Perl Script to enable Cisco

Null_Route0 has asked for the wisdom of the Perl Monks concerning the following question:

Hi all - Just getting my feet wet for the first time with some Perl scripting and I had two questions. I am working on a script to log into a Cisco and do a "show run" and dump the output to a text file. Im using the Net::SSH::Perl module which doesnt appear to support the enable command. Im not sure how I can get it into enable mode. Also need some advice on the creation of the txt file. I have the script create a file based on the host name, but it always seems to plop a ? at the end of the txt file and Im not sure why. Any advice would be much appreciated.

#!/usr/bin/perl -w

use strict;
use warnings;
use 5.010;

###prompt for host###
print "Host IP ";
my $host = <>;

##Setup connection###
use Net::SSH::Perl;
my $ssh = Net::SSH::Perl->new($host);
$ssh->login('user', 'pw');

###run commands###
my($run) = $ssh->cmd("show run");

##create file and write to it###
my $filename = $host;
open(my $fh, '>', $filename) or die "Could not open file '$filename' $
+!";
say $fh ($run);
close $fh;
say 'done'
[download]

Comment on Perl Script to enable Cisco Download Code

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Re: Perl Script to enable Cisco by aitap (Curate) on Jul 23, 2012 at 16:04 UTC
What do you mean by "enable command"? Shell commands are supported by remote hosts, not Perl modules. As for the text file, you may want to use `print` instead of `say`. The "?" character `say` adds is actually a newline symbol, `\n`. Under Windows newline symbol is different (`\r\n`), so you may `print` that instead. Sorry if my advice was wrong.	[reply] [d/l] [select]
Re^2: Perl Script to enable Cisco by Null_Route0 (Initiate) on Jul 23, 2012 at 17:12 UTC
Thanks for the clarification with /n What I mean by enable command is this... On a Cisco there is a whole subset of commands you can run from privileged mode. To do that you type the command "enable" and then are prompted for a password. Im just not sure how I go about scripting that out. I tried like this, but it didnt work `###run commands### $ssh->cmd("enable theEnablePassword");` [download] Tried like this too `$ssh->cmd("enable"); $ssh->cmd("theEnablePassword");` [download] Not sure if I explained that right.	[reply] [d/l] [select]
Re^3: Perl Script to enable Cisco by dasgar (Priest) on Jul 23, 2012 at 18:13 UTC
Since it sounds like you'll need to your script to interactively respond to the remote device, I think that you need to use something like Expect. I personally have never used expect, so I can't offer up more details on how to use expect. Based on my limited knowledge of expect, I believe that it can be used to issue a command, what for a specific response, and then issue another command based on the response received.	[reply]
Re^4: Perl Script to enable Cisco by Null_Route0 (Initiate) on Jul 23, 2012 at 18:17 UTC
Re^3: Perl Script to enable Cisco by aitap (Curate) on Jul 23, 2012 at 17:33 UTC
What do these commands return? I mean, what if you try to `say $ssh->cmd("enable theEnablePassword");`? Sorry if my advice was wrong.	[reply] [d/l]
Re^4: Perl Script to enable Cisco by Null_Route0 (Initiate) on Jul 23, 2012 at 18:05 UTC
Re^5: Perl Script to enable Cisco by aitap (Curate) on Jul 23, 2012 at 18:12 UTC
Re: Perl Script to enable Cisco by i5513 (Pilgrim) on Jul 23, 2012 at 18:30 UTC
Of course, it is ok playing with ssh / telnet / expect modules, but sometimes there are programs which work like you expect. Not need of reinvent the weel :-) For this case (and if you are not in Windows OS), I recommend you take a look to rancid, and its ~ "/.login/" commands	[reply]
Re^2: Perl Script to enable Cisco by Null_Route0 (Initiate) on Jul 23, 2012 at 18:40 UTC
Running Fedora 16 so I'll take a look at Rancid. I figured this project would be a fun introduction to the wild world of Perl =) Its much easier to learn things when you have some sort of context to work with and I've learned a ton, but I just wish I had a little more success getting this to work	[reply]