[netflow-tools] unable to export flows

[Damien Miller]

On Tue, 27 Mar 2007, memic wrote:

> no, the export is working, but i get those errors from time to time..
> 
> Cristian KLEIN wrote:
> > memic wrote:
> >   
> >> hi,
> >>
> >> i get those strange messages in my syslog
> >>
> >> Mar 26 16:37:24 bgp softflowd[10249]: Unable to export flows
> >> Mar 26 16:37:28 bgp last message repeated 3 times
> >> Mar 26 16:39:28 bgp last message repeated 4 times
> >>
> >> ideas where they come from?
> >>     
> >
> > Is it possible that your firewall disallows outgoing UDP for your flows?
> > Try enabling verbosity.

This message can occur in a couple of cases, the two that spring to mind are:

1. UDP socket send buffer is full. softflowd may benefit from an increase
   of the send buffer, similar to the change I made to flowd:
   http://cvsweb.mindrot.org/index.cgi/flowd/privsep.c.diff?r1=1.29;r2=1.30
   (patches welcome)

2. ICMP unreachable errors from the export target host or intervening 
   gateways -- there isn't much softflowd can do in this case.

-d