FastNetMon Advanced Mikrotik configuration

As first step, please install at least RouterOS 6.38 because it has very urgent fix for Netflow implementation on Mikrotik:

*) traffic-flow - fixed flow sequence counter and length;

We suggest using ssh for configuration process but you also could use WinBox or Webfig for this task (select “IP”, “Traffic flow” on left menu).

As first step, please open Netflow configuration:

/ip traffic-flow

And enable Netflow for all ports with affordable timeouts:

set enabled=yes
set interfaces=all
set cache-entries=128k
set active-flow-timeout=00:01:00
set inactive-flow-timeout=00:01:00

128k value works for almost all carried-grade devices. But if it does not work for you, try 64k, 32k, 16k.

Change to Netflow target configuration:

/ip traffic-flow target

And specify FastNetMon here (replace by FastNetMon’s address):

add dst-address= port=2055 version=9 v9-template-refresh=30 v9-template-timeout=30

And from FastNetMon Advanced side you need to change:

sudo fcli set main average_calculation_time 60
sudo fcli set main average_calculation_time_for_subnets 60
sudo fcli commit

Also, in v6.44 testing release Mikrotik added option to set lower than 60 seconds timeout and you can try 30 seconds for active and inactive timeouts for testing.