How to change the limit of uploaded file size in php?

Edit the following configurations in the php.ini file, and then restart webserver (apache).

upload_max_filesize = 10M
post_max_size = 20M

You may find the php.ini file in /etc/php5/apache2 directory of ubuntu. If you forget the location of ini file, you may find it by running a simple php file as below.

<?php
   phpinfo();
?>

Note: you will probably require write permission to edit the php.ini file.

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