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Hey, all.  We're trying to track down some UDP fragmentation issues, and 
I'm trying to fully grasp exactly what goes on.  The tool I'm using is 
"iperf."  My first confusion is that when I point iperf (client) to a 
host behind a floating IP, that simply doesn't work.  Any ideas what the 
issue is, and how to get around it?

Next up is this that when I have to VMs talk to each other -- on the 
same subnet, using "iperf -c 172.23.244.169 -u -b 100m" -- I wind up 
with this:
[  3] Sent 85471 datagrams
[  3] WARNING: did not receive ack of last datagram after 10 tries.

When I go from physical machine to physical machine, it works great, 
even though a few datagrams are received out-of-order.  But a flat-out 
missing packet does sound a bit like the issue I'm having.

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Additionally, I'd really like a tool that would allow me to set packet 
size for UDP tests; I've poked around, but haven't really found 
anything.  If anyone has a suggestion, I'm all ears.

Thanks!

-Ken