According to requirements, we need to configure the php.ini into the best condition.

Step 1. Look for php.ini
1.1 init a PHP file and then write down this description

<?php
phpinfo();
?>

Step 2. revise upload_max_filesize = 100M

upload_max_filesize = 100M

Step3. Restart php server. Actually, we should restart apache2

/etc/init.d/apache2 restart