I have two networks and a static route between them. When I try to connect to a server (with ssh) from one of the networks to the other (the connections goes through the static route) the connection times out.
Everything else works just fine with this static route.
A few months ago I had a similar issue and setting UsePAM to yes resolved it. I don't know why but it worked on a default Ubuntu Server 16.04.
Now I have the same problem but only activating UsePAM doesn't resolve it. I can reproduce the issue on a raspberry pi ssh server (raspbian stretch) and on a default mac ssh server. UsePAM is enabled in both cases.
I guess there is another configuration option which prevents the ssh connection to be established correctly. Maybe not even a ssh config option.
How can I resolve this issue and allow ssh connections through static routes?
