Ssh, run a command on login, and then Stay Logged In?

Question

I tried this with expect, but it didn't work: it closed the connection at the end.

Can we run a script via ssh which will log into remote machines, run a command, and not disconnect?

So ssh in a machine, cd to such and such a directory, and then run a command, and stay logged in.

-Jonathan

(expect I used)

#!/usr/bin/expect -f
set password [lrange $argv 0 0]
spawn ssh root@marlboro "cd /tmp; ls -altr | tail"
expect "?assword:*"
send -- "$password\r"
send -- "\r"
interact

Answer 1

Add a ; /bin/bash to the end of your command line on the remote side? That is:

spawn ssh root@marlboro "cd /tmp; ls -altr | tail; /bin/bash -i"

Even better, change root's .bashrc to be something like this:

PROMPT_COMMAND="cd /tmp && ls -altr | tail ; unset PROMPT_COMMAND"

:)

Answer 2

If you are ok with doing this in Python, pexpect has an example that does almost exactly what you are asking for:

import pexpect
child = pexpect.spawn ('ftp ftp.openbsd.org')
child.expect ('Name .*: ')
child.sendline ('anonymous')
child.expect ('Password:')
child.sendline ('noah@example.com')
child.expect ('ftp> ')
child.sendline ('ls /pub/OpenBSD/')
child.expect ('ftp> ')
print child.before   # Print the result of the ls command.
child.interact()     # Give control of the child to the user.

To do this with ssh instead of ftp, you'd want code similar to the following (the example files in pexpect have much more details and info, but here are the basics):

import pexpect
child = pexpect.spawn ('ssh root@marlboro')
child.expect ('Password:')
child.sendline ('password')
child.expect ('prompt# ')
child.sendline ('cd /tmp')
child.expect ('prompt# ')
child.sendline ('ls -altr | tail')
child.expect ('prompt# ')
print child.before, child.after   # Print the result of the ls command.
child.interact()     # Give control of the child to the user.

Don't get me wrong, I LOVE expect (especially autoexpect), but python is just soooo much easier for me to grok.

Answer 3

You should generally avoid using ssh in this kind of way as it defeats it's purpose.
Do an

ssh-add -l | grep "file_of_your_rsa_priv_key_here"

to see if your key is listed in the ssh active session pool or else add it yourself (with ssh-add).