#!/usr/bin/perl

use strict;
use warnings;
use DBI;
use DBD::Oracle qw(:ora_session_modes);

my $dbhost = "my.server.name";
my $dbuser = "sys"; # not "system" or "/"
my $dbpass = "password";

my $sid = "SIDNAME";

my $dbh = DBI->connect(
  "dbi:Oracle:host=$dbhost;sid=$sid", 
  $dbuser, 
  $dbpass, 
  { ora_session_mode => ORA_SYSDBA }
);

if ($dbh) {
  print "Connected\n";
} else {
  die $DBI::errstr;
}

$dbh->disconnect;