On Sun, Feb 26, 2012 at 3:18 PM, Frank Cox theatre@melvilletheatre.com wrote:
Without separate interfaces there's not much to distinguish your local/external concepts.
As I see it, there's probably some way (that I haven't yet discovered) to separate the traffic by gateway. Or at least some way to distinguish local traffic from external traffic.
There is, but not in the places that normal metrics are gathered. You need to look at the route toward the target IP address for your breakdown. There are tools to do it in iptables, but it is not a common operation so you are probably on your own to set up the matches and read the counters. Someone doing it on a larger scale would probably arrange subnets to isolate the traffic by interfaces or use routers with netflow metrics to track usage by connection.