Thanks for the many answers to my initial request:
https://lists.fedoraproject.org/pipermail/users/2015-October/465783.html
which I am only reading NOW, in the list archives, because...
I had wrongly flagged my own message and all its replies as spam :-(
(long story for another day).
Anyway: I will try the suggestions below over the weekend, and report
next week:
KeepAlive yes
TCPKeepAlive yes
ServerAliveCountMax 3
ServerAliveInterval 17
hopefully it should be enough. I also not use reverse port forward, on
those
servers. I'll let you know how it goes.
Thanks,
Marco
--
http://mfioretti.com