VLAN info via SNMP missing?

[Patagoche]

I've been using LibreNMS monitoring software for almost 2 years now. It's a really GREAT monitoring platform and they also have a very helpful community.
I noticed that netonix switches did not show a VLAN tab with info about VLAN names, tags and inter and interfaces on LibreNMS but other vendors do, so I addressed this issue to some of the devs there.
I would like to know if you provide VLAN info via SNMP, and if you do, which MIBs do you support for this? AFAIK they are already using the mib you provide in this forum -I don't know if they are using an older version-.
Any info you need I would be glad to help out.

[Eric Stern]

We support Q-BRIDGE-MIB for VLAN information.

Here is a dump from one of my switches with a single VLAN.

464: dot1qVlanStaticName.1 Management
465: dot1qVlanStaticEgressPorts.1 fffffffffffffffc0000
466: dot1qVlanForbiddenEgressPorts.1
467: dot1qVlanStaticUntaggedPorts.1 fffffffffffffffc0000
468: dot1qVlanStaticRowStatus.1 active(1)

[Patagoche]

I'm getting back to you... Today I made a few tests and got this results:

Code: Select all

$ snmpget -v2c -c<mycommunity> <myhostname> -m Q-BRIDGE-MIB -M /opt/librenms/mibs dot1qVlanVersionNumber.0
$ Q-BRIDGE-MIB::dot1qVlanVersionNumber.0 = No Such Object available on this agent at this OID

So I'm guessing you are not fully supporting Q-BRIDGE-MIB then, or could there be any other reason it doesn't return anything there?

[Eric Stern]

Two reasons. The number at the end should be the VLAN ID, there is no VLAN with ID 0.
Also we do not support dot1qVlanVersionNumber. Doing an SNMP walk will return everything and you can see what is available.

[Patagoche]

Here is my conversation with the LibreNMS team:

[14:38]<Andreser> I asked them about Q-BRIDGE-MIB::dot1qVlanVersionNumber.0 = No Such Object available on this agent at this OID
[14:39] <Andreser> they responded: The number at the end should be the VLAN ID, there is no VLAN with ID 0. Also we do not support dot1qVlanVersionNumber. Doing an SNMP walk will return everything and you can see what is available.
[15:00] <@laf> Andreser: they are ignoring the standard then. Version isn't a per vlan thing it's what version the device is configured with so walking shouldn't make a difference. In fact that's not even a table so unless they just chuck a random id on the end then it's just plain wrong.
[15:06] <@murrant> Andreser, yeah, they have not followed the standard: dot1qVlanCurrentTable is not populated...
[15:07] <@murrant> A table containing current configuration information for each VLAN currently configured into the device by (local or network) management, or dynamically created as a result of GVRP requests received.
[15:13] <Andreser> Ok, thank you for the info. I'll ping them about this and get back to you. To be clear about this, if they upgrade their firmware to correct this, on the next discovery the vlan tab should be automatically populated in librenms?
[15:14] <@laf> Andreser: Yes, we check the version first and then continue on. Using the standard Q-BRIDGE-MIB info we then populate vlans

Could you please check this out and get back to me?
Additional info & Support with libreNMS team @ http://webchat.freenode.net/?channels=##librenms
Thank you!!

[tonym]

FYI, here is what happens in LibreNMS to pull in info from Q-BRIDGE-MIB:

1. Check dot1qVlanVersionNumber.0 to see if Q-BRIDGE-MIB is supported (should be 1 or 2)
2. Walk the VLAN names from dot1qVlanStaticName (vlan indexes there need to match those in other spots of the MIB, usually they are the vlan id for stability if vlans get added/removed)
3. we walk dot1qVlanCurrentEgressPorts and dot1qVlanCurrentUntaggedPorts Which must contain all currently provisioned ports. Example output with two vlans:

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dot1qVlanCurrentEgressPorts.0.1 = "FE FF FF 00 00 00 00 00 00 00 00 00 "
dot1qVlanCurrentEgressPorts.0.1351 = "11 00 00 00 00 00 00 00 00 00 00 00 "
dot1qVlanCurrentUntaggedPorts.0.1 = "FE FF FF 00 00 00 00 00 00 00 00 00 "
dot1qVlanCurrentUntaggedPorts.0.1351 = "00 00 00 00 00 00 00 00 00 00 00 00 "


Thats it really. You should probably fully follow the standard to make sure other NMS support things properly. Here is the RFC: https://tools.ietf.org/html/rfc4363

I can test things out if you reach out :)

[Eric Stern]

I'll try to address this in the near future.

[Patagoche]

Thanks Eric, keep us posted please. I can also "besta test" your update with librenms when it's available, glad to help.

[Patagoche]

I just realized there is an update to your firmware v1.4.8rc5 Released 5/26/2017 which states: - Improved Q-BRIDGE-MIB support - RC5.
Is this about VLAN reporting?
FYI I just tested with my NMS and it's still not reporting any info about VLANs.
Greetings.

[Eric Stern]

I updated Q-BRIDGE-MIB support in RC5 according to this post: viewtopic.php?f=6&t=2762&p=19349&hilit=bridge+mib#p19125

If it still doesn't work someone will have to do some testing to figure out why librenms still doesn't like it and I'll update it accordingly.