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Schedule a top-down discovery by Service Mapping

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Schedule a top-down discovery by Service Mapping

After Service Mapping discovers CIs belonging to your application service for the first time, it then runs discovery on CIs again to find changes and updates. You can define how often Service Mapping runs the discovery process for different configuration items (CIs) and updates information about them.

Before you begin

Define your application services prior to defining discovery schedules for discovering CIs which are part of these services.

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

Role required: sm_admin

About this task

When you define a new application service, Service Mapping performs discovery of all CIs that participate in this application service and creates its map. After the initial mapping is complete, Service Mapping regenerates application service maps regularly by rediscovering CIs making up a application service.

In the base system, Service Mapping is preconfigured with these generic schedules:
All Applications
This schedule triggers the top-down discovery of all CIs of the application type [cmdb_ci_appl].
Load Balancer Service
This schedule starts the top-down discovery of all CIs of the load balancer service type [cmdb_ci_lb_service]
The generic schedules trigger discovery of all applications and load balancer services in your organization once a day. Typically, these two preconfigured schedules are enough to update information for application services.
Part of discovering an application CI is identifying its host. Service Mapping checks if the device hosting this application CI exists in the CMDB. For a load balancer service, Service Mapping checks if the load balancing device hosting this load balancer service exists in the CMDB. If not, Service Mapping triggers Discovery to perform the horizontal discovery. As a result, Discovery performs host detection and updates the information on hosts in the CMDB. If necessary, you can manage the schedules that trigger horizontal discovery as described in:

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 each CI type. Having customized discovery schedules also allows you to avoid redundant stress on your infrastructure. For example, if you modify Apache Web server settings more often than updating your applications, 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 that you specified for this schedule

When you define discovery schedules based on CI types, several schedules may apply to the same CI. To avoid discovering the same CIs more than once the most specific schedule always has precedence. For example, if you create separate discovery schedules for a parent CI type and its child CI type, CIs belonging to the child CI type are discovered using its dedicated schedule. At the same time, if there is no schedule for a child CI type, the parent CI type schedule is used to discover the child CIs.

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, and not the generic schedule for its CI type.

Procedure

  1. Navigate to Service Mapping > Administration > Discovery Schedules.
  2. To create a schedule for a specific CI or CI type, click New.
    Or

    To customize the generic schedule for all application CIs, click All Applications or Load Balancer Service.

    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 For a new specific schedule, enter a unique and descriptive name.
    Discover For a new specific schedule, select Service for Service Mapping.
    Service discovery For a new specific schedule, select CI Type.
    Note: In some special cases, you can create a schedule just for one specific CI. To do so, select Specific CI.
    CI type For a new CI type-based schedule, select the relevant CI type from the list.
    CI For a new schedule for a specific CI, 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 and related fields 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 time zone. If you add the optional Run as tz field, it has no effect on the actual runtime.
  4. Define the schedule:
    Table 2. Discovery schedule run options
    Run option Description
    Daily Runs every day. Use the Time field to specify the time of day.
    Weekly Runs on one designated day of each week. Use the Time field to specify the time of day.
    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 specify the time of day. 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 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 Discover now to run 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 the dates, modify the DiscoveryScheduleRunType script include.
    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. Select 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 check box is selected and the Discovery is canceled.
  5. Click Submit.
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