Detailed description of crontab command format and summary of common writing methods

Catalog

Format specification

Summary of common writing methods

Execute every minute

Every time 10 Once per minute

Every time 2 Once per hour

At the end of every hour 15 Minute execution

At the end of every hour 15 minute 、 The first 30 Once per minute

Every day 7:00 to 9:00 Between , every other 10 Once per minute

Every day 6:35 perform

Every day 7:08,8:08,10:08 perform

Every morning from Monday to Friday 6:35 perform

Saturday 、 Sunday morning 6:35 perform

Saturday 、 Every Sunday 3 Once per hour

monthly 1 Morning in the morning 6:30 perform

monthly 1 Number 、5 Number 、15 Number 、 morning 6:30 perform

monthly 5 Morning in the morning 6:30 And every Saturday morning 6:30 perform

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Format specification

*　　*　　*　　*　　*　　cmd
branch 　 when 　  Japan 　  month 　  Zhou 　    command

The first 1 Column ： minute 1-59 Per minute * perhaps */1 Express
The first 2 Column ： Hours 1-23（0 Express 0 spot , 10 Express 10 spot ,20-6 It means from eight o'clock in the evening to the next day 6 During the hour ）
The first 3 Column ： date 1-31（7 Means every month 7 Japan ,7,8,15 Means every month 7 Japan 、8 Japan 、15 Japan ）
The first 4 Column ： month 1-12
The first 5 Column ： What day , Optional range 0-6（0 Sunday ,1 For Monday ,6 For Saturday ）
The first 6 Column ： Running commands

namely ：
*： Anytime , For example, in the minute position, it means every minute , In the hour position, it means every hour
Comma concatenation ： Custom moments
Center dash splicing ： A continuous period of time
Slash ： Said every , Such as minute position */60 It means every 60 minute

Summary of common writing methods

Such as , The scheduled task to be performed is to perform /a/b/c.sh Script , Perform log writing /var/log/c_cron.log file .

Execute every minute

*  *  * * *    root   /a/b/c.sh  >> /var/log/c_cron.log &

Every time 10 Once per minute

*/10 *  * * *    root   /a/b/c.sh  >> /var/log/c_cron.log &

Every time 2 Once per hour

* */2  * * *    root   /a/b/c.sh  >> /var/log/c_cron.log &

At the end of every hour 15 Minute execution

15 */1 * * *    root   /a/b/c.sh  >> /var/log/c_cron.log &

At the end of every hour 15 minute 、 The first 30 Once per minute

15,30 */1 * * *    root   /a/b/c.sh  >> /var/log/c_cron.log &

Every day 7:00 to 9:00 Between , every other 10 Once per minute

/10 7-9 * * *    root   /a/b/c.sh  >> /var/log/c_cron.log &

Every day 6:35 perform

35 6 * * *    root   /a/b/c.sh  >> /var/log/c_cron.log &

Every day 7:08,8:08,10:08 perform

8  7,8,10 * * *    root   /a/b/c.sh  >> /var/log/c_cron.log &

Every morning from Monday to Friday 6:35 perform

35 6 * * 1,2,3,4,5    root   /a/b/c.sh  > /var/log/c_cron.log &
 or 
35 6 * * 1-5    root   /a/b/c.sh  > /var/log/c_cron.log &

Saturday 、 Sunday morning 6:35 perform

35 6 * * 6,0   root   /a/b/c.sh  > /var/log/c_cron.log &

Saturday 、 Every Sunday 3 Once per hour

* /3 * * 6,0   root   /a/b/c.sh  > /var/log/c_cron.log &

monthly 1 Morning in the morning 6:30 perform

30 6 1 * *    root   /a/b/c.sh  > /var/log/c_cron.log &

monthly 1 Number 、5 Number 、15 Number 、 morning 6:30 perform

30  6  1,5,15  * *    root   /a/b/c.sh  > /var/log/c_cron.log &

monthly 5 Morning in the morning 6:30 And every Saturday morning 6:30 perform

30 6 5 * 6    root   /a/b/c.sh  > /var/log/c_cron.log &