CI Name getting overridden during Discovery (SNMP Classify) – unable to retain DNS-based name

DeebikaS1775775
Kilo Explorer

Hi Team,
I am facing an issue with ServiceNow Discovery (SNMP Classify) for network printer devices.
Scenario:

Device is discovered via SNMP
Class is correctly identified as Printer
DNS name is coming correctly:
AMI-PLA-CP01.teachersfcu.org


However, CI Name is getting set as:
datacard printer

 

Expected behavior:

CI Name should be derived from DNS / hostname:
AMI-PLA-CP01

 


What I checked:

Identification Rules → Working fine (falls back to name)
Reconciliation Rules → No overriding issue

 

From the discovery logs, identification is skipping multiple identifier entries and only matching based on name:

Rule 1: sys_object_source → Skipped Identifier Entry
Rule 2: product_instance_id → Skipped Identifier Entry
Rule 3: serial_number → Skipped Identifier Entry
Rule 4: serial_number → Skipped Identifier Entry
Rule 5: name → Match

Final outcome:
Exploring CI: datacard printer

 

 

This indicates that:

  • No strong identifiers (serial number, product_instance_id, etc.) are available
  • Identification falls back to name-based matching
  • The name being used is already "datacard printer", which comes from SNMP classification. How to fix this ?
4 REPLIES 4

pr8172510
Tera Guru

Hi @DeebikaS1775775,

 when Discovery cannot obtain stronger identifiers such as serial number, product_instance_id, or sys_object_source.

In your logs, IRE is falling back to the Name identifier, and the value being passed to IRE is already "datacard printer" rather than the DNS hostname.

check

• SNMP Classification results
• Values returned by sysName and printer-specific MIB attributes
• Printer Discovery Pattern output
• Discovery logs to identify which attribute is populating the CI Name field



SNMP Discovery

Name populated as "datacard printer"

IRE falls back to Name identifier

CI matched/created as "datacard printer"


Since DNS is being collected correctly, review the SNMP Classification and Printer Discovery Pattern to determine why the Name attribute is being populated from the printer description instead of the hostname.


This is typically a Discovery data population issue rather than an Identification or Reconciliation Rule issue.

Based on the guidance received, I did further validation using Discovery logs and ECC payload for an SNMP‑based printer.


ECC Queue Analysis
SNMP - Classify Output:

dns_name = AMI-PLA-CP01.teachersfcu.org 
initial name derived = ami-pla-cp01 

SNMP - Printing Output:

dns_name remains correct 
However, CI name is eventually overwritten to:

datacard printer 

 

 

Could you please confirm:

Which part of Discovery logic is responsible for overwriting the name field after SNMP Classify?
Is the name being set from:

sysDescr / hrDeviceDescr
or Printer MIB attributes via PrintingHandler?


What is the recommended approach to ensure CI name is derived from:
DNS / sysName instead of printer description

 

 


Expected Behavior
CI Name → AMI-PLA-CP01 


Current Behavior
CI Name → datacard printer 

Hi @DeebikaS1775775,

Based on your ECC analysis, the DNS name is being collected correctly during SNMP Classify (ami-pla-cp01), so the overwrite is occurring later in the SNMP - Printing phase.

IRE is not changing the value. It is using the value already populated by Discovery.


To identify the source of the overwrite

  1. Open Discovery Patterns and review the SNMP - Printing pattern.

  2. Check the Pattern Debug output to see which attribute is mapped to the CI name field.

  3. Review values returned from:

    • sysName

    • sysDescr

    • hrDeviceDescr

    • Printer MIB OIDs

  4. Compare those values with the final CI name (datacard printer).

 


If the pattern is mapping a printer description field to name, the recommended approach is to update the pattern logic so that DNS/sysName is used for the CI Name instead.

This is a Discovery pattern mapping issue 

Yes, based on further validation, it appears that there is no SNMP Printer pattern available in this instance.
From Discovery logs:

SNMP Classify is correctly setting the hostname (AMI-PLA-CP01)
Identification is working as expected
However, during SNMP - Printing stage, the CI name is overwritten to “datacard printer”

So the issue is not related to pattern mapping. It seems that printer discovery is handled through SNMP probes/handler (SNMP - Printing) rather than pattern-based logic in this instance.
Can you confirm the recommended approach to control CI name in this handler-based discovery scenario?