I was having the same problem myself with a project I'm working on. The following excerpt from the Net::SSH::Perl documentation may be pertinent...

"..if you're running in an interactive session and you've not provided a password, you'll be prompted for one..."

But what is interactive mode? It appears to be through the use of Net::SSH::Perl->shell(), which "Opens up an interactive shell on the remote machine and connects it to your STDIN. This is most effective when used with a pseudo tty; otherwise you won't get a command line prompt, and it won't look much like a shell. For this reason--unless you've specifically declined one--a pty will be requested from the remote machine, even if you haven't set the use_pty argument to new..."

It sounds like the only way to connect interactively is to use shell() or grab the password, handing it off to login() beforehand. Hope this helps.

-fuzzyping

UPDATE:

The problem is not what I described above... you're simply missing the interactive option with login. Your code should look something like...
#!/usr/local/bin/perl -w

use strict;
use Net::SSH::Perl;
use Data::Dumper;

my $ssh = Net::SSH::Perl->new( "localhost", debug => 1, protocol => 2,
+ interactive => 1, use_pty => 1 );

$ssh->login();

my ($out, $err, $exit ) = $ssh->cmd('su - root -c "touch /var/tmp/sill
+y3"', '*******');
print "out = $out\nerr = $err\nexit = $exit\n";

[download]

FWIW, I'm still getting STDIN/tty errors to $err, but it is running interactively and asking for my password. It appears to be a limitation of su, requiring local tty control(?). There are others here who would be better qualified to answer that one. I have no problem running non-su commands, though. Good Luck!

-fuzzyping

In reply to Re: Net::SSH::Perl and su by fuzzyping
in thread Net::SSH::Perl and su by mikfire

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.