[ntp:questions] Re: Synchronisation lost with swisstime.ethz.ch

mike michael.no.spam.cook at wanadoo.fr
Thu Aug 11 15:04:09 UTC 2005

frank.olsen at steria.com wrote:
> Thanks for your help!
> I did think that there was a problem with the server, but not knowing
> much about NTP I wasn't sure how to be absolutely sure. So, if I get a
> stratum 13 or 16 on a server that us supposed to be 1 or 2 or 3 or
> whatever, I can safely assume that there is something wrong with that
> server, is that correct?
> Another question: if I do use several servers, what happens if one of
> them doesn't respond? (OK, this is probably in the basic documentation
> so I'll read that right away.)
> Best regards,
> Frank Olsen
Yes, you should find all that you need in the doc.
Servers can change stratum, depending on their upstream servers stratum,
so the fact that they may change will have to be taken into account, 
however, big jumps would normally indicate either a problem , or maybe 
maint on that system. If you have sufficient servers defined , ntp will 
be able to isolate the bad guy and keep sync.
4 servers is really a minimum, as if you have only 3 and one dies, ntp 
is unable to tell which of the remaining 2 is trustworthy.

More information about the questions mailing list