Shulou(Shulou.com)06/01 Report--

This article will explain in detail about the CentOS system installation crontab process is how, the content of the article is of high quality, so the editor to share with you to do a reference, I hope you have a certain understanding of the relevant knowledge after reading this article.

Crontab commands are common in Unix and Unix-like operating systems and are used to set instructions that are executed periodically. This command reads instructions from a standard input device and stores them in a "crontab" file for later reading and execution. Typically, instructions stored in crontab are activated by daemons, and crond is often run in the background, checking every minute to see if there are scheduled jobs to be executed. This type of assignment is commonly referred to as cron jobs. Here, I'm going to show you how to install crontab on a CentOS system.

CentOS system installation crontab:

[root@CentOS ~] # yum install vixie-cron

[root@CentOS ~] # yum install crontabs

Description:

Vixie-cron package is the main program of cron

The crontabs package is a program that installs, uninstalls, or enumerates tables used to drive cron daemons.

Cron is a built-in service for linux, but it does not start automatically. You can start and shut down this service in the following ways:

/ sbin/service crond start / / start the service

/ sbin/service crond stop / / shut down the service

/ sbin/service crond restart / / restart the service

/ sbin/service crond reload / / reload the configuration

View crontab service status: service crond status

Start the crontab service manually: service crond start

To see if the crontab service is set to boot, execute the command: ntsysv

Add boot to CentOS system and start automatically: chkconfig-- level 35 crond on

CentOS system crontab command

Function description: set timer.

Syntax: crontab [- u] [configuration file] or crontab [- u] [- elr]

Note: cron is a resident service that provides timer functions that allow users to execute preset instructions or programs at a specific time. As long as the user can edit the configuration file of the timer, the function of the timer can be used. The configuration file format is as follows: Minute Hour Day Month DayOFWeek Command

Parameters:

-e edit the timer settings for the user.

-l lists the timer settings for the user.

-r removes the timer setting for the user.

-u specifies the name of the user to set the timer.

On the CentOS system installation crontab process is how to share here, I hope the above content can be of some help to you, can learn more knowledge. If you think the article is good, you can share it for more people to see.

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.