Cron Service

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Dragino supports cron service which you can schedule your task to be executed periodically.

Steps to use cron service

  • create file: /etc/crontabs/root
  • modify /etc/crontabs/root for scheduling task, below is the format and example
#run script /root/test at 10 every hour
#format [min] [hour] [day of month] [month] [day of week] [program to be run]
10 * * * * /bin/sh /root/test
  • restart cron service
root@dragino-1a7f76:~# /etc/init.d/cron restart

Explaination of the time format

Variable Range:

Variable Description
[min] Minutes that program should be executed on. 0-59. Do not set as * or the program will be run once a minute.
[hour] Hour that program should be executed on. 0-23. * for every hour.
[day of month] Day of the month that process should be executed on. 1-31. * for every day.
[month] Month that program whould be executed on. 1-12 * for every month.
[day of week] Day of the week. 0-6 where Sunday = 0, Monday = 1, ...., Saturday = 6. * for every day of the week.
[program] Program to be executed. Include full path information.

Use Operators:

Operator Function
Asterisk (*) Specifies all possible values for this field
Comma (,) Specifies a list of value for this field, for example, 1,5,6,8,10
Dash (-) Specifies a range of value for this field, for example: 1-5
Slash(/) Per , for example, */5, every 5 (minutes)


  • execute script at 8:30am every Monday To Friday
30 8 * * 1-5 /bin/test
  • execute script every 5 minutes
*/5 * * * * /bin/test