Create a discovery schedule for an application CI

You can define how often Service Mapping runs the discovery process for different configuration items (CIs) and updates information about them.

Before you begin

If your ServiceNow instance uses domain separation and you have access to the global domain, select the domain to which the business service belongs from the domain picker ().

Make sure that at least one business service that the relevant CI is part of is in the operational state.

If your ServiceNow instance has domain separation enabled and you have access to the global domain, log in to the domain to which the business service belongs.

Role required: sm_admin or admin

About this task

When you define a new business service, Service Mapping performs discovery of all CIs that participate in this business service and creates its map. Service Mapping comes with a preconfigured generic schedule for discovering all CIs of the application type. CIs of the application type derive from the cmdb_ci_appl table. The generic schedule triggers the discovery of all applications in your organization once a day. In addition to the generic discovery schedule for applications, there is a preconfigured schedule for discovering load balancers deriving from the cmdb_ci_lb_service table. Typically, these two preconfigured schedules are enough to update information for business services.

Part of discovering an application CI is identifying its host. Service Mapping checks if the device hosting this application CI exists in CMDB. If not, Service Mapping triggers Discovery to perform host detection. The information on hosts is updated in CMDB when Discovery runs the horizontal discovery. You can manage schedules triggering the horizontal discovery as described in Create a Discovery schedule.

Some CI types are prone to more frequent changes and updates than others, so you can manage the load by adjusting the discovery schedule to match the nature of different CI types and avoid redundant stress on your infrastructure. For example, if you modify Apache Web server settings more often than updating your applications, therefore you may choose to create discovery schedules for Apache Web server that rediscover them more frequently than other CIs.

If necessary, you can create the following discovery schedules for application CIs:
  • For CI types

    Service Mapping discovers all CIs belonging to this type

  • For specific CIs

    Service Mapping discovers only one CI you specified for this schedule

When you define discovery schedules based on a CI type, several schedules may apply to the same CI. To avoid discovering the same CIs more than once the most specific schedule always takes precedence. For example, if there are two CI types one of which is a parent and the other is its child, and you create discovery schedules for both of them, CIs belonging to the child CI type are discovered only using the schedule for the child CI type, not the parent CI type. At the same time, if there is no schedule for a child CI type, the parent CI type schedule is used to discover a CI.

If you define a discovery schedule for a specific CI as well as a schedule for the CI type to which this CI belongs, Service Mapping uses the schedule for this specific CI, not a generic one for its CI type.

After Service Mapping discovers CIs belonging to your business service for the first time, it then runs discovery on CIs again to catch changes and updates. Discovery schedules determine what CIs and how often Service Mapping re-discovers.

Procedure

  1. In your ServiceNow user interface, navigate to Service Mapping > Administration > Discovery Schedules.
  2. To create a specific schedule, click New.
    Or

    To customize the generic schedule for all application CIs, click All Applications:

    The Discovery Schedule page opens.

    The Discovery Schedule page.
  3. Fill in the fields as follows:
    Table 1. Discovery Schedule Form for Service Mapping
    Field Description
    Name Enter a unique, descriptive name for your schedule.
    Discover Select Service for Service Mapping.
    MID Server Select the MID Server to use for this schedule. This field is available if Discover is set to Configuration items or Networks. If you select a MID Server, you cannot select a behavior for the schedule.
    Service discovery Select CI Type
    Note: In some special cases, you may want to create a schedule just for one specific CI. To do so, select Specific CI.
    CI type For a CI type-based schedule, select the relevant CI type from the list.
    CI For a specific CI-based schedule, select the relevant CI from the list.
    Active Select the check box to enable this schedule. If you clear the check box, the schedule is disabled, but you can still run a discovery manually from this form, using the configured values.
    Max Run Time Set a time limit for running this schedule. When the configured time elapses, the remaining tasks for the discovery are canceled, even if the scan is not complete. Use this field to limit system load to a desirable time window. If no value is entered in this field, this schedule runs until complete.
    Run Determines the run schedule of the discovery. Configure the frequency in the Run field and the other fields that appear to specify an exact time.
    Note: The run time always uses the system timezone. If you add the optional Run as timezone field, it has no effect on the actual runtime.
  4. Define when this schedule is run as follows:
    Table 2. Options for a Discovery Run Schedule
    Run option Description
    Daily Runs every day. Use the Time field to select the time of day this discovery runs.
    Weekly Runs on one designated day of each week. Use the Time field to select the time of day this discovery runs.
    Monthly Runs on one designated day of each month. Use the Day field to select the day of the month. Use the Time field to select the time of day this discovery runs. If the designated day does not occur in the month, the schedule does not run that month. For example, if you designate day 30, the schedule does not run in February.
    Periodically Runs every designated period of time. Use the Repeat Interval field to define the period of time in a days, hours, minutes and seconds. The first discovery runs at the point in time defined in the Starting field. The subsequent discoveries run after each Repeat Interval period passes.
    Once Run one time as designated by the date and time defined in the Starting field.
    On Demand Does not run on a schedule. Click the Discover now link to run this discovery.
    Weekdays Runs every Monday, Tuesday, Wednesday, Thursday, and Friday. Use the Time field to select the time of day.
    Weekends Runs every Saturday and Sunday. Use the Time field to select the time of day.
    Month Last Day Run the last day of every month. Use the Time field to select the time of day.
    Calendar Quarter End Runs on March 31, June 30, September 30, and December 31. Use the Time field to select the time of day. To change these dates, modify the script include DiscoveryScheduleRunType.
    After Discovery Allows you to sequentially stagger the schedule. Use this option to run this schedule after the Discovery designated in the Run after field finishes. Check the Even if canceled check box to designate that this discovery should run even if the Run after Discovery is canceled before it finishes.
    • This option is not valid when the Discovery is started via DiscoverNow, or when using the Discover CI feature.
    • You cannot designate an inactive Discovery schedule.
    • You cannot create a loop by designating the run after Discovery to be the same Discovery.
    • This Discovery does not run if the Run after discovery does not finish, with the exception that the Even if canceled box is checked and the Discovery is canceled.
  5. Click Submit.