- It looks like editing /etc/yum/yum-cron.conf affects a *daily*
operation of yum-cron, whereas editing /etc/yum/yum-cron- hourly.conf provides hourly operations. The documentation is not very clear about this, and I'm a little confused here. In other words, yum-cron.conf affects /etc/cron.daily/0yum-daily.cron, and yum-cron-hourly.conf affects /etc/cron.hourly/0yum-hourly.cron.
Yes. All the cron scripts do is to execute yum-cron with an optional config script as an argument; if no config file is given, it uses the default (/etc/yum/yum-cron.conf). 'man yum-cron' tells you this.
I only really need yum-cron to run once a day, which would be sufficient.
The hourly version (in the default install) does nothing other than update the caches.
That being said, I can't figure out at what time it launches. All my users are in France, so ideally the daily yum-cron should be launched somewhere between 04:00 and 05:00 AM, since updating a package like httpd would restart the corresponding processes and kick online users out. I can't seem to figure out a way to define the exact time at which the daily yum-cron is being launched, since this doesn't seem to be controlled by standard crontab.
The scripts in /etc/cron.daily are run via anacron with a configuration file of /etc/anacrontab. The exact time the jobs are run are not specified and are variable depending on what the machine is doing (and a random delay). But you can impose time limits on when the jobs can be executed.
cron.hourly is different and executed via the normal cron system (config is in /etc/cron.d/0hourly)
P.