How to create IRE rules to avoid duplicate CI creation ?

[B Ashok]

Hello Team, 

How to create IRE rules to avoid duplicate CI creation ?

I can see 3 CI created with same IP address, How Can we avoide creating duplicate CI ? Can you please some one help to create IRE rules to avoid duplicate CI creation.

Thanks

Ashok

[CMDB Whisperer]

I would assume you are actually using IRE for all of your data sources, but that would be the first thing to verify.  But even with IRE enabled out of box, duplicate IP addresses will not be interpreted as duplicate CIs.  For a variety of reasons, IP address on its own is not a good identifier of a device.  IP addresses can change.  A device can support multiple IP addresses.  An IP address can be common attributes to two configuration items that are components of a device.  So you should not assume a one-to-one relationship between an IP address and a CI.  That said, there is an identifier entry on the Hardware identifier defined for IP Address, but it is disabled out of box.  If you were to enable it then it is likely that this will result in a reduction of your Duplicate CIs.  The down side is that there could be unwanted results such as data collision, where one device CI is overwritten with another device's data, so I would strongly discourage enabling this identifier entry.