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Re: TS-7200: time sync issues
In message: <200812100356.mBA3uccU000394%ginger.cmf.nrl.navy.mil@localhost>
Ken Hornstein <kenh%cmf.nrl.navy.mil@localhost> writes:
: >What you are describing here is a frequency error. ntpd adjusts both
: >the phase of the clock, and its frequency. Usually the initial
: >inspection period is sufficient to get the initial estimate to within
: >a tens or hundreds of microseconds, and the frequency to with a ppm or
: >two (later it gets much better). This means in the 1000s that your
: >logs showed the clock should have drifted on the order of maybe 1ms.
: >Instead, it drifted by 200ms, 100x too much.
:
: Sigh. I don't know how to explain this any clearer.
:
: RIGHT AFTER the clock is stepped, ntpd reports the time being off ... by
: a lot (that's the 100-900ms I was talking about). During the 15 minutes
: or so that ntpd takes to reset itself, the this clock offset changes very
: little. I don't understand how that can be a frequency error. If it was
: a frequency error, it would never get in sync, but it does.
:
: Am I just not explaining this well?
The log that you posted showed 1000 deltas in time between the steps.
I've done a *LOT* of ntpd work with custom reflcocks and timing
hardware. Your problems look exactly like problems I've had with
systems that have frequency errors.
To get to the bottom of this:
o Turn off ntpd.
o Do an ntpdate.
o wait 10s
o Do an ntpdate.
What are the results?
Warner
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