SSH connection closes as shell fails to load

Question

I have FreeBSd running with OpenSSH. I set up everything and the connection via SSH worked perfectly. Then I decided to get rid of some not used ports and I obviously uninstalled one that was used by zsh.

When I log in I get the following:

~ # ssh [email protected]
Password:
Last login: Wed Nov  7 21:56:26 2012 from 192.168.1.52
FreeBSD 9.0-RELEASE (GENERIC) #0: Tue Jan  3 07:15:25 UTC 2012

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Edit /etc/motd to change this login announcement.

Shared object "libiconv.so.3" not found, required by "zsh"Connection to 192.168.1.56 closed.

The thing is that I have no monitor nor do I have a keyboard (right now) to solve the problem very quickly...

I tried this to force loading a different shell > Force SSH to use a specific shell

Does not work as I get:

~ # ssh [email protected] /usr/local/bin/sh << EOF
chsh -s /usr/local/bin/bash
EOF
Password:
Shared object "libiconv.so.3" not found, required by "zsh"%    

Any ideas how to solve it without keyboard and monitor?

Answer 1

I did this same exact error once. I doubt you'll be able to get the root access needed to change your shell remotely. Another, less likely option is to hack your own box and get root privileges.

I had to connect locally via keyboard and monitor and change to the default shell. Never make root use a userland shell. Always let root use the default shell that comes with the system. If you need or want to use a different shell, start it manually after login. This is what I do now.

And remember, don't do make delete-old-libs in /usr/src unless you absolutely know you won't be needing those libs anymore :-D

Answer 2

If sftp works, I would try to upload a ~/.ssh/rc file with the commands I need to run (perhaps echo password | chsh -s /usr/local/bin/bash?) and hope that ssh, as its manual page states, does execute those commands before launching the user's shell.

Answer 3

Method 1

Try following

    ssh username@hostname "/bin/sh -i"

That will let you login with sh instead of bash if successful.

Method 2

ssh into the box with another user and then su/sudo to regain root access.

Answer 4

bash and zsh both have a dependency on libiconv, so neither will work for you, since you removed it. You can do as John suggested, and tell ssh explicitly to run sh or csh, which are both in the base system and should therefore function correctly, as they have no external dependency on anything in ports.

ssh me@there "/bin/sh -i"

You now have a shell session, where you can install libiconv again. For future reference, it's worth using something like ports-mgmt/pkg_cutleaves to remove ports you no longer need - it makes it much harder to shoot yourself in the foot like this!