How can we prevent Duplicate CI for Name+Serial Number IRE combination

[Suvetha S]

Hi All,

We have changed the OOB IRE rule for Server table to look for Name + Serial Number combination. So if a server comes in with a matching Serial Number and Name IRE will update the existing records. In certain cases, Discovery couldn't fetch the serial number from the target servers and IRE is creating a duplicate CI. One CI - Name & Empty Serial Number, second CI- Same name with Serial number value. Initially we thought of entering serial number values for cmdb_serial_number manually to avoid the issue, but it didn't work as expected. Whenever Discovery is bringing empty serial number its creating a duplicate in the system. Any suggestions will be helpful. 

[newhand]

@Suvetha S

Maybe it's a bug about Discovery. 

What about collecting all the logs and raise an HI CASE..

And what I can suggest is to create a trigger (before insert) and check if the CI has both a name and a Serial Number. If the Serial Number is missing, reject the insert action and store the CI information in a custom table or raise an email to notify the team.

[Suvetha S]

Hi @newhand Thanks for your response, How can we create a trigger? I do not have any idea about it

[newhand]

@Suvetha S 
To create a business rule , you can refer this link。
https://docs.servicenow.com/bundle/sandiego-api-reference/page/script/business-rules/concept/c_Busin... 

Basically,

1. Define a trigger.

2. Specify some conditions.

3. Write your logic script.
    And here, you can use the code below to reject the insert.

current.setAbortAction(true);

[Amit Gujarathi]

HI @Suvetha S ,
I trust you are doing great.
To address the issue of duplicate Configuration Items (CIs) being created in ServiceNow due to missing serial numbers, the suggestion to create a business rule (before insert trigger) is a practical approach. This business rule can check whether both the name and serial number are present for a CI. If the serial number is missing, the rule can either reject the insertion of the CI or take alternative actions like logging the information or sending a notification.

if (!current.serial_number) {
    current.setAbortAction(true);
    // Optionally, add code here to log the information or send notifications
}