Linux Scheduled Tasks crontab

System timed Tasks

Croond service Management and access control

Systemctl Start Crond.service Open Crond Service

Crontab-e into Crontab Edit interface

* * * * * * tasks performed

The first "*" Hour of the second minute 0-59

The second "*" the first hour of the day 0-23

The third "*" one months of the first day 1-31

Fourth "*" months of the year 1-12

Fifth "*" a week of the week 0-7 (0 and 7 are both represented Sunday)

* represents any time. If the first "*" represents a single execution per minute

, which represents a discontinuous time, such as 0 8,12,16 * * * represents the execution of a command at 8, 12, and 16 points per day.

-Represents a continuous time range. such as 0 5 * * 1-6 for Monday to Saturday of the 5-point execution order

The */n represents how often it is executed every once in a while. such as */10 * * * * represents every 10 minutes

In crontab "%" has special meaning, need to add \ escape character

Linux Scheduled Tasks crontab