CRON JOBS

Note:Set a cron job to run routine task automatically.

CRONTAB QUICK REFERENCE COMMANDS

crontab -e - Edit crontab

crontab - l : List crontab

crontab -r : Remove Crontab

crontab -l > xyz  : Backup Crontab to xyz

crontab xyz : Restore crontab from backup file xyz

#  Min    Hour  DayOfMonth  Month  Wkday  Command  # Comment

# (0-59) (0-23)   (1-31)    (1-12) (0-6)  (0=Sunday)

#

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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)

minute hour dom month dow user cmd

minute : This controls what minute of the hour the command will run on,   and is between '0' and '59'

hour :     This controls what hour the command will run on, and is specified in          the 24 hour clock, values must be between 0 and 23 (0 is midnight)

dom :     This is the Day of Month, that you want the command run on, e.g. to   run a command on the 19th of each month, the dom would be 19.

month :  This is the month a specified command will run on, it may be specified   numerically (0-12), or as the name of the month (e.g. May)

dow :     This is the Day of Week that you want a command to be run on, it can   also be numeric (0-7) or as the name of the day (e.g. sun).

user :     This is the user who runs the command.

cmd :     This is the command that you want run. This field may contain multiple words or spaces.