Why, when collecting configs from switches, does it (config) fall down all into one long line?

Question

Perl

I'm testing a script that bypasses the switches and merges the current config from them:

#!/usr/bin/perl
use Net::Telnet;
use DBI;
my $ip;
my $name = 'adm';
my $pass = '12345678';
my $qry = ("SELECT ip FROM computers WHERE unit_id='76' ORDER BY ip");
my $dbh = DBI -> connect ("DBI:Pg:dbname=info user=info_bckp_switch host=10.0.0.4 password=qwerty");
my $sth = $dbh -> prepare($qry);
my $rv = $sth -> execute();
if (!defined $rv) {
  print "ERROR on while execute '$qry': " . $dbh->errstr . "\n";
  exit(0);
}
###################################################################################################
while (my @row = $sth -> fetchrow_array())
{    
    $ip = $row[0]; #get ip switch
    foreach $ip(@row)
    {
        my $ping =  "ping -c 1 -q $ip";
         my @lines = `$ping`;
            for my $line (@lines)
        {
         if ($line =~ /\s+(\d+)% packet loss/)
          {
                 if ($1 eq '100')
                 {
            print "$ip - FAIL!\n"
            }
            else
            {
            print "$ip - OK!, then backup config $ip to continue...\n";
             &getconf();
            }
        }
        }
    }   
}    
#########################################################################################################
sub getconf {
    $file_name = $number = substr($ip,7,10); #strip ip address
    $file_name =~ s/$number/switch$number.cfg/; #rename config file
        system "unlink /var/tftp/$file_name";
        system "touch      /var/tftp/$file_name";
        system "chmod 0666 /var/tftp/$file_name";
    $telnet = new Net::Telnet (Timeout=>50,Prompt=>'/#/'); #make object net
    $telnet -> open($ip); #connect to switch
    $telnet -> login($name, $pass); #enter to switch
    $telnet -> cmd('dis cli'); #for full output
         $cmd1="show switch";
         $cmd2="upload cfg_toTFTP 10.0.107.45 $file_name";
         $cmd3="upload cfg_toTFTP 10.0.107.45 dest_file $file_name"; #for HardVer C1
            
    @lines = $telnet -> cmd($cmd1);
    chomp (@lines);
    foreach $line (@lines)
    {    
         ($val) = $line =~ /Hardware Version\s+:\s+([A-Z0-9]+)/;
         next unless $val;
    
        if ($val eq "C1")
        {
        $telnet -> cmd($cmd3);
        }
        else
        {
        $telnet -> cmd($cmd2);
         }
    }
    $telnet -> print('$cmd');
    $telnet -> waitfor('/#/');
    $telnet -> print ('logout');
    $telnet -> close;
    open(IF, "< /var/tftp/$file_name") or die $!;
    open(OF, "> /var/tftp/$file_name.tmp") or die $!;
    while(<IF>)
    {
        chomp;
        s/create account admin sa//g;
        s/11388019//g;
        print OF $_;
    }
    close (OF);
    close (IF);
        rename "/var/tftp/$file_name", "/var/tftp/$file_name.bkp";
        rename "/var/tftp/$file_name.tmp", "/var/tftp/$file_name";
        unlink "/var/tftp/$file_name.bkp";
        $date = `date +%d-%m-%Y--%H-%M`;
        open(IF, ">> /var/tftp/$file_name") or die $!;
        print IF "\n#$date";
        close (IF);
        system "chmod 0666 /var/tftp/$file_name";
}
$sth -> finish();
$dbh -> disconnect();

But as a result, the config falls down all into one long line,
and about 170 connections are found in the switch logs by this script, instead of one.
Please help me find the bugs!
Any comments and suggestions for improvement are welcome!

Answer 1

I correctly determined during a cursory review that you process line by line all the received configs like this:

{
        chomp;
        s/create account admin sa//g;
        s/11388019//g;
        print OF $_;
    }

As a result, the entire file is obtained in one line.
chomp, bites off the newline from $_, but the print does not add it, so the whole config is obtained in one line.
Fix the print.