The option of ipappend 1 in the default file and retransmission
of HELLOs in udp-sender (--rexmit-hello-interval) has been
valuable to getting udpcast working with the Dell notebooks
we have with Broadcom 5700 series ethernet.
Today, with a slightly newer broadcom chipset appearing in
the most recent shipment, we noticed that udp-receiver was
intermittantly not showing the "hit any button to start transfer"
message. With some trial and error I found that if I
watched the tail of /var/log/message on the receiver (server)
and waited for the messages on TX and RX flow control to
complete before running udp-receiver, it would always initiate
a good connection. If I had started the udp-receiver
prior to the TX/RX flow control appearing in the message log
(in which case there was no "hit any key" message),
I could ^C the receiver, run it again and it would signify
the ready state with 100% success.
In conclusion, we have a workaround of starting udp-receiver
after a few seconds past the client PXE machine booting and
showing the udp-sender status ready (but not yet "hit any key...").
Another solution would be if udp-receiver also supported
--rexmit-hello-interval. It isn't a flaw in the udpcast system
but a kludge for a network device that is proving itself to be
sluggish in initialization in general.