This wiki page explains how to modify php.ini file or .htaccess file to support large-size uploads in PHP applications. Such issues usually happens when you try to record 2-3 minutes of audio/video streams and resulting Blobs size gets bigger/larger than 10MB.

References:

1. https://github.com/muaz-khan/WebRTC-Experiment/issues/224#issuecomment-46087136
2. https://github.com/muaz-khan/WebRTC-Experiment/issues/281

It is a common case among all PHP default installations. You should define following values in .htaccess file if you've root-level privileges.

<IfModule mod_php4.c>
php_value session.gc_maxlifetime 10800
php_value max_input_time 10800
php_value max_execution_time 10800
php_value upload_max_filesize 500M
php_value post_max_size 500M
</IfModule>

Above technique rarely works on Amazon EC2. You need to login as root-user to the terminal; then search for all php.ini files:

find /etc/ -name "php.ini"

There should be php.ini file located in your appache installation directory. Its location varies for each installation that's why you should check all php.ini files.

vim php.ini

// or otherwise you can use "vi"
vi php.ini

Above command will open editing mode; then you should search and edit following values:

/session.gc_maxlifetime
/max_input_time
/max_execution_time
/upload_max_filesize
/post_max_size

Each line is searching a specific string. Note: Above command may work in replace mode instead of insert mode.

You should change default values to:

session.gc_maxlifetime=10800
max_input_time=10800
max_execution_time=10800
upload_max_filesize=500M
post_max_size=500M

Remember, NEVER forget "max_execution_time" because usually ffmpeg execution process takes time to transcode and merge webm.

:wq command can be used to save changes and close editing mode. You need to type this command in "replace" mode.

Note: You can navigate between insert and replace modes by simply pressing insert key.

You MUST restart/reboot appache server to make sure new changes are applied.

Please don't forget to set a temporary PHP page where you can check PHP-info:

<?php

// Show all information, defaults to INFO_ALL
phpinfo();

?>

Now, open that PHP page and search for all above values e.g. post_max_size etc.

[sudo] chmod 755 ./uploads
[sudo] chown -R www-data:www-data ./uploads
[sudo] chown -R apache:apache ./uploads
[sudo] chmod -R a+rwX ./*

P.S. Sometimes you need to manually set read/write access for directories like "uploads" however your demo has privileges to read/write WAV/WebM files in uploads directory.