Detecting duplicate CIs

  • Release version: Washingtondc
  • Updated February 1, 2024
  • 1 minute to read

    • When the identification process encounters duplicate CIs, it groups each set of duplicate CIs into a de-duplication task for review and remediation. A large number of duplicate CIs might be due to weak identification rules. You can configure the identification engine to reconcile duplicate CIs.

    During CMDB Identification, processing of duplicate CIs is determined by the properties glide.identification_engine.skip_duplicates (set to true by default) and glide.identification_engine.skip_duplicates.threshold (set to 5 by default), and on the number of duplicate CIs that are detected. You can configure these properties so duplicate CIs are automatically reconciled, skipping duplication.

    • If glide.identification_engine.skip_duplicates is true, and the number of duplicate CIs is less than the threshold specified by glide.identification_engine.skip_duplicates.threshold, then the oldest of the duplicate CIs is picked as a match and gets updated. That oldest duplicate CI also becomes the main CI for that set of duplicate CIs. The rest of the duplicate CIs are tagged as duplicates by setting the cmdb_ci's duplicate_of to the appropriate main CI. During matching, the identification engine filters out any CI that is tagged as duplicate of any CI.
    • If glide.identification_engine.skip_duplicates is false, then matching of duplicate CIs fails with an error, and none of the duplicate CIs are updated.

    Also, the glide.duplicate_ci_remediator.max.cis property determines de-duplication processing for a large number of duplicate CIs. For more information, see the 'Large number of duplicate CIs' section in the Duplicate CIs remediation topic.

    In either case, de-duplication tasks are always created.

    Note:
    For a duplicate CI, if any of the CI's attributes, other than duplicate_of, is updated by IRE processing, then the CI is no longer considered a duplicate CI. In that situation, the value of duplicate_of is cleared in the CI.

    For more information about these properties, see Properties for Identification and Reconciliation.

    Review de-duplication tasks

    For information about reviewing and remediating de-duplicate tasks, and how the main CI is used, see Duplicate CIs remediation.