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I am scratching my head here. I now get timeouts between hosts A and B, both running Ubuntu, with some firewall NATing on either side and a good dozen hops in between. (To clarify based on the first comment: The initial connection fails and 'hangs'; this may be after another (existing) connection ended.)

Yet I can also connect using ssh from A to another host on another subnet, call it C and then connect from C to B just fine. So it should not be the ssh server settings. The alternate route also works for a second host D, also on another subnet.

But the trouble is that my main workstation often just sits there when trying to connect. The only related issue I can think of is that I am also (sometimes) using sshfs between A and B.

One idea as to how I can address this?

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Do you mean a timeout as in it doesn't connect, or a timeout in that the connection stops after working for a while? – Paul Dec 28 '11 at 22:58
I am more concerned about the former. It just sits there at about line 4 under ssh -v and nothing happens. Whereas I can go the alternate route. The odd thing is that the timeout seems to affect all possibly clients on my home network. Yet I had the same NAT setup for many years. – Dirk Eddelbuettel Dec 28 '11 at 23:01
Is your IP static? Could it have been blocked on the server? – Paul Dec 28 '11 at 23:03
No, and "eventually" this resolves after maybe 20 or so minutes. But I do not recall adding a configuration on either side that would enforce this behaviour. – Dirk Eddelbuettel Dec 28 '11 at 23:06
Hmm, I wonder how far it is getting. Can you do a sudo traceroute -P tcp -p 22 <server B IP> – Paul Dec 29 '11 at 7:26

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