[c-nsp] 6500 Netflow

[Gert Doering]

Hi,

On Thu, Apr 17, 2008 at 09:43:22AM -0700, Ian Cox wrote:
> Prior to 12.2(33)SXH netflow on the 6500 was enabled on a global 
> basis. Which is different to all the router platforms where it is 
> enabled on a per interface basis. In 12.2(33)SXH for the 6500 and 
> 12.2(33)SRA for the 7600 NDE was finally changed to be enabled on a 
> per interface basis like other cisco platforms.

This is good news.

I've heard different rumors on the actual implementation, though.  So maybe
you can clarify?

One rumor was that SXH and SR* still have *all* flows in the netflow TCAM,
and only filter on output, in the RP CPU.  Which would mean that this feature
reduces the amount of data exported to the collectors, and the amount of
processing needed there to filter wanted/unwanted interfaces (which is good),
but that it would not reduce netflow TCAM contention, and possibly even
increase RP CPU load.

The second rumor is that SRC is actually filtering already upon *collection*,
so that the TCAM usage and RP CPU load would dramatically go down if you
only have netflow collection enabled on a few interfaces.


Soooo... any truth in this?

gert
-- 
USENET is *not* the non-clickable part of WWW!
                                                           //www.muc.de/~gert/
Gert Doering - Munich, Germany                             gert at greenie.muc.de
fax: +49-89-35655025                        gert at net.informatik.tu-muenchen.de
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 304 bytes
Desc: not available
Url : https://puck.nether.net/pipermail/cisco-nsp/attachments/20080417/1b4d4d8e/attachment.bin