[c-nsp] NetFlow for billing on 6500/SUP720-3B

[TCIS List Acct]

Hi all,

A bit of background...

We are preparing to deploy our first pair of 6509s with a SUP720-3B supervisors 
and WS-X6548-GE-TX line cards (we may also have a few WS-X6748-GE-TX cards as 
well).  These will be used for core/customer distribution primarily, with a pair 
of Juniper M7i routers at the edge.  These switches are used in a Data Center / 
Co-lo type environment and are replacing a bunch of aging Cisco 3550s.

My question...

We have traditionally used mirror ports in a L2 switch attached to a FreeBSD box 
with NICs in promisc. mode to do our traffic accounting (monitoring the traffic 
to/from the edge and ignoring local traffic).  However, with the new 6509 
platform, we are hoping to use NetFlow v9 instead and get rid of the sniffer 
box.  Our hope is that we can monitor each customer port (which is configured as 
a L3/routed port) and export only the flows to/from the edge to our collector, 
and then use that data for billing purposes.

My concern is that, due to our inexperience with the 6500 platform, I want to 
make sure we don't run into any performance issues or, worse yet, stability 
issues in IOS.  Any advice along these lines would be appreciated.

--Mike