[time] outlier

Kiss Gabor kissg
Thu Nov 2 10:59:12 UTC 2006


>> Could you explain me what the word 'outlyer' means in all NTP related
>> documents? Should I worry about remote servers marked with space in
>> output of "ntpq -p" or not?

> It's where one system is grossly different to all the rest.  Suppose that you 
> had 10 server.  Your offsets with 9 servers are in the range -0.1s to +0.1s, 
> but one server shows an offset of 0.9s.  It would be the "outlier" -

Look this:

      remote           refid      st t when poll reach   delay   offset  jitter
==============================================================================
*host1           .GPS.            1 u  202  256  377    0.553   -1.249   0.343
+host2           .GPS.            1 u  182  256  377    3.904   -0.879   0.073
-host3           xxx.xxx.xxx.xxx  2 u    9  256  377   33.926   -0.450   0.152
+host4           xxx.xxx.xxx.xxx  2 u    8  256  377   39.030   -1.050   0.252
-host5           xxx.xxx.xxx.xxx  2 u  202  256  377    0.564   -0.947   0.152

Host3 and host5 are marked as outliers.
Why?
Host4 has worse paremeters.

Gabor


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