Administer > Scheduled maintenance > Scheduled Maintenance exception models

Scheduled Maintenance exception models

Scheduled Maintenance includes a system of exception models that enables an administrator to schedule tasks around weekends or holidays. You can choose one of these models:

Model Restrictions
No Exceptions model Scheduled Maintenance tasks run whenever they are scheduled, regardless of weekends or holidays. After the task runs, it immediately reschedules for the next occurrence. For example, the task runs every hour on the half hour at 8:30 AM, 9:30, 10:30, ... 5:30 PM and so on.
Only Calendars model Scheduled Maintenance tasks run only if the assigned time occurs within a specific calendar. For example, a task scheduled to run only during the day shift (9:00AM - 5:00PM) can run at 2:00 PM, but not at 7:00 PM.
Except Calendars model Scheduled Maintenance tasks run according to schedule unless the designated time falls within a specific calendar. For example, a task scheduled to run at any time, except during the day shift, cannot run between 9:00AM and 5:00PM, but can run at all other times.

Exceptions do not stop a task from recalculating normally, but if its scheduled time falls within an exception window, the task does not run. Scheduled Maintenance displays a message in the task history log to indicate that the task triggered, but did not run because it occurred during an exception window.

Notes:

  • Exceptions apply only to calendar-based tasks. They do not apply to demand-based maintenance tasks.
  • Exceptions apply to any type of scheduled task. Tasks with weekly, monthly, or yearly schedules can use exception calendars. As a practical matter, they're probably most useful for tasks with simple recurrence schedules, but the system will support their use with any schedule you set up.
  • All tasks default to the No Exceptions model.
  • Tasks which expire and attempt to run during an exception window do not "push" to the next available acceptable execution time. They simply do nothing and reschedule.

Examples: Scheduled Maintenance exception models

Assume that you have a Day Shift calendar that specifies 9AM – 5PM, Monday – Friday. Saturday and Sunday are not included in the calendar. There is a scheduled task that runs every hour beginning at 8:30 AM.

Model Result
No Exceptions model The task runs every hour on the half-hour 8:30 AM, 9:30, 10:30, ... 5:30 PM and so on.
Only Calendars model The task runs only during the Day Shift. The task runs every hour on the half-hour 8:30 AM, 9:30, 10:30, … 4:30 PM. The task triggers again at 5:30 PM, but does not run because it cannot run outside of the defined calendar hours.
Except Calendars model The task run at any time except during the Day Shift. The task triggers at 8:30 AM, 9:30, 10:30, … 4:30 PM, but it does not run until the Day Shift ends. When the task triggers at 5:30 PM, it runs normally.