This tutorial demonstrates how to schedule S3 backups with cron expressions.

Overview

Currently, you are allowed to schedule S3 backups with cron expressions. You need to configure the backupSchedule property under the spec field in the YAML configuration file of the cluster, for example:

... 
spec:
  replicas: 3
  mysqlVersion: "5.7"
  backupSchedule: "0 0 0 * * *"  # daily
  ...

Backup scheduling

Cron expression format

A cron expression represents a set of times, using 6 space-separated fields in the format of [second] [minute] [hour] [day] [month] [day of week].

Note:

Month and Day-of-week field values are case-insensitive. SUN, Sun, and sun are equally accepted.

Special characters

Asterisk ( * )

The asterisk indicates that the cron expression will match for all values of the field. For example, using an asterisk in the 5th field (month) would indicate every month.

Slash ( / )

Slashes are used to describe increments of ranges. For example 3-59/15 in the 1st field (minutes) would indicate the 3rd minute of the hour and every 15 minutes thereafter. The form *\/... is equivalent to the form first-last/..., that is, an increment over the largest possible range of the field. The form N/... is accepted as meaning N-MAX/..., that is, starting at N, use the increment until the end of that specific range. It does not wrap around.

Comma ( , )

Commas are used to separate items of a list. For example, using MON,WED,FRI in the 5th field (day of week) would mean Mondays, Wednesdays and Fridays.

Hyphen ( - )

Hyphens are used to define ranges. For example, 9-17 would indicate every hour between 9am and 5pm inclusive.

Question mark ( ? )

Question mark may be used instead of * for leaving either day-of-month or day-of-week blank.

Predefined schedules

You may use one of several pre-defined schedules in place of a cron expression.