Unable to modeling an SNMPv3 device in Spectrum after it was modeled before, and destroyed

Products

• CA Spectrum
• DX NetOps

Issue/Introduction

After successfully modeling an SNMPv3 device in Spectrum , it was needed to destroy it.
When trying to modeling it again, the next error message is received

SPC-OCC-10447: Error discovering the device at xxx.xxx.xxx.xxx Device is responding to ICMP but not to SNMP.

Strangely a sapwalk executed from the spectroSERVER ends successfully.

Environment

Release : 10.4

Component : Spectrum Alarm & Event Management

Cause

A network Capture show the device return 1.3.6.1.6.3.15.1.1.4 (usmStatsUnknownEngineIDs: "The total number of packets received by the SNMP engine which were dropped because they referenced an snmpEngineID that was not known to the SNMP engine.")

Resolution

As per the network capture, this seems to be caused by SNMPv3 Engine's ID

A first option would be to follow the steps described on next technical document to clear the SNMPv3 cache in Spectrum

https://ca-broadcom.wolkenservicedesk.com/external/article?articleId=139839

If that does not work, another option is:

1. manually create a GnSNMPDev model using new model by type and give the IP of the device you are trying to model

2. once it is created, manually change the community string to be the correct v3 string (#v3/P:MD5^<authpassword>:DES^<privacypassword>/<userid>).

3. Then right click, and select – Reconfiguration – Reset SNMPv3 Credentials.

If the above steps still doesn't work, you may try destroying the GnSNMPDev model created (destroying the model is supposed to remove the entry from the cache) and try modeling it by ip.