automate getting diagnostic files from a controller via ssh commands - bash

I'd like to automate getting diagnostic files from a controller that responds to ssh commands, like e.g.
ssh diag#controller tarred > diags.tgz
Unfortunately, I have to type a password to make the above command go through.
What have I considered to get around that:
using ssh keys: not possible, since I can't login to the controller, it just expects commands and doesn't offer a shell
using ssh-pass package: I don't have admin rights on the machine and can't install packages
using "expect": works to some extent, but the resulting file is corrupted.
Here's the "expect" script I've used:
#!/usr/bin/expect -f
log_user 0
set timeout 300
spawn ssh diag#controller tarred
expect "?assword:"
send "unrealpassword\r"
expect \r\n
log_user 1
expect eof
The script makes sure that only the required output gets stored with the "log_user" commands until eof is encountered.
I've piped this script to a file and that file is corrupted, i.e. it's either too short (because of a timeout?) or too long (?).
Any idea about what goes wrong here.?

Related

How do you suppress the password prompts in expect scripts?

I'm trying to write a set of scripts, a main payload script that runs some commands over ssh and a small expect wrapper that runs it. (For sake of argument, please accept that I can't put my ssh keys on my target machines.)
The expect script runs fine, filling in the password when required. However, it also passes the prompt (user#machine's password:) through to stdout. I want to remove the matched prompts and only the matched prompts from the output. I still want the results of the remote scripts running, so log_user 0 is too broad.
Is there a way to do this?

Passing variable to Expect and Spawn

I'm writing a script that will scp a tar file from my local server to a remote host. Since the script generates the file through a pre-requisite process, the name is generated dynamically. My script needs to take the name of the file and pass it to scp for transfer.
#!/usr/bin/expect -f
spawn scp test.$(date +%y%m%d_%H%M).tar user#IP-ADDRESS:/destination/folder
set pass "password"
expect "password: "
send -- "$pass\r"
expect eof
I've tried setting the filename as a variable but keep seeing the same error:
can't read "(date +%y%m%d_%H%M)": no such variable
while executing "spawn scp test.$(date +%y%m%d_%H%M).tar user#IP-ADDRESS:/destination/folder"
$(date +%y%m%d_%H%M) is not a Tcl command. If you use expect, you have to learn Tcl. To get a formatted date in Tcl, use the clock command. Also, interpolation of the result from a command in Tcl is not done by $(....), but by [....]. You can find examples for this construct here.
Decided to go another route since the team was able to provision a new Artifactory repo for this binary and alike. However, to the advice provided here I was able to make a few discoveries which I used to fix my issues:
I also had a password with $ symbol and that also caused a world of issues.
#!/bin/bash
TEST=$(date +%y%m%d_%H%M)
/usr/bin/expect <<eof
set password {pas\$word}
spawn scp "$TEST" user#IP-ADDRESS:/destination/folder
expect "*password:"
send "$pasword\r"
expect eof

How to send commands stored in a file when using Expect

I'm writing a script that will eventually execute a list of commands on a switch (via SSH). These commands are stored in a file and the number of commands will vary
However, I'm not sure how this can be done using Expect. I know Expect can use a while loop, but I can't find a clear example. can someone here help?
/usr/bin/expect <<EOD
spawn ssh -o StrictHostKeyChecking=no admin#$switch
expect "*Enter password for admin\:"
send "password\r"
expect "*#"
send "????"
there should be a while loop that reads line by line from a file called "commands" that looks like this
command 1
command 2
command 3
...
Extreme Networks XOS has an XML API. You can use this for executing arbitrary commands. See the ExtremeXOS XML API Developer Guide which is listed on the support documentation page.
Managing switches by expect-scripting their CLIs is often erratic and error prone, I'd recommend that you avoid doing so if possible.

Writing strings to standard input in bash script

I'm trying to automate a startup of a specific service with bash
When the service is started with init.d (/etc/init.d/openvpn.custom) it is promting for username and then password - and then it connects
The auth-user-pass from-file is not possible with the installed version, and it cannot be upgraded because of dependencies
So i'm trying to write a simple bash scripts that executes the init.d script, sleeps for a bit, inputs the username, returns, sleeping a bit, inputting the password - you'll get the flow.
like http://pastebin.com/qWHX7Di5
I've experimented with echo, but it doesent seem to work
This is for a rather legacy firewall i'm asked to keep connected.
Is this even possible?
I would use expect instead of bash. You can still call it from within bash if you need to do other tasks as well.
In expect, the script would be something like the following (untested):
#!/usr/bin/expect -f
set username "username"
set password "password"
spawn /etc/init.d/openvpn.custom start
expect "Username:"
send "$username\r"
expect "Password:"
send "$password\r"
expect eof
You'd want to change the expect "Username:" & expect "Password:" lines to match the actual login prompts that are output by your init.d script.
See the expect man page for further details.
You can try using a here-doc:
/path/to/init.d << END
$username
$password
END

Problems with terminating connection after running scripts on remote computer using shell script

This is the first time I am writing a shell script. I tried to do as much research as I can to avoid dumb/repetitive question. Please excuse if its repeat/dumb question.
I have a shell script which connects to remote linux machine and runs scripts there. I am using 'expect' to spawn a ssh connection and to issue commands to trigger the job. However, I am having issues while closing the connection after completing the job.
This is my script:
set prompt "(%|#|\\$|%\]) $"
expect -c 'spawn ssh $UN#$STAGE ;
expect password ; send "$PASS \n";
expect -regexp "$PROMPT"; send "./settings.$UN.sh > settings_log.txt \n";
interact'
This script successfully runs the script file for me ($UN and $STAGE parameters are input to the script. I omitted that here for simplicity). However, this leaves me with an open connection.
I tried to close the connection after running the script by using following instead of above
expect -c 'spawn ssh $UN#$STAGE ;
expect password ; send "$PASS \n";
expect -regexp "$PROMPT"; send "./settings.$UN.sh > settings_log.txt \n";
expect -regexp "$PROMPT"; send "exit \n"'
This does close the connection but I noticed that my script file did not run at all. Also the settings_log.txt is not generated at all.
Does this mean, that exit command is aborting the process before its completion? I tried using 'sleep' before exit but it did not help. Is there a better suggested way to terminate the connection when using expect?
Any help is appreciated.
with expect, you terminate your send commands with \r not \n, so
expect -c 'spawn ssh $UN#$STAGE
expect password
send "$PASS\r"
expect -regexp "$PROMPT"
send "./settings.$UN.sh > settings_log.txt\r"
expect -regexp "$PROMPT"
send "exit\r"
expect eof'
Note you can execute remote shell commands and copy files using ssh and scp, directly, without using expect.
For example,
scp ./settings.$UN.sh $UN#$STAGE:settings_log.txt
ssh $UN#$STAGE whatever-you-need-to-execute
The connection will close as soon as soon as whatever-you-need-to-execute completes.
Your outer script seems to be written in csh and sets a variable named "prompt", but your expect script is using a variable called "PROMPT". Try making the two variable names match case.

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