use warnings;
use strict;
use XML::Twig;
my $twig = XML::Twig->new( twig_handlers => { httpsRoute => \&httpsRou
+te } );
$twig->parsefile('test.xml');

sub httpsRoute {
    my ( $twig, $httpsRoute ) = @_;
    print $httpsRoute->att('hostname'), "\n";
    print $httpsRoute->att('tier'), "\n";
    print $httpsRoute->first_child('key')->text(), "\n";
    print "\n";
}

__END__

hostname1.xxx.com
dmz
6924

hostname3.xxx.com
dmz
9990068
[download]

Use open to print to a file.