[CentOS] cron.hourly runs twice

Wed Mar 17 12:59:56 UTC 2010
Michael Schumacher <michael.schumacher at pamas.de>

Timothy,

On Wednesday, March 17, 2010 you wrote:

>>> For some reason I cannot fathom,
>>> cron.hourly runs twice each hour
>>> on one of my two CentOS-5.4 systems,

Here comes a very weird idea. I don't know the internals of the
cron-daemon good enough to know if this can actually happen.
If you have a NTP-job every hour started by cron that corrects the
internal time and if your internal clock runs too fast, the system
time may be reset every hour so that the cron-job will start twice. As
I said, I don't know if cron-daemon has a mechanism that would avoid
that problem.


best regards
---
Michael Schumacher
PAMAS Partikelmess- und Analysesysteme GmbH
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