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*     *     *   *    *        command to be executed
-     -     -   -    -
|     |     |   |    |
|     |     |   |    +----- day of week (0 - 6) (Sunday=0)
|     |     |   +------- month (1 - 12)
|     |     +--------- day of        month (1 - 31)
|     +----------- hour (0 - 23)
+------------- min (0 - 59)

crontab -l

crontab -u username -lExample with user testuser:

crontab -u testuser -l

First view all the daily cron jobs:

ls -la /etc/cron.daily/

Then view a specific daily cron job:

less /etc/cron.daily/filename

Example with filename logrotate:

less /etc/cron.daily/logrotate

First view all the hourly cron jobs:

ls -la /etc/cron.hourly/

Then view a specific hourly cron job:

less /etc/cron.hourly/filename

Example with filename 0anacron:

less /etc/cron.hourly/0anacron

First view all the weekly cron jobs:

ls -la /etc/cron.weekly/

Then view a specific weekly cron job:

less /etc/cron.weekly/filename

Example with filename weeklyexample:

less /etc/cron.weekly/weeklyexample

First view all the monthly cron jobs:

ls -la /etc/cron.monthly/

Then view a specific monthly cron job:

less /etc/cron.monthly/filename

Example with filename readahead-monthly.cron:

less /etc/cron.monthly/readahead-monthly.cron

less /etc/crontab