ssh ServerAlive probes

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Hello,

I am working on an application that needs to be able to rapidly detect a =

lost connection between an ssh client and ssh server.  I am using ssh to =

do local and remote port forwarding, and sending data across the=20
forwarded ports.  I was originally relying upon the TCPKeepAlive probes, =

but found that I could not consistently detect a lost detection.  Using=20
the ServerAliveInterval and ServerAliveCountMax options, however, I am=20
able to consistently detect a lost connection.  The problem is, if I am=20
using a low-bandwidth connection (cellular modem), and I am pushing a=20
significant amount of data across, it seems that this hinders the=20
communication between the client and server with the ServerAlive=20
messages.  In other words, when I am actually USING the connection, my=20
application can mistakenly detect the connection as lost because the=20
ServerAliveInterval x ServerAliveCountMax is exceeded without a response =

from the server.  I was surprised at this behavior, since I expected the =

ServerAlive probes to only start after data flow between the client and=20
server machines across that connection had ceased, but perhaps I am=20
misunderstanding.  I do not have much leeway as to how the server is=20
configured.  Can someone recommend a way to be able to both (1) quickly=20
detect a lost connection [which, seems to require the interval and=20
countmax be small], but not mistakenly detect the connection as lost=20
when it is being used?

Thank you for any assistance.

Don




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