Re: about output ifIndex: 0

Date view Thread view Subject view Author view

Subject: Re: about output ifIndex: 0
From: Dave Plonka (plonka@doit.wisc.edu)
Date: Mon Dec 17 2001 - 15:53:02 CST

On Thu, Oct 18, 2001 at 01:18:58PM -0400, Qingbo Jin wrote:
> Hi :

Sorry for the delay...

>     I have a question about NetFlow, what 's the meaning of 
> output ifIndex: 0  inside a flow?? Does that mean it is a useless flow and
> the router will not deliver it?

See how that's answered in this FAQ:

   http://www.caida.org/tools/measurement/cflowd/newfaq.xml

> why flowscan skip this?

For unicast traffic, I think it means that it wasn't forwarded.  This
is evidenced by the fact that that is how Ciscos seem to report things
that were ACL-blocked or routed to Null0.

If it was multicast - then we don't know how the router handled the
traffic, since the NetFlow data format doesn't report the set of egress
interfaces for multicast flows.  We just know that that traffic arrived
at the exporter.

Dave

-- 
plonka@doit.wisc.edu  http://net.doit.wisc.edu/~plonka  ARS:N9HZF  Madison, WI

--
Help        mailto:majordomo@net.doit.wisc.edu and say "help" in message body
Unsubscribe mailto:majordomo@net.doit.wisc.edu and say
"unsubscribe flowscan" in message body
Archive     http://net.doit.wisc.edu/~plonka/list/flowscan/archive/

Date view Thread view Subject view Author view

This archive was generated by hypermail 2b25 : Mon Dec 17 2001 - 15:59:44 CST