[ntp:questions] To check tim

Danny Mayer mayer at ntp.isc.org
Fri Aug 31 19:46:56 UTC 2007

joachim.zobel at novartis.com wrote:
> Dear all,
> to synchronize time stamping in pharmaceutical enviromental it is possible 
> to connect all production machines via NTP to one Time Server.
> Question is: Is there a procedure developped to validate that all 
> connected production machines do have the same time adjusted than the time 
> server? This procedure must be initiated centralized e.g. on the Time 
> Server and not on the connected production machines to reduce the effort 
> for this test. 
> I tried to find a solution in the internet but without success.

If this is a production requirement, then I strongly suggest that you
invest in 4 refclocks and hook them up to 4 cheap or even older systems.
I suggest 4 since that way even if you lose one of them you still have
three left. There are plenty of products to choose from. Meinberg makes
excellent products if you want a European company, but there are plenty
of other companies.

Then configure ntp on each of your production systems to point to the
servers with the refclocks and after that your systems will stay in
synch for very long periods of time even if for some reason it loses
network connectivity for a while. It's a bad idea to have one single
Time Server since you cannot be sure that it won't die or lose
connectivity. Using 4 servers guaranteees that you have the reliability
that you need and will serve you much better and the production systems
will be synchronized to the same time (within milliseconds). Note that
you should do this for each physical location since remote systems
increase the amount of error in the accuracy of the time disciplined by ntp.

Refclocks and configurations are very cheap for a production environment
and well worth the payback. ntp uses almost no CPU cycles even when
bombarded with ntp queries.


> Thanks and Regards
> Dr. Joachim Zobel
> Global Pharma Engineering
> Novartis Pharma AG
> Novartis Pharma AG
> WRO 1241.102
> CH 4002 Basel, Switzerland
> Tel.: +41 616978311
> Fax: +41 61 6972435
> _______________________________________________
> questions mailing list
> questions at lists.ntp.org
> https://lists.ntp.org/mailman/listinfo/questions

More information about the questions mailing list