multihomed host issue

[Curtis Doty <Curtis --at-- GreenKey.net>]

I've not looked at the code yet. But here is an interesting situation I 
just discovered. If the server side of an iperf test is multi-homed. And 
I attempt to conduct a bidirectional test against the ip on a *far* side 
interface, it will error with a "write2 failed: Broken pipe" message on 
the server. The client will hang indefinitely. Apparently awaiting a 
socket from the server that never arrives.

Here is the obligatory ascii diagram:

client
 |
(wan)
 |
10.2.2.0
 |
server (10.2.2.1 and 10.3.3.1)
 |
10.3.3.0

Both hosts are linux. This will cause the bug:
client# iperf -c 10.3.3.1 -r

Whereas, this will work fine:
client# iperf -c 10.2.2.1 -r

I'm guessing there may be some sanity checks to prevent iperf servers 
from being exploited to direct connections to a 3rd party. But maybe 
they are too strict in the case of multi-homed boxes?

../C