I have a small perl script I use to keep the boxes up to date.
Here is the script:
$si = $ARGV;
@ooo = `yum -y update`;
print Y @ooo;
$ss = 'yum output from ' . $si;
$sss = "mail -s \"$ss\" address\@email.com < yum.out";
This will create a file called yum.out and email it to you. I like to know what is being updated, specially when it's a kernel update.
then I set cron to run it using the name of the machine as a argument:
10 3 * * * /root/scripts/yum.cron.pl Hostname