I have a script that helps me update the IOS of my Cisco devices when ever I need to. It works fine and I have no issues with the script itself other then the fact that it only does one device at a time.
Is there something that I can research to make the script run asymmetrically so it can do multiple sessions at one time?
The script consists of an expect script which is setup like so:
set timeout 6
set hostname [lindex argv $0]
set password [lindex argv $1]
spawn ssh $hostname
expect "TACACS*:"
send "$password\r"
expect "#"
send "term length 0\r"
< other similar commands >
interact
The main bash script works as follows:
IP=$(cat ./iphosts)
read -p "Please enter your TACACS Password:" password
for i in $IP
do
expect 01.exp $i $password | tee -a bulk.log
done
interact
Both the expect and .sh script have a little bit more to each but those usually post script completion tasks like reporting or additional commands.
Thank you for any information that you can provide on this!
You can use the xargs tool to start a number of processes in parallel. For example:
#!/bin/sh
read -p "Please enter your TACACS Password:" password
xargs -IADDRESS -P4 expect 01.exp ADDRESS $password < ./iphosts
This uses the -P argument to xargs to run up to 4 processes at a time. You could scale up the argument to -P to run more processes in parallel.
But there's a problem here: you're calling interact in your expect script, which suggests that the script is expecting (possibly requires) interactive input from you when it is running. If this is the case, the solution presented here won't work. You would need to rewrite your expect script so that it does not require any user interaction.
You may also want to investigate a tool like Ansible which (a) does this sort of parallel execution by default and (b) has explicit support for configuring a variety of network devices.
Related
I'm writing a script that will scp a tar file from my local server to a remote host. Since the script generates the file through a pre-requisite process, the name is generated dynamically. My script needs to take the name of the file and pass it to scp for transfer.
#!/usr/bin/expect -f
spawn scp test.$(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
I want to use shell and expect to log in to the server with only one command.
But when interact and return are used in one statement, I don't understand what they mean.In addition, "Password" will only appear when SSH link multiplexing is disconnected, so I hope that when "Password" does not appear, it will not send "mypassord".
So how to write scripts to deal with these two situations in a unified way?
When SSH multiplexed links were established, my script was stuck in "expect "Password"".How to deal with it?
In addition, I would like to ask what does the -o parameter mean after the interact? And what is the meaning of using interact and return together?
What's the difference between "send --" and "send "?
I have enabled SSH master connection. Before I log on to the server, I need to first enter the password, and then enter a number to represent which machine I log on to. But when SSH multiplexed links are established, the option of entering passwords becomes redundant.
#!/usr/bin/expect
# ssh command
set cmd [lindex $argv 0]
set relay_num [lindex $argv 1]
set timeout -1
# run ssh command
spawn bash -c "$cmd"
expect "Password*"
send "mypassord\r"
interact -o -nobuffer -re "Option" return
send -- "$relay_num\r"
interact
In combination with the -o switch, that line is looking at the output of the command for the regex "Option". The return will cause the interact command to end and the script continues to the send command (that is explained in the man page).
I think it would be more clear to use expect "Option" instead.
I'm working on a small project for school. I'm using 15 or so tuners to emulate a Cell network. I'm by no means well versed in scripting yet. I'm an EE who usually googles until I have some frankencode capable of my purposes.
The goal is the set up all the modules quickly so I thought to automate the process with a script. This requires ssh, and so far I have to manually type in the password each time. This morning I set up a basic test with both Expect and sshpass. In either case I can correctly log in, but not give instructions to the remote machine.
I was reading that sshpass has difficulty with sending remote instruction, correct me if I'm wrong.
/usr/bin/expect << EOF
spawn ssh root#<IP>
expect "(yes/no)?" #Are you sure you want to connect nonsense
send "yes\r"
expect "password"
send "$pass\r"
I tried a few things here to get the device to receive instruction
interact
cat /pathto/config.txt
#or
send "cat /pathto/config.txt
#the real goal is to send this instruction
sqlite3 /database.db "update table set param=X"
EOF
You might as well make it an expect script, not a shell script
#!/usr/bin/expect -f
and then pass the IP address to the script as a command line argument
expect myloginscript.exp 128.0.0.1 the_password
In the expect script, you'll grab that IP address from the arguments list
set ip [lindex $argv 0]
set pass [lindex $argv 1]
(Putting the password on the command line is not good security practice. You can research better methods of passing the password to your expect script.)
To use ssh, you'll be asked "are you sure" only the first time to connect, so let's make that conditional. That is done by letting the expect command wait for several patterns:
spawn ssh root#$ip
expect {
"(yes/no)?" {
send "yes\r"
# continue to wait for the password prompt
exp_continue
}
"password" {
send "$pass\r"
}
}
Once that is sent, you should expect to see your shell prompt. The pattern for this is up to your own configuration but it typically ends with a hash and a space.
expect -re {# $}
Now you can automate the rest of the commands:
send "cat /pathto/config.txt\r"
expect -re {# $}
# note the quoting
send "sqlite3 /database.db \"update table set param='X'\"\r"
expect -re {# $}
At this point, you'll want to log off:
send "exit\r"
expect eof
On the other hand, if you set up ssh private key authentication (see ssh-keygen and ssh-copy-id), you can just do this:
ssh root#IP sqlite3 /database.db "update table set param='$X'"
and not have to get into expect at all.
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
$password
END
This question already has answers here:
Using expect to pass a password to ssh
(6 answers)
Closed 5 years ago.
So I wanted to automate my SSH logins. The host I'm with doesn't allow key authentication on this server, so I had to be more inventive.
I don't know much about shell scripting, but some research showed me the command 'expect' and some scripts using it for exactly this purpose. I set up a script and ran it, it worked perfectly to login.
#!/usr/bin/env expect -f
set password "my_password"
match_max 1000
spawn ssh -p 2222 "my_username"#11.22.11.22
expect "*?assword:*"
send -- "$password\r"
send -- "\r"
expect eof
Initially, it runs as it should.
Last login: Wed May 12 21:07:52 on ttys002
esther:~ user$ expect expect-test.exp
spawn ssh -p 2222 my_username#11.22.11.22
my_username#11.22.11.22's password:
Last login: Wed May 12 15:44:43 2010 from 20.10.20.10
-jailshell-3.2$
But that's where the success ends.
Commands do not work, but hitting enter just makes a new line.
Arrow keys and other non-alphanumeric keys produce symbols like '^[[C', '^[[A', '^[OQ' etc.[1]
No other prompt appears except the two initially created by the expect script.
Any ignored commands will be executed by my local shell once expect times out.
An example:
-jailshell-3.2$ whoami
ls
pwd
hostname
(...time passes, expect times out...)
esther:~ user$ whoami
user
esther:~ ciaran$ ls
Books Documents Movies Public
Code Downloads Music Sites
Desktop Library Pictures expect-test.exp
esther:~ ciaran$ pwd
/Users/ciaran
esther:~ ciaran$ hostname
esther.local
As I said, I have no shell scripting experience, but I think it's being caused because I'm still "inside of" expect, but not "inside of" SSH. Is there any way to terminate expect once I've logged in, and have it hand over the SSH session to me?
I've tried commands like 'close' and 'exit', after " send -- "\r" ". Yeah, they do what I want and expect dies, but it vindictively takes the SSH session down with it, leaving me back where I started. What I really need is for expect to do its job and terminate, leaving the SSH session back in my hands as if I did it manually.
All help is appreciated, thanks.
[1] I know there's a name for this, but I don't know what it is. And this is one of those frightening things which can't be googled, because the punctuation characters are ignored. As a side question, what's the story here?
I think your problem has been solved here before:
Using expect to pass a password to ssh
The command you're looking for is interact. It hands the control over to you/your keyboard.
I've used a similar script to autologin.
I used "interact" and I removed "expect eof". By doing this, I can get the screen back so that I can enter commands by hand.
expect "?assword: "
send -- "$password\r"
expect "$"
interact
putting it all together, log you in and leave you on the command line exactly as though you typed it manually
#!/usr/bin/expect -f
set ip "127.001.001.001"
set password "xxyykkx"
spawn ssh $ip -l root
expect "?assword:"
send "$password\r"
interact