Rápido e caceteiro.
Crie o arquivo /etc/httpd/conf.d/default.conf com o conteúdo abaixo:
<VirtualHost _default_:80>
RewriteEngine On
RewriteCond %{HTTPS} !=on
RewriteCond %{HTTP_HOST} !^(localhost|127.0.0.1)
RewriteRule ^/(.*) https://%{SERVER_NAME}/$1 [R=301,L]
</VirtualHost>
RewriteEngine On
RewriteCond %{HTTPS} !=on
RewriteCond %{HTTP_HOST} !^(localhost|127.0.0.1)
RewriteRule ^/(.*) https://%{SERVER_NAME}/$1 [R=301,L]
</VirtualHost>