How to Reset Cron Time

Cron is a system tool used in various versions of the Unix and Linux operating systems. Cron allows the user to schedule processes and programs to run at certain times of the day, days of the week, or months of the year. If you've setup a cron program and decide that you need to reset it, either by changing the time, or deleting the task entirely, you can do this in a terminal window.

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Instructions

- 1
  
  Open up a terminal window. The exact steps for this will determine on your Linux/Unix operating system. In an Ubuntu Linux system running Gnome, for example, this can be done by going to "Applications Menu->Accessories->Terminal".
- 2
  
  Delete your cron by typing in the following command at the prompt (without the quotes):
  
  "crontab -r"
  
  This will delete your current cron file.
- 3
  
  Edit your crontab by typing in the following command;
  
  "crontab -e"
- 4
  
  Determine the time that you want to reset your cron. The crontab lists the commands in the following syntax:
  
  "02 05 2 3 4 /usr/local/bin/command"
  
  The numbers in the crontab file are identified as follows: the minutes (0-59), military time hours (0-23, 0 = midnight), day (1-31), month (1-12), weekday (0-6, with 0 = Sunday). You can use the "*" (no quotes) symbol to indicate the task is to run in every iteration of the cron. If the "*" symbol is used in the second slot, it means that task will run every hour on the designated day.
- 5
  
  Save the cron file within the text editor.