I am trying to install froxlor on Ubuntu 14.04 and have already installed the PHP5 MYSQL PDO Extension.
When running code:
php -i|grep PDO
PDO support => enabled
PDO drivers => mysql
PDO Driver for MySQL => enabled
There are at least three different php.ini files when using php on Ubuntu.
/etc/php5/cli/php.ini /etc/php5/apache2/php.ini /etc/php5/cgi/php.ini
They can differ and depending on how php is invoked one or the other .ini file is used.
phpinfo() / php -i can tell you which one was used.