Good EXPECT script to use on Cisco / Other Network Devices

Expect script is a great way to make config changes across 40 or more switches/routers in your company without telnet or ssh into each device.

The script can be modified to suit your needs.  I modified Paul's http://paulgporter.net/2012/12/08/30/comment-page-1/#comment-1703 script to meet my needs.

SSH for EXPECT is at the end. Below is for TELNET EXPECT:

STEPS:

1. Install EXPECT on your CENTOS or linux box
    yum install expect
        - The expect command should be installed in /usr/bin/expect. 

Create your expect script:

2.  Make a text file and put all IP Addresses of your devices:
    [root@localhost script]# vi device-list

172.x.x.1
172.x.x.2
172.x.x.3
etc.

3. Create expectrun.sh file and put the following in it:

[root@localhost script]# vi expectrun.sh

#!/bin/bash

# Collect the current user's ssh and enable passwords
echo -n "Enter the SSH password for YOURUSERNAME"
read -s -e password
echo -ne '\n'
echo -n "Enter the Enable password for YOURUSERNAME"
read -s -e enable
echo -ne '\n'

# Set terminal to vt100 so Nexus devices don't complain
export TERM=vt100

# Feed the expect script a device list & the collected passwords
for device in `cat device-list`; do
./expectscript.exp $device $password $enable ;
done


4. Create the "EXPECT" script called, expectscript.exp and put the following:

[root@localhost script]# vi expectscript.exp

#!/usr/bin/expect

# Set variables
 set hostname [lindex $argv 0]
 set username "YOURUSERNAME"
 set password [lindex $argv 1]
 set enablepassword [lindex $argv 2]

# Path to Where to put the Log file results
 log_file -a /root/script/results.log

# Display the device we are working on and the time
 send_user "\n"
 send_user ">>>>>  Working on $hostname @ [exec date] <<<<<\n"
 send_user "\n"

# Telnet
#spawn telnet $hostname
#expect "Username: " sleep .1;
#send "$username\r";
#sleep .1;
#expect "Password:"
#send "$password\r";

# Telnet
spawn telnet $hostname
expect "Username: "
send "$username\r"
expect "*assword: "
send "$password\r"

# Check to see if we're already in enable mode, if not get us there
 expect {
 default { send_user "\nEnable Mode Failed - Check Password\n"; exit 1 }
 "*#" {}
 "*>" {
 send "enable\n"
 expect "*assword"
 send "$enablepassword\n"
 expect "*#"
 }
 }

# Let's GET into configure mode
 send "conf t\n"
 expect "(config)#"

# Enter your commands here. Examples listed below
 send "aaa authorization commands 1 default  group tacacs+ local \n"
 expect "(config)#"
 send "aaa authorization commands 15 default group tacacs+ local \n"
 expect "(config)#"
 send "aaa authorization config-commands \n"
 expect "(config)#"
 #send "service timestamps log datetime msec localtime\n"
 #expect "(config)#"
 #send "clock timezone PST -8\n"
 #expect "(config)#"
 #send "clock summer-time PDT recurring\n"
 #expect "(config)#"
 #send "service timestamps debug datetime msec localtime\n"
 #expect "(config)#"

 send "end\n"
 expect "#"
 send "write mem\n"
 expect "#"
 send "exit\n"
 expect ":~\$"
 exit

5. Now RUN the expectrun.sh script:
    [root@localhost script]# ./expectrun.sh

========================

NOTE:  FOR SSH to devices instead of using telnet:
The Cisco IOS image used must be a k9(crypto) image in order to support SSH. For example c3750e-universalk9-mz.150-1.SE2.bin is a k9 (crypto) image.

[root@localhost script]# vi expectscript.exp

DELETE THE TELNET REFERENCE:

# Telnet
spawn telnet $hostname
expect "Username: "
send "$username\r"
expect "*assword: "
send "$password\r"

ADD the following for SSH to WORK:

# For SSH to devices and don't check keys
 spawn ssh -o StrictHostKeyChecking=no $username\@$hostname

# Need to SSH to Work. Allow script to handle ssh connection issues
 expect {
 timeout { send_user "\nTimeout Exceeded - Check Host\n"; exit 1 }
 eof { send_user "\nSSH Connection To $hostname Failed\n"; exit 1 }
 "*#" {}
 "*assword:" {
 send "$password\n"
 }
 }

THAT'S IT.