How to avoid duplicate Ci creation

[saranyavs]

Hi team,

In CMDB there is one CI which has  created under three different classes. with same name, same IP address and same serial number. Is this duplicate CIs ,created because of identification rule? how to avoid this in future?

a. Storage Switch
b. Storage device
c. Storage Server

Regards,

Saranya

[Dominik Simunek]

Hi Saranya,

It is hard to identify the root cause of duplicate CIs without digging into the instance and the sources. IRE should help to avoid duplicates. Question then is: a) How were those CIs created? What are their Discovery sources? b) Was IRE used when creating the CIs as that is the best practice for every automatic import/discovery? c) If you are sure that IRE was used, review the config of Identification Rules for the 3 CI classes.

[vaishali231]

hey @saranyavs 

If you have CIs with the same Name, IP address, and Serial Number but created under three different classes (Storage Switch, Storage Device, Storage Server), this behavior is usually related to how the Identification and Reconciliation Engine (IRE) works.

Why this happens

Identification rules are evaluated per class. Even if the attribute values are identical, IRE will not match records across different classes. If incoming data is classified differently (for example, by Discovery or an integration), the system can create separate CIs in each class.

Common causes include:

Different identification rules configured for each class

Weak identification criteria (e.g., not consistently using Serial Number)

Inconsistent classification from Discovery or external integrations

Missing or misconfigured reclassification logic

From a CMDB perspective, these are not considered duplicates automatically because they exist in different classes, but functionally they may represent the same device.

How to prevent this in the future

Review Identification Rules
Navigate to Identification Rules and ensure strong identifiers (such as Serial Number + Manufacturer) are consistently configured for related classes.

Validate Classification Logic
If Discovery or an integration is involved, review how the device is being classified and ensure it maps consistently to the correct class.

Strengthen Identification Criteria
Avoid relying only on Name or IP address, as these can change. Serial Number is generally a stronger identifier.

Review Identification Logs
Check Identification Logs to understand why IRE created a new CI instead of matching an existing one

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If this response helps, please mark it as Accept as Solution and Helpful.

Doing so helps others in the community and encourages me to keep contributing.

Regards,

Vaishali Singh