When deploying PHP applications on AWS Elastic Beanstalk, you might need to modify PHP configuration settings like upload_max_filesize or post_max_size. However, these settings can't be changed through the standard .ebextensions option_settings because the aws:elasticbeanstalk:container:php:phpini namespace doesn't support extension.

The most reliable method is to create a custom php.ini file and deploy it during the instance setup phase. Here's how:

files:
  "/etc/php.d/my_settings.ini":
    mode: "000644"
    owner: root
    group: root
    content: |
      upload_max_filesize = 64M
      post_max_size = 64M
      memory_limit = 128M
      max_execution_time = 300

For some PHP settings, you can use .htaccess in your application root:

php_value upload_max_filesize 64M
php_value post_max_size 64M
php_value memory_limit 128M

After deployment, create a PHP info file to verify your settings:

<?php
phpinfo();
?>

For different PHP versions, you might need to place the ini file in different locations:

commands:
  create_php_ini:
    command: |
      if [ -d "/etc/php/7.4/apache2/conf.d" ]; then
        echo "upload_max_filesize = 64M" > /etc/php/7.4/apache2/conf.d/my_settings.ini
      elif [ -d "/etc/php5/apache2/conf.d" ]; then
        echo "upload_max_filesize = 64M" > /etc/php5/apache2/conf.d/my_settings.ini
      fi

• Always test configuration changes in a staging environment first
• Remember that some PHP settings can only be changed in php.ini
• After modifying php.ini, you'll need to restart your web server

When deploying PHP applications on AWS Elastic Beanstalk, you'll encounter scenarios where standard PHP configuration options like upload_max_filesize and post_max_size can't be modified through the usual .ebextensions mechanism. This occurs because these directives belong to the non-extensible aws:elasticbeanstalk:container:php:phpini namespace.

The most reliable method involves creating a custom .user.ini file that Elastic Beanstalk will merge with the main PHP configuration:

files:
  "/etc/php.d/custom.ini":
    mode: "000644"
    owner: root
    group: root
    content: |
      upload_max_filesize = 64M
      post_max_size = 64M
      max_execution_time = 300
      memory_limit = 128M

For applications using Apache, you can also configure these settings in your document root's .htaccess file:

php_value upload_max_filesize 64M
php_value post_max_size 64M
php_value max_execution_time 300

To confirm your changes took effect, create a simple PHP info script:

<?php
phpinfo();
?>

Deploy this file temporarily and check that your custom values appear in the PHP configuration section.

• Changes require an environment rebuild for .user.ini modifications
• Always test changes in a staging environment first
• Consider EC2 instance type when increasing memory limits
• Monitor ELB timeout settings which may also affect large uploads