When does `cron.daily` run?

For the distributions you mention:

On CentOS 5.4 (Should be same for RHEL5)

grep run-parts /etc/crontab

01 * * * * root run-parts /etc/cron.hourly
02 4 * * * root run-parts /etc/cron.daily
22 4 * * 0 root run-parts /etc/cron.weekly
42 4 1 * * root run-parts /etc/cron.monthly

So cron.daily runs at 04:02am.

Same on CentOS 4.8

From the man page:

 Cron also searches for /etc/anacrontab

/etc/anacrontab in my system (Fedora 12) :

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

See also man anacrontab

For CentOS 6, you need to grep /etc/anacrontab and the answer varies if the server/laptop/dekstop/etc has been turned off or not.

cat /etc/anacrontab 
# /etc/anacrontab: configuration file for anacron

# See anacron(8) and anacrontab(5) for details.

SHELL=/bin/sh
PATH=/sbin:/bin:/usr/sbin:/usr/bin
MAILTO=root
# 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

So, between the hours of 3AM and 10PM** (after reboot and after the machine has been up for 5 minutes^^), run /etc/cron.daily. If there is no reboot, the job should run at 3:05AM++.

** As defined by START_HOURS_RANGE
^^ As defined by FIELD_TWO (i.e. the 5 after the 1 in the cron.daily line)
++ plus a random time between 0 and 45 minutes as defined by RANDOM_DELAY

Reference: http://linux.die.net/man/5/anacrontab

For SuSE systems (specifically SLES 11.1 and openSuSE 10.3) the daily run time of the /etc/cron.daily scripts is controlled by the value of the DAILY_TIME variable set in the /etc/sysconfig/cron file.

If the DAILY_TIME variable is not set, it defaults to: (time of last boot + 15 minutes).

On Ubuntu, you'll find a file /etc/crontab, from where this is configured. I guess it is something similar on RH and Centos.

CentOS6.x/RedHat6.x installs by default the package cronie-anacron. You have to:

yum install cronie-noanacron

yum erase cronie-anacron

Then you now have /etc/cron.d/dailyjobs to configure the best schedule time for your daily, weekly and monthly jobs.

I use Slackware (14.0), and did not have /etc/crontab. Also, anacron is not part of the distribution.

The solution on my system was as simple as running crontab -l as root:

root@flea:~# crontab -l
# If you don't want the output of a cron job mailed to you, you have to direct
# any output to /dev/null.  We'll do this here since these jobs should run
# properly on a newly installed system.  If a script fails, run-parts will
# mail a notice to root.
#
# Run the hourly, daily, weekly, and monthly cron jobs.
# Jobs that need different timing may be entered into the crontab as before,
# but most really don't need greater granularity than this.  If the exact
# times of the hourly, daily, weekly, and monthly cron jobs do not suit your
# needs, feel free to adjust them.
#
# Run hourly cron jobs at 47 minutes after the hour:
47 * * * * /usr/bin/run-parts /etc/cron.hourly 1> /dev/null
#
# Run daily cron jobs at 4:40 every day:
40 4 * * * /usr/bin/run-parts /etc/cron.daily 1> /dev/null
#
# Run weekly cron jobs at 4:30 on the first day of the week:
30 4 * * 0 /usr/bin/run-parts /etc/cron.weekly 1> /dev/null
#
# Run monthly cron jobs at 4:20 on the first day of the month:
20 4 1 * * /usr/bin/run-parts /etc/cron.monthly 1> /dev/null

From /etc/anacrontab on my Ubuntu 9.10 system:

1       5       cron.daily       nice run-parts --report /etc/cron.daily
7       10      cron.weekly      nice run-parts --report /etc/cron.weekly
@monthly        15      cron.monthly nice run-parts --report /etc/cron.monthly

There is no such facility as far as Solaris is concerned. Just use regular crontab entries for daily tasks.

OpenSuse 42.x Update :

/etc/crontab shows a file /usr/lib/cron/run-crons that is supposed to run every 15 minutes.

/usr/lib/cron/run-crons in turn ( has may lines of code ) which is looking for a variable called DAILY_TIME in /etc/sysconfig/cron

The file shows;

# At which time cron.daily should start. Default is 15 minutes after booting
# the system. Example setting would be "14:00".
# Due to the fact that cron script runs only every 15 minutes,
# it will only run on xx:00, xx:15, xx:30, xx:45, not at the accurate time
# you set.

DAILY_TIME=""

Set it to the time you need and restart cron via;

systemctl restart cron.service