Min/Max Transmit bps

robdawley

Hi All,

Can anyone please advise how these metrics for an interface are calculated and stored by Solarwinds NPM.  It looks like the values could be extremely useful for us for historic analysis where we need to track back to 2am in the morning and see if an interface was maxing out, but I was curious how this data is derived.  If Solarwinds only polls the interface every 2 minutes is the interface aware enough to give Solarwinds the max from the last 2 minutes or does the min / max counter get set and updated by a defined confguration on the switch.

I took a look through the documenation but this didn't seem clear - I hope this question makes sense.

Regards,

Rob.

mesverrum

in SNMP bits per sec is an incrementing counter that gets polled every x minutes, and the difference between the last poll and the current is divided by the interval.  So it is always an average across a period of time and short bursts don't show up.  That's common to all SNMP based polling tools.  You would also measure bps along with the incrementing counters for things like packets dropped, errors, and buffer queues to have a sense of what happens in the gap periods, and you can also configure some devices to generate trap type messages if there are periods where the interface utilization exceeds a certain threshold.  Polled data always requires a bit of calculating and inference but it is accurate enough for day to day work.