July 2024
Showing next 1000 cron schedules (Keep in mind some crons might be 'cut off' sooner than others depending on their frequency)
Showing next 1000 cron schedules (Keep in mind some crons might be 'cut off' sooner than others depending on their frequency)
When used infrequently, even one cron can be difficult to hold in your head. But multiple ones? Forget about it.
And why do we need multiple? Due to cron limitations in most Linux distros (Vixie cron), many common use cases require 2 or 3 separate cron jobs to schedule correctly.
This is the first tool that tries to tackle this problem and make it easier to manage multiple crons.
See some of the most common use cases that require multiple crons to get right (mostly).
Example 1
Run a cron at two different set times. For example, I want a cron to run twice daily, at 8:30am and 11:30pm.
This cannot be done with a single cron. You need two separate ones, like so:30 8 * * * command
30 23 * * * command
Example 2
Run a cron every 15 minutes throughout the day except at 3AM.
This cannot be done with a single cron. You need two separate ones, like so:*/15 0-2,4-23 * * * command
15-45/15 3 * * * command
Example 3
Run a cron at the last day of every month.
This cannot be done with a single cron. You need three separate ones, like so:0 0 30 4,6,9,11 * command
0 0 31 1,3,5,7,8,10,12 * command
0 0 28,29 2 * command
Note: this has a caveat. On leap years, it will run both on the 28th & 29th of February. Some cron implementations support the L modifier, which can be used to run a cron on the last day of the month. For example: 0 0 L * *.