When there is virtual interface involved in Network Router/Switch Pattern discovery, e.g. Port-Channel2, GigabitEthernet0/0.3,  the Shared Library 'SNMP - Switching' does not filter out records with null value for interface_number (ifindex) on affected instance versions. This would cause identification payload processing error on dscy_switchport table because the OOTB identification rules on dscy_switchport table requires interface_number value.


The typical symptom is observing the following payload processing error in Pattern logs:

Insertion failed with error,In payload missing minimum set of input values for criterion (matching) attributes from identify rule for table [dscy_switchport]........


If we create a step to filter NULL value interface_number rows, the Pattern can insert dscy_switchport records correctly.


The PRB1286427 has been fixed in Kingston Patch 8 and London.




Steps to Reproduce

Run Network Router/Switch Pattern discovery on network devices which have virtual interfaces.

Observe the payload identification error in the Pattern log.


Add one pattern step in "SNMP - Switching" library, see attached screenshot:



step {
name = "Filter empty interface_number from dscy_switchport"
comment = "Filter empty interface_number from dscy_switchport"
filter {
src_table_name = "dscy_switchport"
target_table_name = "dscy_switchport"
condition = is_not_empty {get_attr {"dscy_switchport[].interface_number"}}



Related Problem: PRB1286427

Seen In

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Intended Fix Version


Fixed In

Kingston Patch 8

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Article Information

Last Updated:2018-12-06 12:04:25