Minor Description
Dear Observium,
We have some Cisco Nexus 5548UP switches running NX-OS version 7.0(1)N1(1) & 7.3(6)N1(1) - there are FEX'es uplinked to the parent Nexus switches.
We are using Observium Professional Edition version 22.6.12145 (rolling)
The issue for us is that when we have the 'vlans' discovery module running and the MIBs CISCO-VTP-MIB and Q-BRIDGE-MIB are enabled, to build the 'VLANs' tab/list in Observium under the device we see a CPU spike, from around 20% avg. up to 50% avg. when discovery is running and the discovery often takes a very long time running over 4400 secs and times out.
If I disable the CISCO-VTP-MIB and 'vlans' discovery module so that we don't do VLAN discovery when running discovery then everything if fine but then we are of course missing newly created VLANs are added to the VLANs tab in Observium.
When looking deeper into the process CPU usage on the Nexus switches I can see that it is the 'vlan-mgr' and 'snmpd' process the uses all the extra CPU which what was pointed me towards this being an issue while discovering VLANs.
I'm not saying that this could not be an Cisco Nexus issue but I think it is strange that we see this issue both on 7.x and 7.3.x NX-OS versions.
I'm not sure if it is the way that the VLAN discovery is done in that every port needs to be traversed for every VLAN or vice versa and the because we both have a lot of VLANs and ports this is an issue.
I have attached output from one of the devices: "./discovery.php -d -m vlans -h dc4-1-a6-nx01.netic.dk" when the 'vlans' discovery module is enabled & CISCO-VTP-MIB is disabled and we don't see the issue, but then of don't get our VLANs tab updated and then again when the 'vlans' discovery module is enabled and CISCO-VTP-MIB is also enabled.
(i breaked the discovery after running for over 10 minutes and still not finished)
It seems that CISCO-VTP-MIB is needed for correct VLAN discovery and update of the VLAN tab/list in Observium.
Regards, Jacob Hassing