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@mavis log]# uname -r
2.6.9-55.EL
[root@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@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@mavis log]# uname -r
2.6.9-42.0.10.EL
[root@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@mavis log]#
Has anyone else seen this behavior with kernel-2.6.9-55 ?
--
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