Netflow usage wrong?

RouterOS General
1

Hi all

I have had netflow running on my router for quite a while and only recently decided to compare data usage to what my radius server reports.
The usage data did not match up at all. It was not even close…

So I had the traffic flow settings on default until 4 days ago, but then I read in some Cisco article that they recommend setting the active flow timeout to 1 minute and I also decided to increase the cache entries value.
Now I look at the last couple of days and the usage records between what radius says and netflow are still out with hundreds of megabytes.

I don’t know if I’m doing something wrong, but everywhere I hear, people say netflow data is quite accurate.
My set up at the moment is:

[admin@MikroTik] /ip traffic-flow> print
                enabled: yes
             interfaces: ether2-master-local,vlan109
          cache-entries: 128k
    active-flow-timeout: 1m
  inactive-flow-timeout: 15s

[admin@MikroTik] /ip traffic-flow> target print
Flags: X - disabled 
 #   ADDRESS               VERSION
 0   10.0.15.230:9996      5

I use ManageEngine Netflow Analyzer as my collector. My RouterOS is version 5.8

Any suggestions or ideas as to what I can do?

2

check ROS v5.13 - NetFlow is rewritten a bit here

also, check, what kind of traffic you’re measuring in both cases