Showing posts with label Cisco MARS Sflow. Show all posts
Showing posts with label Cisco MARS Sflow. Show all posts

Thursday, March 29, 2007

Netflow from a HP Switch?

I was at a MARS meeting with a potential customer the other day, and it was one of those meetings where all is going great, the customer loves the idea of what MARS can do, and then we get onto what devices the customer has in their network.

Ok, HP Switches across the board, some 3rd party firewall in a DC that they are not allowed to touch, no IDS/IPS in place or any plans/skills for etc.. if you`ve been there you will know!

Coming home from the meeting got me thinking.

I know most high end HP switches can export Sflow, as opposed to Netflow that is supported by MARS.

Now what if there was a tool that could convert Sflow to Netflow?, at least we would be able to get some useful info into MARS, for anomaly detection at least.

Remember, MARS does not store netflow by default, only the records that are part of an incident. But you do get the option to store Netflow, though this is not recommended! (This has the potential of slowing the system by drastically increasing the events per second that it must process.)



Now i have not tried the following, or do i recommend it (i dont even have a Sflow supported HP Switch), nor do know if it would be supported by MARS, but here is the theory!
There is a tool called the Sflow Toolkit, by a company called InMon

This runs on Linux, Solaris or Windows, and will take Sflows and convert them to Netflow, to forward onto a Netflow collector such as MARS.

The following example shows sflowtool converting sFlow packets into NetFlow and sending the NetFlow packets to a NetFlow collector specified by a host and port.


sflowtool -c netflow.inmon.com -d 9991 > /dev/null

If anyone has ever tried this, let me know.