ssh: how to make it drop the connection when it is not connected?

john_owens_at_yahoo.com
Date: 08/20/04

  • Next message: Ray: "Re: ssh issue?" 
    Date: 19 Aug 2004 16:24:31 -0700

    I've set up a ssh tunnel that runs at startup so that I can send mail
    when I'm off-campus:

    #!/bin/sh
    # http://cg.scs.carleton.ca/~morin/misc/laptopmail/

    . /etc/rc.common

    ConsoleMessage "Starting smtptunnel"
    while [ 1 ]; do
    ssh -N -L25:mailserver:25 username@mailserver
    sleep 5
    done

    The loop should make it maintain the connection when it drops.
    Unfortunately, when it is set up and then I lose network connectivity
    (sleeping my machine and waking it back up, or leaving wireless range),
    it doesn't drop the connection; instead it maintains some sort of
    zombie connection.

    When the connection works properly, I can do the following:

    % telnet localhost 25
    Trying ::1...
    Connected to localhost.
    Escape character is '^]'.
    220 mailhost ESMTP Sendmail 8.12.11/8.12.11; Wed, 18 Aug 2004 18:\00:36
    -0700
    ^]
    telnet> close

    But when I don't have connectivity, the tunnel still appears to be
    active (even though it can't connect):

    % telnet localhost 25
    Trying ::1...
    Connected to localhost.
    Escape character is '^]'.
    ^]
    telnet> close

    What I really want is when the ssh tunnel is not "connected" (cannot
    find its destination) then it ends; right now it is just a zombie
    connection, and I have to manually kill it and restart when I get back
    into network range.

    Suggestions?

    (OS X 10.3.5, OpenSSH_3.6.1p1+CAN-2003-0693, SSH protocols 1.5/2.0,
    OpenSSL 0x0090702f)

    JDO

  • Next message: Ray: "Re: ssh issue?"

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