[c-nsp] NetFlow for Bandwidth Billing

[Roland Dobbins]

On May 2, 2007, at 7:47 AM, Adam Powers wrote:

> 4. Verify that your cache timers are compatible with the collector’s
> measurement intervals. Else you’ll get a nasty sawtooth effect that
> customers won’t like.

Concur - generally, setting the active flow timeout value down to the  
minimum of 1 minute is a rule of thumb, unless one has other  
considerations which dictate a different interval.

>
> 5. Make sure you have a mechanism for detecting NetFlow outages.  
> This is
> more to protect you than the customer as they won’t mind at all if  
> your
> missing traffic for a few hours.

Along with this, it's a really good idea to export the NetFlow  
telemetry across a DCN/OOB management network if at all possible, so  
that network partition events don't render you blind.  And of course,  
ntp on all the exporters as well as the collection/analysis systems  
is key.

------------------------------------------------------------------------
Roland Dobbins <rdobbins at cisco.com> // 408.527.6376 voice

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