Script to get info from multiple servers - bash

Question

I want to collect info from a number of servers whether their grub.conf contains the "elevator" parameter or not.
Now, password-less key authentication is something I can not do as of now. I am okay with specifying password in script.
Can someone please help me achieving this?
This is what I did:
#!/bin/bash
GRUB="/etc/grub.conf"
_pair="$(</home/wadhwaso/login.txt)"
Server_info="/tmp/server_info"
for e in $_pair
do
# extract user and ips for each $e in $_pair
IFS='#'
set -- $e
_user="$1"
_ip="$2"
sleep 2
echo "Connecting to server '${_ip}' via SSH..."
ssh ${_user}#${_ip} "sudo grep -q "elevator=noop" "$GRUB" >/dev/null"
if [ $? -eq 0 ]; then
echo "Present on ${_ip}" | tee -a "${Server_info}"
else
echo "not present on ${_ip}" | tee -a "${Server_info}"
fi
done
I don't want to give password every time, and as password-less authentication is not present in my environment and will not be possible, I have to pass the password in script itself which really doesn't bother me, I can do that. I know it could be done through expect but I messed everything every time I tried using it.
I tried using expect the way it was told in 1st answer but I failed.

Answer 1

The "expect" tool sounds perfect for what you need: http://expect.sourceforge.net/
To install expect (on ubuntu, for example), do:
sudo apt-get install expect
Here's a code snippet showing you how to use expect as part of a bash script:
#!/bin/bash
IP="111.111.11.1"
login="root"
password="some_password"
dest_dir="/etc/"
expect_sh=$(expect -c "
spawn ssh $login#$IP
expect \"password:\"
send \"$password\r\"
expect \"#\"
send \"cd $dest_dir\r\"
expect \"#\"
send \"chmod +x $server_side_script"
expect \"#\"
send \"./$server_side_script\r\"
expect \"#\"
send \"cd /lib\r\"
send \"cat $file_count\r\"
expect \"#\"
send \"exit\r\"
")
echo "$expect_sh"
Alternatively, you can put the logic in a separate expect script for neater syntax and source it from your bash script:
#!/usr/bin/expect
set login "root"
set addr "111.111.1.1"
set pw "root"
spawn ssh $login#$addr
expect "$login#$addr\'s password:"
send "$pw\r"
expect "#"
send "cd /etc\r"
# Then other things you need to do
As for the "3rd thing" with RSA key fingerprint: SSH will warn you if connecting to a host you haven't seen before (because of possibility of man-in-the-middle attacks), theoretically you should verify that the fingerprint matches what you anticipate it to be to verify that the host is who the host claims to be.
Hope this helps =)