You can check which php.ini file is used on your system by creating a info.php file and storing it in your webroot folder. Simply create a file named info.php in your webroot (probably /var/www/html), paste the following code lines into the file and save.
<?php phpinfo(); ?>After that you can access the file and gain the information about your php-configuration via your browser under http://your-ip/info.php.
This will probably help to find out which php.ini file ihas to be updated.
regards
Gregor