[ntp:questions] Offset is always increasing

Riccardo Castellani ric.castellani at alice.it
Thu May 23 10:04:44 UTC 2013

You thought right, xntpd says "synchronisation lost" every 20 minutes, drift 
file is about 855, xntpd daemon is running from about 1 year.
In these days I 
made several days and I restarted daemon and I waited a day to analyze offset.

When I says "stable" I'm refering to value into drift file because I see always 
the same value, that is about 855.

Do you suggest me to measure specific drift 
of my hardware clock by script as documented into ntp.org, Known Hardware 
Issues, 9.1.6 (Mac Mini and other machines having poor TICK settings) ?
I test 
identical server (which has same problems) I delete the drift file and I 
restart daemon, after 2 hours :

ntpq -pn

     remote           refid      st 
t when poll reach   delay   offset    disp


*  2 u    9   64  377     0.61   -0.350    0.11     10 l    8   64  377     0.00    0.000   10.01

I'm worried because after many months I wouldn't like to find the same 
I have no other software to discipline time.

Riccardo Castellani 
>>>>>> I can see usually offset increases until 700 or
800 and it keeps

>>>>>> this value,

> It keeps this value means it's stable for many months, 
doesnt change

>>>>>> I thought you said xntpd reset it about every 20 
minutes. How can it
>>>>>> then have been stable for several months?

(If ntpd weren't correcting it, but only measuring it, I would suspect
that you had some other time discipline software that was doing a slow
adjustment to the clock and which thought the time was 700 to 800ms out.)

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