I would love to see a Mac Address forwarding table grab in observium for L2 devices. Maybe it's already there, but I couldn't find it.
In NetDisco, this feature is implemented using the 'macsuck' tool. *http://www.netdisco.org/readme.html#glossary*
I've implemented it before in sloppy perl using the Bridge mib. * http://www.cisco.com/en/US/tech/tk648/tk362/technologies_tech_note09186a0080... *
The gist for collection is: - determine the list of active vlans - for each vlan get a list of mac addresses per 'bridge port' - lookup a translation of bridgeport to ifindex
If you correlate this data with a global ARP table and DNS, you get a killer feature.
"Lookup the switch port where a given host was last seen. (and hopefully where it still is)"
Because this can be a pretty dynamic dataset, you'll also probably want to maintain the list by putting a last seen datestamp and rolling out old entries.
I think I've found a few hints at some development interest in the past about this sort of feature.
Has it gotten any traction?
Cheers,
Joel