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Hello,
I have a question about dealing with SNTP sources.
when I interact with two SNTP servers (also named as NTP server),
then it's hard to find a solution to prevent the case of 'no majority'.
The most (S)NTP devices solved this problem with selecting of one
primary time source and one backup time source . More cannot be
adjusted.
I did it with following setting:
server <server-1-ip> iburst minpoll 6 maxpoll 8 prefered
server <server-2-ip> iburst minpoll 6 maxpoll 8 minstratum 8
The option 'prefered' didn't help, but lowering of stratum was
a solution to prevent the case of 'no majority'.
With following settings:
server <server-1-ip> iburst minpoll 6 maxpoll 8 prefered
server <server-2-ip> iburst minpoll 6 maxpoll 8
I got 'Can't synchronise: no majority' and here is my traces:
sources.c:324:(SRC_SetSelectable)[04-14:40:35] 10.126.9.246
sources.c:302:(SRC_AccumulateSample)[04-14:40:35] ip=[10.126.9.246] t=Wed
05/04/11 14:40:35.145764 ofs=-0.003653 del=0.000741 disp=0.000629 str=2
sourcestats.c:574:(SST_GetSelectionData)[04-14:40:35] n=4 off=0.000498
del=0.000897 dis=0.001328 var=0.000000 pdist=0.001318 avoff=-0.000005
avok=1 selok=1
sourcestats.c:574:(SST_GetSelectionData)[04-14:40:35] n=4 off=-0.003653
del=0.000741 dis=0.000632 var=0.000000 pdist=0.001000 avoff=-0.004032
avok=1 selok=1
sources.c:624:(SRC_SelectSource)[04-14:40:35] Can't synchronise: no
majority
210 Number of sources = 2
MS Name/IP address Stratum Poll LastRx Last sample
=================================================================
^x 10.126.9.245 2 6 33 +20ns[-1669us] +/- 398us
^x 10.126.9.246 2 6 33 -4332us[-4332us] +/- 857us
After a while is again synchronized
210 Number of sources = 2
MS Name/IP address Stratum Poll LastRx Last sample
===============================================================
^* 10.126.9.245 2 6 50 -111us[ -278us] +/- 378us
^+ 10.126.9.246 2 6 49 +737us[ +737us] +/- 521us
After 2..3 min again: Can't synchronise: no majority
210 Number of sources = 2
MS Name/IP address Stratum Poll LastRx Last sample
================================================================
^x 10.126.9.245 2 6 4 -403us[ -403us] +/- 529us
^x 10.126.9.246 2 6 2 +2207us[+2207us] +/- 353us
and so on
=======================================================================
Date (UTC) Time IP Address St Freq ppm Skew ppm Offset
=======================================================================
2011-05-04 14:40:28 0.0.0.0 0 19.521 42.166 0.000e+00
2011-05-04 14:40:33 10.126.9.246 3 19.521 42.166 -2.127e-03
2011-05-04 14:40:34 10.126.9.245 3 19.521 42.166 4.087e-03
2011-05-04 14:40:35 0.0.0.0 0 19.521 42.166 0.000e+00
2011-05-04 14:41:39 10.126.9.245 3 -0.505 50.104 -1.669e-03
2011-05-04 14:41:40 0.0.0.0 0 -0.505 50.104 0.000e+00
2011-05-04 14:42:43 10.126.9.245 3 -9.630 15.559 -8.059e-04
2011-05-04 14:42:45 0.0.0.0 0 -9.630 15.559 0.000e+00
2011-05-04 14:43:49 10.126.9.245 3 -11.892 9.416 -3.936e-04
2011-05-04 14:44:53 10.126.9.245 3 -12.749 5.457 -1.671e-04
2011-05-04 14:45:57 0.0.0.0 0 -12.749 5.457 0.000e+00
2011-05-04 14:49:11 10.126.9.246 3 -12.434 8.937 5.796e-03
2011-05-04 14:50:16 10.126.9.246 3 -11.686 15.050 6.131e-04
2011-05-04 14:51:19 10.126.9.245 3 -1.017 27.162 1.354e-04
2011-05-04 14:52:20 0.0.0.0 0 -1.017 27.162 0.000e+00
2011-05-04 14:52:25 10.126.9.245 3 -1.017 27.162 2.711e-04
The solution 'minstratum 8' is fine for me. The behavior
without setting of minstratum was unclear for me.
Is it explainable?
Nice greetings,
Harald
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