hi,
I an CentOS 6.5,under /etc there is "cron.d" folder which contain system related jobs,I can also see "cron.daily" , "cron.houry" , "cron.monthly" and "cron.weekly" .
The thing which I want to understand is what are the purpose of these folders ?

Suppose I want that the system should daily shutdown automatically at 7:00 pm daily.I use the command

Using this my system shutdown successfully. The question is when this command is executed does it refer to or gives signals to "cron.daily" to do further work at back end side ?

In short I want to know the mechanism how cron works ,what are the purpose of "cron.daily" , "cron.houry" , "cron.monthly" and "cron.weekly" folders ? Does they also keep system related task aas well ?
thanks

The folders and the commands you add via crontab -e are not related. You can use the folders to conveniently run commands daily etc., but for full control of timing use the crontab command.

Yes, the cron.hourly, cron.daily, cron.weekly and cron.monthly are for automated system related tasks i.e logrotate, updating mlocate database etc. As stated they are unrelated to adding a users cron job via cron -e.

1 members found this post helpful.

thanks for your replies.