When discovering a load balancer, duplicate serial number records are created in the cmdb_serial_number table.

When probes are used to discover the load balancer, each discovery of the load balancer creates a new serial number record that points to the CI. For example, discovering a load balancer five times will result in five duplicate serial number records.

If a horizontal discovery pattern used to discover the load balancer results in multiple input pages, then a serial number record is created for each page. For example, if the discovery results in five pages, then five duplicate serial number records are created and associated with the CI. Subsequent discoveries do NOT increase the count of serial number records. Discovering the load balancer again keeps the serial number record count at five and does not increase it to ten.

Steps to Reproduce


  1. Find a load balancer in the CMDB and check to see how many serial number records are associated with it.
  2. Discover the load balancer.
        After the Discovery, the number of serial number records associated with it will increment by 1.


  1. Discover a load balancer that results in multiple pages for the horizontal discovery pattern.
  2. After the discovery, check the number of serial number records associated with the CI.
        The number of serial number records associated with it is equal to the number of pages.


The workaround involves changing a condition on the Load Balancer identifier rule. 

WARNING: Applying this workaround causes two different load balancers that have the same serial number to reconcile as one load balancer. This happens for both probe and pattern Discovery.

For example: If the customer has load balancer A with serial number 123, and load balancer B with serial number 123, discovering both load balancers will cause them to reconcile as the same load balancer.

Steps to apply the workaround:

  1. Navigate to Configuration -> Identification/Reconciliation -> CI Identifiers.

  2. Open the Load Balancer record.

  3. In the Identifier Entries related list, open the entry record for the Serial Number [cmdb_serial_number] table.

  4. Right-click in the record header bar and select View -> Advanced.

  5. In the Optional condition condition builder, click the X to remove the Serial Number is BYPASS_THIS_RULE condition.

  6. Save the record.

  7. Delete the customer update records for your changes to allow automatic updates in the future to the cmdb_serial_number table.

    1. In the navigation search field, enter sys_update_xml.list and press Enter.

    2. In the list that appears, locate the update records for your changes.

      You can sort the updates by the most recent date or by the user who made the changes.

    3. Delete the records for the changes to the cmdb_serial_number table.

Effect on probe Discovery:

If you apply this workaround, rediscovering an existing load balancer does not create additional serial number records. However, any duplicate serial number records that were already created are not automatically cleaned up. If there were five serial number records associated with a load balancer before the workaround is applied, then after applying the workaround and rediscovering the load balancer, there will still be five serial number records associated with the load balancer.


Effect on pattern Discovery:

If you apply this workaround, discovering a load balancer that results in multiple pages with a horizontal discovery pattern associates one serial number record with the CI. After applying the workaround, duplicate serial number records are automatically cleaned up after the load balancer is rediscovered. After rediscovery, the duplicate serial number records associated with the load balancer are deleted, leaving only one serial number associated with the load balancer.

Related Problem: PRB1315162

Seen In


Intended Fix Version

New York

Fixed In

Madrid Patch 3

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Article Information

Last Updated:2019-05-21 11:41:49