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 <rdobb...@arbor.net>