#!/usr/bin/perl -w
use Net::SSH::Perl

my  $ssh = Net::SSH::Perl->new("$_");
    $ssh->login("user1", "pass1");
    
open (IN,  "<hosts.txt" ) || die "Can't open users.txt";

 while(<IN>) {
  chomp;

    $ssh->cmd("passwd");
    $ssh->cmd("whatever");   
    $ssh->cmd("whatever");

}