Crontab Linux Command details

Crontab command is a very important point of knowledge in Linux, for system administrators, with Crontab do timed cycle tasks can greatly improve work efficiency, before the scheduled cycle task, as a system administrator must first learn how to determine whether the Crond service is open.

Chkconfig--list | grep Crond

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Here the service is already open state, if said does not open, then executes the following command:

Service Crond start and then view:

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After confirming that the Crond service is turned on, it is possible to set up the cycle Timer task.

Setting crontab requires 5 * (* * * * * *), respectively, they represent the following meanings:

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The command to set the Loop Timer task is: CRONTAB-E

Example: Perform a restart command every two minutes

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After you save the exit, you can type crontab-l to view

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Where Crontab-r is the command to delete all the recurring timer tasks.

This article is from the "Brother Hong Linux World" blog, so be sure to keep this source http://zhengkangkang.blog.51cto.com/12015643/1859253

Crontab Linux Command details