My goal is monitoring the cumulative bandwidth used on my network and track the total usage in GB/TB per month from each network port, e. g. .
I’m tying with Grafana / InfluxDB / Cacti + Plugin  and or Collectd.
From both cacti and collectd, I can’t generate the expected value. I have tried the queries with:
But every query show different value from the Cacti Total In/Out graphs
Any help would be greatly appreciated