Plotting inbound and outbound traffic to a specific network with Cacti or Mrtg

[firmanperdi]

Hi Guys,

First of all, pardon me if i post on a wrong sub forum.

So, I have a question about the methods to plot inbound & outbound traffic to a specific network, as you can see the topology below :

We have a Cisco 7609 as the Router Edge and 2 Uplinks to different ISPs. As by now I'm wondering is there any methods to mark inbound traffic from both ISP A and ISP B for a specific network ?

For example : Is it possible to plot traffic that only going to network 202.138.1.0/24 from the Interface to ISP A with cacti or MRTG ?

If it possible, what method to use ? 
Is it something to do with DSCP ? As far as I know that DSCP does marks the packets. But then, what to combine with this DSCP, so in the end I can generate OIDs to Plot ?

I'm sorry for my english, I hope you guys understand what I'm trying to ask here.

Cheers !!

[Seb Rupik · Accepted solution]

Hi there,

This a perfect example of a problem best solved with a netflow collector. I've been using an opensource tool called nfsen and would recommend that.

http://nfsen.sourceforge.net/

You would need to configure a collector on each router-ISP interface. These would export to different ports on the collector giving two different concurrent flow sources.

On nfsen as well as displaying an aggregate of all flows from a collector, you can also configure 'profiles' which display a live graph on a filtered subset (in your case 'net 202.138.1.0/24') of the flow data and allow you to run further queries on.

cheers,

Seb.

[firmanperdi]

Hi Seb,

Thanks for your reply, I'm currently doing some search about NFsen and seems like it is not too hard to configure. So, I'll give it a try. 

I hope this works.

Thank you !