going to be the only "ripple".
> Most of the "brand name" GPS NTP solutions have a clock
> with is more than stable enough to survive without GPS
> lock for 45 minutes(*).  Some of the more expensive units with
> temperature controlled oscillators have hold times in the
> many weeks.  My guess is that the NTP ripples will be
> limited to those NTP servers just (or recently) booted
> which have not yet achieved a stable clock state.
> Gary
> (*) This presumes that this test results in loss of signal
>     lock, and not intentionally injected false information.

Seeing the ripples also presumes that people are monitoring their NTP
system health more closely than just looking at the output of ntpq -p.  :)


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