Spectrum unable to read Transparent Bridge Table

Products

• CA Spectrum

Issue/Introduction

When trying to view the 'Transparent Bridge Table' view for Cisco Catalyst switches Spectrum seems to be unable to read the transparent bridge table correctly.

   - In the Transparent Bridge Table > Forwarding Table sub-view nothing is shown.
   - After clicking the Per VLAN button to select the VLAN to show the table for, the only VLAN that even shows in the list is "default(0)" and none
        of the actual VLANs on the device appear in the list.

 

 

Cause

The devices were not allowing access when contexts were passed in SNMPv3 polling.

Environment

Release : 10.x

Component : Spectrum Core / SpectroSERVER

Resolution

Devices will instance the transparent bridge (1.3.6.1.2.1.17) tables to present views for the individual vlans
  configured on the device.

SNMPv2

When polling via SNMPv2 these instances are accessed by appending @<VLANID> to  the community string in the request

SNMPv3

When polling via SNMPv3, the instanced data is accessed by providing a 'context' string along with the request. The context name is
   in the form of vlan-<VLAN ID>

 

In the case of SNMPv3, it is not enough to configure an SNMPv3 user but access needs to be granted to requests using the context ids.

 

FIX: update the SNMPv3 configuration granting access to the v3 contexts

ex. 

snmp-server group v3group v3 auth context vlan- match prefix

Note: Older versions of IOS may not support the match prefix and may require to add each vlan separately

 

After configuring the devices to allow access to the vlan contexts the 'Transparent Bridge Table' view completely populated and
  presented all vlans in the 'perVlan' dialog