Hi all.

I just have a question regarding netflow. We recently setup a nfsen, and wanted to try to gather more information about our traffic regarding where it went and how it gets there. But one of the important things is AS-numbers, and according to the wiki (https://wiki.mikrotik.com/wiki/Manual:IP/Traffic_Flow) RouterOS currently doesnt include BGP-AS numbers.

Will MikroTik add it to RouterOS in v6 or is this something we will have to wait until we get the unicorn?
Also, how have you, the other peeps on this forum, handled this part of the netflow data, even without AS-numbers? Do you have some other way to get this information or you use some other technique?

Best Regards, Joar

It's been requested for years and never made it in, not really sure what the technical hurdle to this is apart from perhaps too many expensive route table lookups to get that information (RIB vs FIB), think about how long it takes to search the route table sometimes compared to other routing OS's.

One way to do it - a shitty workaround - is run BGP software on your monitoring server, import the routes and do lookups locally for AS information based on dst/src IP. You'd do this on the reporting side so the flows remain as they are and just as your reporting you pull AS information (or a script to run through saved flows from last ~x minutes to modify the flow with the AS details)

I'm sure there are other work-arounds as well, but having it in the flow directly would be awesome.