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4.13. Cron

Vixie cron and Cronie
Red Hat Enterprise Linux 6 includes the cronie package as a replacement for vixie-cron. The main difference between these packages is how the regular jobs (daily, weekly, monthly) are done. Cronie uses the /etc/anacrontab file, which by default looks like the following:
# the maximal random delay added to the base delay of the jobs
RANDOM_DELAY=45

# the jobs will be started during the following hours only
START_HOURS_RANGE=3-22

# period in days   delay in minutes   job-identifier   			command

1			5		cron.daily	nice run-parts	/etc/cron.daily
7			25		cron.weekly	nice run-parts	/etc/cron.weekly
@monthly		45		cron.monthly	nice run-parts	/etc/cron.monthly
These regular jobs will be executed once a day in the 03:00-22:00 time interval, including a random delay. For example, cron.daily will have a 5 minute forced delay plus a random delay of 0-45 minutes. You could also run jobs with no delays, between 4 and 5:
RANDOM_DELAY=0 # or don't use this option at all

START_HOURS_RANGE=4-5

# period in days   delay in minutes   job-identifier   			command
1			0		cron.daily	nice run-parts	/etc/cron.daily
7			0		cron.weekly	nice run-parts	/etc/cron.weekly
@monthly		0		cron.monthly	nice run-parts	/etc/cron.monthly
Features of cronie include:
For further details about cronie and cronie-anacron, please refer to the Red Hat Enterprise Linux Deployment Guide.