I am trying to graph sflow data in Elastic Search but I can’t get it to work as I would like it to. The challenge that I am facing is that the data is counters and continuously increasing. This does not make for a very useful graph.
Is there any way to calculate the delta? Or do I need to do that via Elastic Search?
The data (output_octets) is in bytes. To get the throughput I needed to first multiply by 8 to get bits. Then divide by 1024*1024 to get Mbit. Lastly, divide by the interval.
Then I get a value that is close to what I expected. Not sure if it’s correct though. Does this look right to you guys?
Turns out there was an inbuilt functionality to add the interval for the derivative. My unit is sampling every 10 seconds. Adding 10s in the Unit field gave me something close to what I expected. However, it is still around 10x too high.
My syslog-ng sends every 10m a message log to graylog with its stats, i then do some processing in graylog to create the fields d_graylog_processed, d_graylog_dropped, etc…
for example d_graylog_processed containers the number of messages that were processed by syslog-ng regarding the graylog destination on the last 10m.
I was able to make it work with sum and derivative.