On Mon, 28 Jan 2019 17:47:54 +0100 Vinsonnaud Ludovic <ludovic.vinsonnaud@institutoptique.fr> wrote:

It seems it doesn't like the PoE on my Dell N2048P because of a NULL value in
"classification" column.
Do you have an idea ?

I have no experience with the POWER-ETHERNET-MIB itself, as I was not
directly involved in the development of the PoE support (and
interestingly enough, the dev who did signed off this list right after
you posted your question :-D ).

However, the information comes from the `pethPsePortTable`, and the
classification value comes explicitly from the
`pethPsePortPowerClassifications` column.

NAV's model does not allow the classification field to be empty, so it
would be interesting to see what your Dell switch reports in this
column. Are you able to pull the full contents of
POWER-ETHERNET-MIB::pethPsePortTable using NET-SNMP command line tools?

If there is a port with no value in this column, is the port powered at
the moment? The MIB mentions that the classification value is only valid
as long as there is a powered device connected to the port - so NAV's
model requirement to have a value in this might not be valid.