I was trying to implement an internet traffic monitoring via Telegraf.
I used input plugin [[inputs.snmp]]. Since monitored device reports just snmp1, I have to set
version = 1. This brings the limitation of use just 32-bit Octets counters (e.g. IF-MIB::ifInOctets.2 = Counter32)
Since these counters ‘flip-over’ to zero once the data type size limit is reached (maximum value for a 32 bit unsigned integer is 4,294,967,295), further use, monitoring and analysis of these data is very limited.
Subsequent data points with a negative difference of counters’ values (in the time when 32-bit limit of the counter is reached) make whole metric inapplicable.
It forced me to write down a separate script which gathers non-negative difference between octet counters and writes it into InfluxDb.
It would be nice to have such functionality implemented into Telegraf snmp input plugin.