At a glance, it looks like you need to replace &lt; with < and &gt; with > to make it work. Ie. 

use strict;
use warnings;
use autodie;

$template_file_name="configtemplate.txt";
while(<>) {

   ($location, $hostname, $ip) 
       = split (/,/);

   open(TFILE, "< $template_file_name") || die "config template file $
+template_file_name: $!\n";
   $ofile_name = $name . ".txt";
   open(OFILE, "> $ofile_name") || die "output config file $ofile_name
+: $!\n";

   while (<TFILE>) {

     s/##location##/$location/;
     s/##hostname##/$name/;
     s/##ip##/$ip/;


     printf OFILE $_;
   }
}

[download]

Some comments:

The line $ofile_name = $name . ".txt"; uses a variable $name which is not defined. Should this be $hostname probably?

In your file with the CSV variables change the first line to # ip,hostname,location and add a line to filter out comment lines starting with # like this:

while(<>) {
  next if /^#/;
...

[download]

I have not run the code as the template file is not present, so there might be glitches in my code.

In reply to Re: How do I use a template, csv file and script to generate multiple switch configurations by hdb
in thread How do I use a template, csv file and script to generate multiple switch configurations by hvh2000

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