Dropping SSH connections over the internet

[Hal Burgiss]

On Fri, Jan 11, 2008 at 10:32:27AM -0500, Luis Mondesi wrote:
> 
> The reason I know it's 2 different things is because we use 2
> different methods to connect to the same remote network. 1 from home
> over public internet (timeout). 2 from one office on one location over
> a private T1 going to a different router.

I'll add maybe a third scenario. I have at least six ssh sessions from
home (DSL service with Ubuntu OS) to work (various Linux) 24/7. Every
two or three days these all hang. Eventually, after maybe an hour I
get a message about the connection and the prompt comes back. I
can open another terminal and reconnect right away in the meantime or
even kill the comatose sessions and reconnect, so it is not a server
problem per se. 

I have had this happen while I am at the keyboard and it has almost
always been during bad weather, like storms anywhere in the area. Not
necessarily bad storms either, just some lightning here or there.
Keepalive settings don't seem to help at all. Not all the disconnects
are storm related, those are just the ones I have witnessed. My theory
is some kind of packet corruption that "scares" the sshd end into not
responding, and the connection dies because of tcp timeout. But just
a wild theory. I'd love to know answer myself.

-- 
Hal