[f-nsp] per vlan/ve mrtg-graphs / snmp-counters on the Netiron MLX

[Richard A Steenbergen]

On Sun, Jan 20, 2008 at 09:59:08PM +0100, Gunther Stammwitz wrote:
> Hello colleagues,
> 
> 
> I'm trying to graph vlans or virtual interfaces (VEs) using mrtg on th 
> Netiron MLX but am not succesful.
> 
> Mrtg is detecting the virtual interfaces but the speed is missing. After 
> fixing this mrtg is working fine but the counters are staying at zero.
> 
> Any idea how to get this working?

It doesn't. This is probably the single most requested feature from 
Foundry users I speak to, but the offical party line is that they have no 
plans to implement it since "you can just get this data from sFlow" 
(sampled of course). There is a layer 2 vlan counter on newer platforms 
(like MLX/XMR), but it doesn't distinguish inbound/outbound, so it doesn't 
help for most applications.

I have some fairly old and dirty code floating around (as an extension to 
the sflowd example implementation for my libsflow project) which 
replicates subinterface counters out of sflow data, if anyone wants to 
play with it. Note that it ONLY replicates subinterfaces (i.e. if you have 
port GigabitEthernet1/1 and GigabitEthernet1/2 both with vlan 123, it only 
generates data for GigabitEthernet1/1.123 and GigabitEthernet1/2.123 
counters, but not as a Ve123 counter).

To download:

Get libsflow from http://sourceforge.net/projects/libsflow/
And dev ver of sflowd from http://www.e-gerbil.net/ras/sflowd-0.95.tar.gz

I don't know why I'm bothering to mention this here, it's far from the 
most user friendly piece of code out there (its intended as a reference 
example for using libsflow, not as an end-user application :P), but there 
it is. Its also complicated by Foundry's irrational ifIndex grouping 
inconsistancies between platforms and versions. I suppose if there is some 
interest I could whip up a simple SNMP agent interface to the sFlow data 
(to be a little more generic, this code is currently designed for directly 
outputting to rrdtool, which clearly doesn't work for everyone :P).

Any interest?

-- 
Richard A Steenbergen <ras at e-gerbil.net>       http://www.e-gerbil.net/ras
GPG Key ID: 0xF8B12CBC (7535 7F59 8204 ED1F CC1C 53AF 4C41 5ECA F8B1 2CBC)