[ntp:questions] Re: HowTo calibrate system clock frequency using NTP

Daniel Kabs daniel.kabs at gmx.de
Mon Feb 6 11:09:00 UTC 2006

Good afternoon David,

I think we are talking at cross-purposes: in case of Plan B, you 
suggested to use the option "disable ntp" (so there should be no 
frequency correction) and to read the time offset at intervals using
    ntpq -c 'rv <assoc_id_of_peer>'

If I configure ntp that way, this is how the billboard looks on my 
system after some days of running time:

# ntpq -c 'rv 16532'
status=9634 reach, conf, sel_sys.peer, 3 events, event_reach,
srcadr=, srcport=123, dstadr=, dstport=123, keyid=0,
stratum=1, precision=-18, rootdelay=0.000, rootdispersion=6.989,
refid=DCFa, reftime=c7919b26.416249a1  Mon, Feb  6 2006 10:53:42.255,
delay=0.688, offset=-114389.792, jitter=75.264, dispersion=0.947,
reach=377, valid=7, hmode=3, pmode=4, hpoll=6, ppoll=6, leap=00,
flash=00 ok, org=c7919b4f.ed9e6256  Mon, Feb  6 2006 10:54:23.928,
rec=c7919bc2.517e5647  Mon, Feb  6 2006 10:56:18.318,
xmt=c7919bc2.514cec41  Mon, Feb  6 2006 10:56:18.317,
filtdelay= 0.69    0.68    0.77    0.79    0.88    0.77    0.69    0.69,
filtoffset= -114389 -114372 -114353 -114335 -114316 -114299 -114282 -114264,
filtdisp=  0.01    0.97    1.96    2.92    3.91    4.87    5.83    6.82

I was asking about reading the "offset" variable:
What is the corresponding time when this variable was set? The
billboard show several candidates ("reftime", "org", "rec" or "xmt"), 
but I don't know which one is the correct one.


David L. Mills wrote:
> Daniel,
> Your question does not parse. The frequency correction has nothing to do 
> with the state variables you quote. The time the frequency correction is 
> monitored is prominently displayed on the ntpq rv billboard.
> Dave
Refactor, don't archive! - SamHasler - 28 Aug 2004 - twiki.org

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