Usage Graphing per Subnet

[streiner at cluebyfour.org (Justin M. Streiner)]

On Wed, 18 Feb 2015, Methsri Wickramarathna wrote:

> My company has 3 upstream providers and we are serving more than 400
> customers ..In that case we have to manage our upstream capacity... When
> considering capacity managing normally we just transfer a  /24 from
> congested Up stream provider to non congested provider.
> Issue we have is we don't know exactly the usage of a /24 subnet before
> transfer.

Netflow/sflow/IPFIX is most likely going to be the easiest/cleanest way to 
get the data you want.

I would also recommend announcing a consistent set of prefixes to all 3 
providers, and using mechanisms like AS-PATH prepending and/or whatever 
BGP communities each provider offers to do things like tweak preferences 
or do selective prepending, rather than shuffling prefixes between 
providers to achieve some level of traffic engineering, and also keeping 
your announcements aggregated as much as possible.  Less routing table 
bloat and churn is a good thing.

jms