[ntp:questions] Re: The classic "no server suitable for synchronization found" error on my ntpd server.

Richard B. Gilbert rgilbert88 at comcast.net
Fri Apr 28 16:45:01 UTC 2006


Mike wrote:

> I've removed all restrict statements, and the same thing is still
> occuring.  One thing I've looked at, that may help me widdle down this
> issue a little more, from a remote computer, I ran ntpd -ud <serverip>
> . In the output, I see "Server dropped: strata too high".
> 
> What would be causing my strata to be too high?  It is showing my
> stratum to be 16.
> 
> Thanks 
> 
> Mike
> 

"Stratum 16" means that the server is not synchronized!  It suggests 
that the server has lost contact with its own servers.

NTP is hierarchical!  At the top of the hierarchy are the atomic clocks 
at various national standards laboratories.  Stratum 1 servers get time 
directly from such an atomic clock.  The connection may be a few feet of 
cable or a radio broadcast from a GPS satellite; IOW it is one "hop" 
away from the atomic clock.

Stratum 2 servers get their time from stratum 1 servers.

Your stratum 16 server is getting its time from its wrist watch; it may 
or may not be correct but it has lost its place, or may not ever have 
had a place, in the hierarchy.

There are sites that, for one reason or another, do not or cannot have 
an internet connection and cannot or will not use a hardware reference 
clock such as a GPS receiver, WWV receiver, or WWVB receiver.  The 
latest version of ntpd supports an "orphan mode" that, as I understand 
it, will allow them to synchronize clocks but does not guarantee correct 
time.




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