How to determine if OpenSSL and mod_ssl are installed on Apache2

If you have PHP installed on your server, you can create a php file, let's called it phpinfo.php and add this <?php echo phpinfo();?>, and open the file in your browser, this shows information about your system environment, to quickly find info about your Apache loaded modules, locate 'Loaded Modules' on the resulting page.

Usually, when you compile your apache2 server (or install it by packages facility stuff), you can check any directive that're available to be used by tapping this command:

~# $(which httpd) -L | grep SSL # on RHEL/CentOS/Fedora
~# $(which apache2) -L | grep SSL # on Ubuntu/Debian
~# $(which httpd2) -L | grep SSL # on SUSE

If you don't see any SSL* directive, it means that you don't have apache2 with mod_ssl compiled.

If you have PHP installed on your server, you can chek it in runtime using "extension_loaded" funciontion. Just like this:

<?php
if (!extension_loaded('openssl')) {
    // no openssl extension loaded.
}
?>