How custom Cron schedule works in KACE SMA (4304980)

In Scripting, Patching and other KACE SMA features you can set how often a task runs under Schedule.

When setting a scheduled task it doesn't run on the exact expected time. 
When setting a scheduled task for an interval over an hour, it runs once an hour.

Cron on startup looks for files according to the crontab directories, then each crontab file found will determine the next time in the future each command is to be run. The commands set on the corresponding "five field" specifier will be reviewed by cron. 

Once it checks the files it will examine the task entry and compute how far in the future it is to be run, then sleep. Cron wakes up every minute, examining all stored crontabs, checking each command to see if it should be run in the current minute; then execute the task at the head of the queue and then determine the next time in the future to run this command and place it back on the event list.

In addition, if you set the value of minutes over 59, however it will NOT run at that interval and Will run once an hour.  Hour is also limited to a maximum setting of 23.  It can be set as XX minutes or XX hours.

This is working as designed.

Which cron the SMA uses?

The KACE SMA uses the native Cron scheduler to schedule tasks. Cron accepts these numbers from specific fields -

This is listed as "Custom Schedule" on different sections of the KACE SMA Admin Guide. 

Use the standard 5-field cron format (extended cron format is not supported):

* * * * *

| | | | |─ day of the week (0-6)(Sunday=0)

| | | |───── month (1-12)

| | |───────── day of the month (1-31)

| |───────────── hour (0-23)

|───────────────── minute (0-59)

As can be seen, valid entries for minutes is 0-59. Any value added over 59 will be set to the highest available number "59". As the input is 0-59, 59 is actually 60 minutes and will run once an hour.

Although the KACE SMA does not give an error when an invalid entry is made, it is dependent on the native Cron and will follow its format.

The native Cron feature is from FreeBSD (the OS the KACE SMA runs on). For more information on how FreeBSD Cron works please visit the documentation:

— FreeBSD crontab manual
 

Why KACE SMA cron doesn't run when planned?

It is important to note, FreeBSD cron is specific to the Operating System; not the same as other cron deployments. While 3rd party tools are helpful to understand custom schedule with cronjobs, they might not be aligned with the current cron schedules within the KACE SMA. Crontab.guru, Cronhub.io and other tools are not strictly identical to how KACE SMA interprets cronjobs.

These are the formats and values allowed for FreeBSD cron. 

	     field	   allowed values
	     -----	   --------------
	     minute	   0-59
	     hour	   0-23
	     day of month  1-31
	     month	   1-12	(or names, see below)
	     day of week   0-7 (0 or 7 is Sun, or use names)

Use the pre-built custom schedules