[ntp:questions] Ntp looses sync

Heiko Gerstung heiko.removethistext.gerstung at meinberg.de
Thu Apr 2 07:16:41 UTC 2009

Towli schrieb:
> Hello all
> We're testing a DCF77 appliance box (EMC professional from 
> www.gude.info), which every now and the looses its connection to the 
> DCF77 signal and switches over to quartz mode. Upon doing this, our test 
> switch looses its sync to it, and considers it a stratum 11 server 
> instead of a stratum 1. The switch also has configured an "ordinary" 
> stratum 5 windows-server, and it seems to me that it uses this one, when 
> the appliance box is seen as being stratum 11 (and syslog says the 
> switch lost ntp-sync to the stratum 11 appliance box, but syncs back 
> when the DCF77 signal is restored).
> Will a switch allways use the lower stratum server? Can i stop the 
> switch from synching with other servers (when the dcf box looses its 
> signal and runs in the otherwise reliable quarts-mode), while still 
> having a backup ntp server configured in case the appliance bos goes 
> down?  Is a constant sync important or is it ok for the switch to synch 
> with different servers 'along the way'?
> I thank you all for your kindness so far.

Hi Towli,

I know NTP appliances that allow you to configure the stratum level of 
the unit when it is in holdover/free running mode. There is a good 
chance that the Gude box allows for the same. Did you check that with 
their technical support?


More information about the questions mailing list