Alauda Container Platform

Setting Scheduled Task Trigger Rules

The scheduled task trigger rules support the input of Crontab expressions.

TOC

Time Conversion

Time conversion rule: Local time - time zone offset = UTC

Taking Beijing time to UTC time as an example:

Beijing is in the East Eight Time Zone, with a time difference of 8 hours between Beijing time and UTC. The time conversion rule is:

Beijing Time - 8 = UTC

Example 1: Beijing time 9:42 converts to UTC time: 42 09 - 00 08 = 42 01, which means the UTC time is 1:42 AM.

Example 2: Beijing time 4:32 AM converts to UTC time: 32 04 - 00 08 = -68 03. If the result is negative, it indicates the previous day, requiring another conversion: -68 03 + 00 24 = 32 20, which means the UTC time is 8:32 PM of the previous day.

Writing Crontab Expressions

Basic format and value range of Crontab: minute hour day month weekday, with the corresponding value ranges as shown in the table below:

MinuteHourDayMonthWeekday
[0-59][0-23][1-31][1-12] or [JAN-DEC][0-6] or [SUN-SAT]

The special characters allowed in the minute hour day month weekday fields include:

  • ,: Value list separator, used to specify multiple values. For example: 1,2,5,7,8,9.
  • -: User-defined value range. For example: 2-4, which represents 2, 3, 4.
  • *: Represents the entire time period. For example, when used for minutes, it means every minute.
  • /: Used to specify the increment of values. For example: n/m indicates starting from n, increasing by m each time.

Conversion tool reference

Common Examples:

  • Input 30 18 25 12 * indicates a task triggers at 18:30:00 on December 25th.

  • Input 30 18 25 * 6 indicates a task triggers at 18:30:00 every Saturday.

  • Input 30 18 * * 6 indicates a task triggers at 18:30:00 on Saturdays.

  • Input * 18 * * * indicates a task triggers every minute starting from 18:00:00 (including 18:00:00).

  • Input 0 18 1,10,22 * * indicates a task triggers at 18:00:00 on the 1st, 10th, and 22nd of every month.

  • Input 0,30 18-23 * * * indicates a task triggers at 00 minutes and 30 minutes of each hour between 18:00 and 23:00 daily.

  • Input * */1 * * * indicates a task triggers every minute.

  • Input * 2-7/1 * * * indicates a task triggers every minute between 2 AM and 7 AM daily.

  • Input 0 11 4 * mon-wed indicates a task triggers at 11:00 AM on the 4th of every month and on every Monday to Wednesday.