On 2 Sep 2015, at 5:49, Jared Mauch wrote:
Other platforms (e.g.: IOS-XR based) have issues with the MgmtEther interfaces which make them inoperable for many use-cases.
I'm agreeing with you. Dedicated management ports on many boxes don't actually support important management-plane functions, like flow telemetry - which is nuts, but that's what happens.
There are many technical details that are easily overlooked by those not using the routers to their abilities, so a small network (as Wes mentioned before with 2500s/T1s) still as OOB is unlikely to see data rates comparable to what is seen from a large router exporting data from hundreds of gigs of flows.
That's true. I understand that even on large networks, the OOB/DCN is built from old, grandfathered equipment. I spend a lot of time helping network operators calculate optimal flow sampling rates, flow cache sizes, etc., and an important consideration in making optimal configuration choices is what the OOB/DCN network can handle.
Often net flow vendors tell customers things that create more flow records which equals slightly higher data resolution but no actual net difference in results except for the lowest of bitrates.
Concur 100%. I spend a non-trivial amount of time talking folks down from the assumption that unnecessarily-low flow sampling ratios are required (these are mainly 'security' folks, not network engineers). ----------------------------------- Roland Dobbins <rdobbins@arbor.net>