Re: [Netdisco] What LLDP OIDs are required for topology?

[Ingen S. J. v. (ICTS) <j.v...@ut...>]

Hi Chuck,

On Thu, 2011-05-05 at 14:55 -0400, Chuck Brown wrote:
> Our implementation of Netdisco has a long list of "Devices Orphaned by
>  missing topology info" (report under the Devices page).
> 
> Would these devices be orphaned because of missing information in the
>  LLDP OIDs?  If so, are there specific OIDs that must be populated? 
>  Or, could there be other reasons these devices are orphaned?

A device will also be orphaned if it is seen by a neighbor, but doesn't
see neighbors itself. This might happen if the device sends and receives
LLDP but the neighbor is configured not to send LLDP packets out.
Another cause may be that the device supports LLDP but doesn't implement
the MIB.

Oh, I guess this can also happen if one of the devices doesn't send its
management IP in the LLDP packets, but only transmits a MAC address.
Netdisco doesn't handle the latter correctly.

> I'd like to work with the device vendors to implement any changes
>  necessary to un-orphan these devices.

Perhaps it would be good to start with a discover for two neighboring
devices with debugging on; that might give some hints where to start
looking.


fwiw: I have a lot of "orphans" in my topology for various reasons. Two
examples:

- all Cisco fat APs connected to HP switches are orphaned (the APs don't
support LLDP, the HPs don't send CDP but do process received packets).
Afaik, Cisco doesn't have plans to implement LLDP on fat accesspoints.

- our Cisco Cat6k boxes are orphaned; they support LLDP but still
haven't implemented the MIB. I still hope they will implement the MIB
some day...


Regards,

Jeroen van Ingen
ICT Service Centre
University of Twente, P.O.Box 217, 7500 AE Enschede, The Netherlands