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Article View: comp.protocols.time.ntp
Article #742

Off by seconds? (xntpd)

#742
From: Bill Voss
Date: Tue, 16 Apr 1991 04:50
36 lines
2252 bytes
I just started running xntpd version 1.3 on my SparcStation last week.  
It runs as a stratum 3 client of the campus's three stratum 2 servers.  
Each of the campus's stratum 2 servers is peer with a different pair of 
off-campus stratum 1 servers, and also the other two campus servers.

At this instant, I have an
	xclock -digital -update 1
running on one of the ntp servers, and another on my local workstation.
To my vast surprise, the two xclock's disagree by roughly 15 seconds.
(Unfortunately I don't have accounts on the other two servers.)

Is this normal?  I expected them to agree to within a fraction
of a second, not disagree by 1/4 minute.

Would someone with accounts on multiple stratum 2 servers please
repeat my simple experiment? 

thanks,
Bill Voss <voss@cs.uiuc.edu> 

P.S.
The large delay is because I'm operating over a slip connection, but
even that delay is only a fraction of a second.

laslo$ ntpq -p ; xntpdc -s
     remote           refid      st  when poll reach  delay  offset   disp
==========================================================================
+uxc.cso.uiuc.ed 132.249.16.1     2  1011 1024  377   301.1   -8.47  446.2
+ux2.cso.uiuc.ed 192.43.244.9     2   521 1024  377   300.8    9.09    7.4
*garcon.cso.uiuc 128.8.10.1       2    11   64  377   301.5    4.33    5.8
     remote           local      st poll reach  delay   offset   disp
======================================================================
+ux2.cso.uiuc.ed 128.174.5.76     2 1024  377  0.3008  0.009090 0.0074
+uxc.cso.uiuc.ed 128.174.5.76     2 1024  377  0.3011 -0.008467 0.4462
*garcon.cso.uiuc 128.174.5.76     2   64  377  0.3015  0.004333 0.0058
laslo$ 
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From: voss@cs.uiuc.edu (Bill Voss)
Newsgroups: comp.protocols.time.ntp
Subject: Off by seconds? (xntpd)
Message-ID: <VOSS.91Apr16005051@laslo.cs.uiuc.edu>
Date: 16 Apr 91 04:50:51 GMT
Sender: news@m.cs.uiuc.edu (News Database (admin-Mike Schwager))
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Organization: Typed Smalltalk Group, Dept of Comp Sci, Univ of IL in Urbana.
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