[ntp:questions] Garmin GPS 18 LVC suddenly not syncing, leap?

unruh unruh at invalid.ca
Tue Nov 22 02:29:27 UTC 2011


On 2011-11-21, Pete Ashdown <pashdown at xmission.com> wrote:
> Dave Hart <davehart at gmail.com> writes:
>
>>PPS from the microseconds offset.  Which raises my favorite question:
>>which version of ntpd?  (ntpq -crv will say).  I'm guessing it's 4.2.4
>
> #ntpq -crv
> associd=0 status=c618 leap_alarm, sync_ntp, 1 event, no_sys_peer,
> version="ntpd 4.2.6p5-RC1 at 1.2330-o Mon Nov 21 16:46:05 UTC 2011 (1)"
>
>:(
>
>>> This is the Garmin section of my ntp.conf:
>>> ## LinuxPPS: GPS + PPS
>>> server 127.127.20.1 minpoll 4 prefer
>>> fudge 127.127.20.1 flag1 1 flag2 0 time2 0.600
>>>
>>> Still no dice. Help please?
>
>>The use of time2 0.600 and my guess of your version suggests you might
>>have used documentation not matching your version.  Steve Kostecke has
>>gathered and published a number of interesting versions of the NTP
>>docs at http://doc.ntp.org/ for easy reference.
>
> After more mucking around, I tried this config:
>
> server 127.127.20.1 mode 0 prefer
> fudge 127.127.20.1 flag1 1 flag2 0 time2 0.600
>
> I'm getting a >1000ms offset for the GPS vs offnet clocks:
>
>      remote           refid      st t when poll reach   delay   offset  jitter
>==============================================================================
>  ntp.mcast.net   .MCST.          16 u    -   64    0    0.000    0.000   0.000
> *GPS_NMEA(1)     .GPS.            0 l   49   64   17    0.000  -1083.0 629.393
>  time-C.timefreq .ACTS.           1 u   36   64   17   33.739  -106.33  71.426
>  india.colorado. .ACTS.           1 u   49   64    7   34.793  -77.157  49.965
>  ntp0.usno.navy. .USNO.           1 u   44   64   17  106.736  -88.392  66.800
>  ntp-nasa.arc.na .GPS.            1 u   40   64   17   19.771  -95.219  69.210

It sounds like you have the Garmin 18x, with an old firmware. UPGRADE.
It is known to be flakey. 


>
>
> Would it be advisable to do "time2 1.600" to compensate or is there a better
> way to do this?



More information about the questions mailing list