Create blackout and maintenance schedules in Change Management

  • Release version: Australia
  • Updated March 12, 2026
  • 3 minutes to read

    • Use the Blackout and Maintenance windows to schedule a change. Blackout windows specify times during which normal change activity should not be scheduled. Maintenance windows specify times during which change requests should be scheduled. For example, create a blackout schedule for code freezes at the end of the year. blackout-maintenance-schedule

    Before you begin

    Role required: itil_admin or admin

    Ensure that the Change Management - Collision Detector (com.snc.change.collision) plugin is activated.

    About this task

    Conflict detection uses blackout and maintenance schedules to find potential scheduling conflicts for the configuration items (CIs) associated with a change request. When conflict detection runs, either automatically or by manual request, conflict detection determines if either type of defined schedule applies to the change request. If a potential conflict is identified, a warning message appears and conflicts are listed within the Conflict form section. View conflicts in the Conflict calendar.
    Note:
    To use the business service as the source for a blackout or maintenance schedule, the business service must be converted to an application service. For instructions, see Convert business services to application services. For information about application services, see Application services.

    Procedure

    1. Create a blackout or maintenance schedule.
      OptionDescription
      Create a blackout schedule
      1. Navigate to Change > Schedules > Blackout Schedules.
      2. Click New.
      Create a maintenance schedule
      1. Navigate to Change > Schedules > Maintenance Schedules.
      2. Click New.
    2. On the form, fill in the fields.
      Table 1. Blackout and Maintenance schedule form
      Field Description
      Name Unique name for the schedule.
      Description Short description about the schedule.
      Time zone Time zone for the schedule.

      Select Floating to evaluate planned start and end dates on the Change Request form for the logged-in user.
      Source Source of the blackout or maintenance schedule. The available options are Service, Change Request, and CI Class.
      Note:
      When you select Service or Change Request from the Source list, the Applies to field does not appear. The Applies to field appears if you select CI Class as the Source, which in turn enables the selection of a CI Class.
      Applies to CI classification that the conflict detection is filtered on.

      You can select a dynamic CI group so that all the configuration items in that dynamic CI group will be taken into account for blackout and maintenance when conflict detection is run.

      The dynamic CI group is seen as the parent CI to all the CIs that are within that group. If there are scheduling conflicts related to any of the CIs in the dynamic group, the conflict will be shown in the conflicts table of the dynamic CI group.
      Condition Conditions to specify the CIs that the schedule applies to.

      This field does not appear when the Applies to field is set to None.

      Note:
      Related fields used in conditions are not evaluated for blackout or maintenance schedules.
    3. Open the form context menu and click Save.
      A blackout or maintenance schedule is created and the Schedule Entries, Child Schedules, and Referenced By related lists appear in the change.
      Note:

      The Blackout Schedule [cmn_schedule_blackout] table extends the Condition Schedule [cmn_schedule_condition] table, which in turn extends the Schedule [cmn_schedule] table. The Blackout Schedule table inherits the domain properties from the Schedule table which has the Domain and Domain path columns.

      Because the Blackout schedule table uses the same Child Schedule and Schedule Entry tables as the Schedule table uses, the domain support is identical. The domain_master attribute is used to derive the domain from a parent record. For more information, see Domain support for schedules.

    4. Create one or more schedule entries by completing the following steps:
      1. In the Schedule Entries related list of the new maintenance schedule, click New.
      2. Enter a unique name and define the time during which you want to schedule the maintenance.
        For more information about the schedule entries field, see Schedule entry fields.
      Note:
      To delete the schedule created, select Delete. If you delete a schedule, the child schedules and schedule entries associated with the schedule would be deleted automatically.

    Result

    A blackout or maintenance schedule is created.

    What to do next

    Associate the configuration item with the maintenance schedule that is used in the change request.