keepalive message not sent?

[Fabrizio Bertocci]

Hi All,
Here is an interesting (but inconvenient) problem I've found with dbclient
when connected to an OpenSSH server that uses the keepalive
(ClientAliveInterval & ClientAliveCountMax).

I have a OpenSSH server that sends keepalive messages to the client every 10
seconds and consider the client disconnected after 2 failed attempts.

On my client I use dbclient (latest version 0.52) to start a connection
(using a private key with no password) to setup some tunnels (local &
remote).
So far so good. When I launch the dbclient from a shell everything is fine,
this is what I see on the server log every 10 seconds:

debug2: channel 1: request keepalive at openssh.com confirm 1
debug1: Got 100/10 for keepalive
debug2: channel 1: request keepalive at openssh.com confirm 1
debug1: Got 100/11 for keepalive
...
and the server keep maintaining the connection with the client.

Unfortunately, when I invoke my bourne shell script (that I use as wrapper
for launching dbclient) from the init script (/etc/init.d/myWrapper.sh),
everything SEEMS to work fine, but when the server sends keep alive
messages, the dbclient doesn't seem to respond correctly.
This is what I see from the server's log:

debug2: channel 1: request keepalive at openssh.com confirm 1
debug2: channel 1: almost dead
debug2: channel 1: gc: notify user
debug1: session_by_channel: session 0 channel 1
debug1: session_close_by_channel: channel 1 child 18881
debug1: session_close_by_channel: channel 1: has child
...
Disconnecting: Timeout, your session not responding.
debug1: do_cleanup
debug1: do_cleanup

Does anybody have an idea why ?
It has something to do with I/O probably or some settings that are available
when I launch my script (or the dbclient) from an interactive session but is
missing when is invoked from the init script...

Regards,
fabrizio
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