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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?


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