Я нашел маленький util названным portfwd http://portfwd.sourceforge.net/, он делает точно, в чем я нуждаюсь (TCP и передача UDP), домашняя страница говорит, что он обновился в 2002, но последний выпуск является 2007, и он работает над 2,6 ядрами.
For anyone interested in an update:
I have since does some testing on a couple of test virtual box instances.
I setup the OpenVPN between the two, same as in the real setup.
I setup the gluster volumes in the same way, and it all works.
I tried to replicate the exact steps on the real environment and it does not.
It seems to be a tuning issue on the OpenVZ containers, and I have opened a couple of support tickets with them requesting certain tuning parameters I found on another post.
I will update this thread once I have confirmed whether that tuning does or does not work.
J