Network Management
SNMPv2 Authentication Failure Due To VLAN Context Polling
This article is created to explain why SNMPv2 authentication failure occurs when a VLAN context polling occurs.
First published date
8/5/2022 3:26 AM
Last published date
8/5/2022 3:26 AM
Overview
A target device sends an SNMPv2 authentication failure trap showing its community string appended with a VLAN ID(communitystring@VLANID).
This happens when VLAN context polling is happening on the target node.
For SolarWinds to access the BRIDGE-MIB to fetch the VLAN data, the VLAN ID needs to be appended on the community string as there is no possible way to get all VLAN details without using the VLAN context polling as this is by design on the target devices itself that utilized the BRIDGE-MIB
This happens when VLAN context polling is happening on the target node.
For SolarWinds to access the BRIDGE-MIB to fetch the VLAN data, the VLAN ID needs to be appended on the community string as there is no possible way to get all VLAN details without using the VLAN context polling as this is by design on the target devices itself that utilized the BRIDGE-MIB
Product section
User Device Tracker
Cause
The cause of the SNMPv2 authentication failure is the VLAN context polling.
Resolution
Workarounds
1. Disable the L2 and L3 polling for UDT and NPM.
*Disabling L2 and L3 polling on NPM means you will not be able to fetch topology data that can be used in creating Orion maps
*Disabling L2 and L3 polling on UDT means you are disabling the main functionality of the UDT, which is to poll the port status and its corresponding details.
2. Disable SNMPv2 authentication traps on the target device.
3. Use SNMPv3 as described in the below KB article.
SNMPv3 BRIDGE-MIB commands need to be added to Cisco devices
Other reference KB articles.
SNMP discovery with @ postfix after community string in Orion Platform
1. Disable the L2 and L3 polling for UDT and NPM.
*Disabling L2 and L3 polling on NPM means you will not be able to fetch topology data that can be used in creating Orion maps
*Disabling L2 and L3 polling on UDT means you are disabling the main functionality of the UDT, which is to poll the port status and its corresponding details.
2. Disable SNMPv2 authentication traps on the target device.
3. Use SNMPv3 as described in the below KB article.
SNMPv3 BRIDGE-MIB commands need to be added to Cisco devices
Other reference KB articles.
SNMP discovery with @ postfix after community string in Orion Platform