Re: ntpdate steps 86400 seconds

K.Dinh.P wrote:
"Tom Smith" <smith@xxxxxxxxxxxxxx> wrote in message news:433D2886.1030209@xxxxxxxxxxxxxxxxx

K.Dinh.P wrote:

"John Pettitt" <jpp@xxxxxxxxxxxxx> wrote in message

K.Dinh.P wrote:


I have a question concerning ntpdate. I synchronize to a timeserver using
crontab with ntpdate v4.1.1. The syslog is shown below:



[snip]

Why are you using ntpdate instead of ntpd?


Beacuse the precision with ntpd is too large on the single board hardware I´m using. 

I don't quite understand that.

However, you say you are synchronizing a time SERVER by running ntpdate.
Would that be a time server that is supplying time to other systems using
ntpd? It won't work, and the odd behavior you are seeing may well be
precisely because you are running ntpdate in the way you are.

-Tom


My test of ntpd show that the time synchronization diverge with a precision of no more than 200ms. This is due to the driver of the NAND flash disk I´m using. 

Sorry, I still don't understand, but never mind. After re-reading
your original post I see that this is only a time client, which,
I assume, has no serious requirements for time accuracy.

The time server is a windows machine with nettime installed. 

Here, no doubt, is your problem. Maybe nothing has changed on the server,
but that server has probably begun to display the weaknesses of this
approach. See http://nettime.sourceforge.net/ for a start.

All the evidence says that the server is changing the date forward
by one day as it crosses midnight and then changing it back 10
minutes later. Perhaps 10 minutes is nettime's update interval?
Or perhaps nettime is in turn using a server that has that problem?

If you install the reference implementation of NTP on that server
instead, you should get much better results. See
http://www.meinberg.de/english/sw/ntp.htm for the installer
provided by Meinberg.
.

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