[CentOS] CentOS 4.5, kernel-2.6.9-55, NTPD trouble

Mon May 21 00:53:08 UTC 2007
Robert <kerplop at sbcglobal.net>

Following the update this morning, NTP is failing with the same symptoms 
that I saw several years ago (pre-CentOS, I believe) when Anaconda 
mistakenly blessed my ASUS A7N8X, Athlon (CPU: AMD Athlon(tm) XP 2600+ 
stepping 00) based system with an SMP kernel.  The symptom is that NTPD 
never establishes sync with a server, showing over the top jitter values.

[root at mavis log]# uname -r
2.6.9-55.EL
[root at mavis log]# ntpq -p
     remote           refid      st t when poll reach   delay   offset  
jitter
==============================================================================
 decimal.lib.ci. .STEP.          16 u   35   64    0    0.000    0.000 
4000.00
 dewey.lib.ci.ph 206.223.0.15     2 u   33   64   17   51.733  -725.97 
858.187
 clock.fmt.he.ne .GPS.            1 u   96   64   16  150.603  -1252.6 
996.045
 clock.sjc.he.ne .CDMA.           1 u   34   64   17   59.286  -70.022 
1301.68
 bigben.ucsd.edu .GPS.            1 u   30   64   17   96.343  -1280.8 
850.955
 ntp1.tummy.com  129.6.15.28      2 u   30   64   17   27.178  -1888.0 
1283.07
 ntp-0.gw.uiuc.e 128.174.38.133   2 u   29   64   17   38.694  -1324.4 
850.348
 ntp3.tamu.edu   128.194.254.7    2 u   27   64   17   16.334  -1328.6 
847.372
 ntp-1.cns.vt.ed 198.82.247.40    2 u   24   64   17   54.344  -777.83 
842.443
*LOCAL(0)        LOCAL(0)        10 l   26   64   17    0.000    0.000   
0.004
[root at mavis log]#             

So,  sometime around 4-5 minutes after starting ntpd, it had given up 
and synced with the local pseudo-source.
Rebooting into the previous kernel restores the operation this machine 
has enjoyed for the last couple years, quickly settling on an external 
source. (The following was copied after an extended period of time but 
the fact is that I have to really rush to boot, startx, open a root 
terminal and enter the commands before ntp stabilizes like this.)

[root at mavis log]# uname -r
2.6.9-42.0.10.EL
[root at mavis log]# ntpq -p
     remote           refid      st t when poll reach   delay   offset  
jitter
==============================================================================
 decimal.lib.ci. .STEP.          16 u  961 1024    0    0.000    0.000 
4000.00
-dewey.lib.ci.ph 198.153.152.52   2 u   45 1024  377   61.775   -9.729  
50.560
-clock.fmt.he.ne .GPS.            1 u   49 1024  375  144.312   40.998  
46.828
*clock.sjc.he.ne .CDMA.           1 u   96 1024  377   58.245    0.159   
0.468
-bigben.ucsd.edu .GPS.            1 u   33 1024  337   96.754   24.580   
0.351
-ntp1.tummy.com  129.6.15.28      2 u   36 1024  377   27.690    9.328   
1.335
+ntp-0.gw.uiuc.e 128.174.38.133   2 u   40 1024  377   39.836    1.047   
0.143
-ntp3.tamu.edu   128.194.254.7    2 u   88 1024  377   16.901    2.814   
0.005
+ntp-1.cns.vt.ed 198.82.247.40    2 u   94 1024  377   54.954    0.666   
0.069
 LOCAL(0)        LOCAL(0)        10 l   54   64  377    0.000    0.000   
0.004
[root at mavis log]#  


       
Has anyone else seen this behavior with kernel-2.6.9-55 ? 



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