How does discovery match a discovered CI with a record in the CMDB?

[HugoFirst]

Our situation is this.

I have a user who is entering ASSET records manually and a CI is created for each ASSET record.

Let's say it's for a system named LapTop1.   Initially, LapTop1 is placed in a storeroom, but eventually it is assigned to a person.

The new system LapTop1 is configured, software installed and it is placed on the network where it is discovered.

Only the result of the discovery is a new CI record ( _not_ the one created when the Asset record was created ), and a second ASSET record is created which is linked to the new CI record.   In other words, duplicate records are created.

The ideal situation would be for Discovery to find the CI record which already exists in the CMDB ( from when the ASSET record was created ) and update it.

Any advice would be appreciated, but I'd really like to know how Discovery matched a CI like LapTop1 to a record in the CMDB.

[Mark Stanger · Accepted solution]

This article on Discovery Identifiers should answer your question.

Discovery Identifiers - ServiceNow Wiki

[HugoFirst]

Mark,

Thank you for the quick reply and valuable pointer.   It looks like the CI identifier is the key.

In looking at my instance, the CI identifier of interest appears to match on serial number and class name.

For other people reading this, here's a link to the pertinent section:

Discovery Identifiers - ServiceNow Wiki - 9 Base Identifiers

[Akshay62]

After Discovery classifies a CI, Discovery identifier determines if the device already exists in the CMDB.Discovery knows this by information through the data collected by each probe which is send to different machines for collecting information.