NetFlow - path from Routers to Collector

Tue Sep 1 20:45:45 UTC 2015

Agree.  Most OOB is lacking redundancy too, so a single failure can really take the shine off an OOB deployment.  Especially when you've put your management traffic on it, including radius traffic, and you're using 802.1X.  Found that out the hard way a few years ago.  

Chuck

-----Original Message-----
From: NANOG [mailto:nanog-bounces at nanog.org] On Behalf Of Tarko Tikan
Sent: Tuesday, September 01, 2015 3:47 PM
To: nanog at nanog.org
Subject: Re: NetFlow - path from Routers to Collector

hey,

> It should've already been spent for an OOB/DCN network, which 
> should've been provisioned with flow telemetry in mind.

Bad advice. No amount of money will fix major platforms that are not happy to export flow telemetry via router management ports. Sometimes it can be done via nasty vrf leaking hacks, sometimes it cannot be done at all. Management ports are typically directly connected to routing engines while netflow data is generated in hardware in PFE.

In-band netflow works on all platforms without such issues.

--
tarko