Hello, I'm trying to do some telnet/ssh (start with telnet for simplicity) screen scraping from a Juniper switch (netconf/snmp aren't available) using the Expect.pm perl module.

My goal is to be able to shove the output of a few commands into an array for each command. For example:

"show version" goes to @show_version and "show interfaces" goes to @show_interfaces

I've consulted http://search.cpan.org/~rgiersig/Expect-1.15/Expect.pod#NAME

I am failing utterly at this.

I can login to the switch and do a basic command and then wait for the session to timeout.

I've tried various combinations but I've so far failed at:

1. Understanding the flow control logic of the Expect module. So to figure out I'm logged in, I need to look for a CLI prompt. But how do I tell the difference between the initial login vs. subsequent prompts (after the successful completion of a CLI command)?

2. How do I piggy back several show commands together without logging out each time? I see that as part of the module's FAQ (How to expect on multiple spawned commands) where it mentions the -i parameter but I just don't get it. 

#!/usr/bin/perl 

use strict;
use warnings;
use Expect;

my $cmd1 = "show version | no-more ";
 
my $access_protocol   = 'telnet';
my $router            = '172.16.2.1';
my $expect_log_file   = 'expect-log-file.txt';
my $timeout           = 15;
my $username          = 'username1';
my $password          = 'asdfasdfasdf';

#Uncomment to hide stdout:
#$Expect::Log_Stdout = 0;

my $exp = Expect->spawn("$access_protocol $router") or die "Can't conn
+ect to $router: $!\n";

$exp->expect  ($timeout,
  ['(yes/no)',sub{my $fh = shift; $fh->send("yes\n"); exp_continue;}],
  ['(sername: )|(ogin: )$',sub{my $fh = shift; $fh->send("$username\n"
+); exp_continue;}],
  ['(assword:)$',sub{my $fh = shift; $fh->send("$password\n"); exp_con
+tinue;}],             
  ['timeout',sub{&login_error();}],
  '-re', '> $', #wait for router prompt, then exit expect
                                                                      
+                                              );
$exp->log_file($expect_log_file);                                     
+                                   
$exp->expect  ($timeout,
  ['',sub{my $fh = shift; $fh->send("$cmd1 \n");}]
                                                                      
+                                              );    

$exp->expect  ($timeout,
  ['More',sub{my $fh = shift; $fh->send(" "); exp_continue}],
  '-re', '[#>:]$', #wait for router prompt, then exit expect,
                                                                      
+                                              );
$exp->expect  ($timeout,
  ['',sub{my $fh = shift; $fh->send("exit \n");}]
                                                                      
+                                              );
                                                                      
+                                              
sub login_error {
  print "Unable to login to router $router.  Try to login manually wit
+h SSH. \n";
  exit;
}

[download]
perl ./exp_1.pl
Trying 172.16.2.1...
Connected to 172.16.2.1 (172.16.2.1).
Escape character is '^]'.

EX3200-J (ttyp1)

login: username1
Password:

--- JUNOS 12.3R6.6 built 2014-03-13 06:58:47 UTC
username1@EX3200-J> show version | no-more 
Hostname: EX3200-J
Model: ex3200-24t
JUNOS Base OS boot [12.3R6.6]
JUNOS Base OS Software Suite [12.3R6.6]
JUNOS Kernel Software Suite [12.3R6.6]
JUNOS Crypto Software Suite [12.3R6.6]
JUNOS Online Documentation [12.3R6.6]
JUNOS Enterprise Software Suite [12.3R6.6]
JUNOS Packet Forwarding Engine Enterprise Software Suite [12.3R6.6]
JUNOS Routing Software Suite [12.3R6.6]
JUNOS Web Management [12.3R6.6]
JUNOS FIPS mode utilities [12.3R6.6]

username1@EX3200-J>

[download]

In reply to Screen Scraping from Juniper Switch using Expect.pm - Multiple Commands by julio-johnson

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