Predefining Values for Customizable PHP Parameters

Plesk allows to define custom PHP configuration for a certain service
plan, add-on plan, subscription, website, and even subdomain. For this
purpose, the Plesk GUI exposes 16 most often used PHP parameters that
allow customization. The administrator or a customer can set the value
of each parameter either by selecting a value from a preset, typing a
custom value, or leaving the default value. In the latter case, Plesk
takes the parameter value from the server-wide PHP configuration.

Adding the following lines to the
panel.ini
file, you can specify what PHP parameters values will be available in
the preset and toggle the visibility of the custom value field.

Defining the Preset Values

To set the list of predefined values for a certain PHP parameter:

[php]
settings.<parameter_group>.<parameter_name>.values[]=<value>

where

• <parameter_group> - a group of a PHP parameter: performance
  for the performance PHP settings and general if the parameter is
  placed in to the common group. For more information about the groups
  of PHP parameters, read the Administrator’s
  Guide.
• <parameter_name> - a name of a PHP parameter. Use the same syntax
  as in php.ini.
• <value> - a parameter’s value added to the preset. Use the same
  syntax as in php.ini.

Add such line for each value in the preset. For example, if you want
Plesk users to choose the value of the memory_limit parameter
between 8M and 16M, add the following lines to
panel.ini:

[php]
settings.performance.memory_limit.values[]=8M
settings.performance.memory_limit.values[]=16M

Hiding the Custom Value Fields

To hide the field that allows entering the custom value for a certain
PHP parameter:

[php]
settings.<parameter_group>.<parameter_name>.custom=false

where

• <parameter_group> - a group of a PHP parameter: performance
  for the performance PHP settings and general if the parameter is
  placed in to the common group. For more information about the groups
  of PHP parameters, read the Administrator’s Guide,
• <parameter_name> - a name of a PHP parameter. Use the same syntax
  as in php.ini.

For example, if you do not want Plesk users to set custom values to the
memory_limit parameter, add the following line to
panel.ini:

[php]
settings.performance.memory_limit.custom=false

To switch the custom value field back on, replace false with
true.