in reply to Can't Break Out of SSH Shell

You have a socket open to a remote machine, and on the far side you take down the interface, before the program you're running on the far side exits. I'm not at all sure what that does with existing connections, and whether ssh will eventually time out. It certainly means that the packets to cleanly close the connection won't propogate from the remote sshd to the local ssh.

What happens when drop the remote interface from the (local) command line? Does ssh exit, or does it hang?

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Re: Re: Can't Break Out of SSH Shell
by dru145 (Friar) on Jun 08, 2001 at 08:41 UTC

    It hangs from the command line also. How about running something like: ps -ef | grep -v grep |grep "ssh 192.168.2.3" saving the results to a hash and then perform a kill on the pid? But can you spawn a new shell while waiting for the ssh connection to close? I let it site for about 5 minutes and it still isn't timing out.

[reply]
      If ssh also hangs from the shell, chances are good that the local TCP stack isn't seeing that the socket is closed (because it isn't, as far as the TCP stack is concerned, since no FIN packet ever arrives).

      Try rigging script on the far side that forks and exits in the parent process, while the child sleeps a few seconds and then drops the interface. When the parent process exits, sshd should close the socket.

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