TYPO3_CONF_VARS¶
The main configuration is achieved via a set of global settings
stored in a global array called $GLOBALS['TYPO3_CONF_VARS']
.
This chapter describes this global configuration in more details and gives hints to further configuration possibilities.
Note
This variable can be set in one of the following files:
File LocalConfiguration.php¶
The global configuration is stored in file typo3conf/LocalConfiguration.php
.
This file overrides default settings from typo3/sysext/core/Configuration/DefaultConfiguration.php
.
Important
Since configuration settings can be manipulated from within the
TYPO3 CMS backend, the typo3conf/LocalConfiguration.php
must be writable by the web server user.
The local configuration file is basically a long array which is simply returned
when the file is included. It represents the global TYPO3 configuration.
This configuration can be modified/extended/overridden by extensions,
by setting configuration options inside an extension's
ext_localconf.php
file. See extension files and locations
for more details about extension structure.
A typical content of typo3conf/LocalConfiguration.php
looks like this:
<?php
return [
'BE' => [
'debug' => true,
'explicitADmode' => 'explicitAllow',
'installToolPassword' => '$P$Cbp90UttdtIKELNrDGjy4tDxh3uu9D/',
'loginSecurityLevel' => 'normal',
],
'DB' => [
'Connections' => [
'Default' => [
'charset' => 'utf8',
'dbname' => 'empty_typo3',
'driver' => 'mysqli',
'host' => '127.0.0.1',
'password' => 'foo',
'port' => 3306,
'user' => 'bar',
],
],
],
'EXTCONF' => [
'lang' => [
'availableLanguages' => [
'de',
'eo',
],
],
],
'EXTENSIONS' => [
'backend' => [
'backendFavicon' => '',
'backendLogo' => '',
'loginBackgroundImage' => '',
'loginFootnote' => '',
'loginHighlightColor' => '',
'loginLogo' => '',
],
'extensionmanager' => [
'automaticInstallation' => '1',
'offlineMode' => '0',
],
'scheduler' => [
'maxLifetime' => '1440',
'showSampleTasks' => '1',
],
],
'FE' => [
'debug' => true,
'loginSecurityLevel' => 'normal',
],
'GFX' => [
'jpg_quality' => '80',
],
'MAIL' => [
'transport_sendmail_command' => '/usr/sbin/sendmail -t -i ',
],
'SYS' => [
'devIPmask' => '*',
'displayErrors' => 1,
'encryptionKey' => '0396e1b6b53bf48b0bfed9e97a62744158452dfb9b9909fe32d4b7a709816c9b4e94dcd69c011f989d322cb22309f2f2',
'exceptionalErrors' => 28674,
'sitename' => 'New TYPO3 site',
],
];
As you can see, the array is structured on two main levels. The first level corresponds roughly to a category, the second one being properties, which may themselves be arrays.
The configuration categories are:
- BE
- DB
- EXT
- EXTCONF
Backend-related language pack configuration resides here.
- EXTENSIONS
- FE
- GFX
- HTTP
Settings for tuning HTTP requests made by TYPO3.
- LOG
Options related to the sending of emails (transport, server, etc.).
- SVCONF
- SYS
General options which may affect both the frontend and the backend.
- T3_SERVICES
Service registration configuration and the backend.
Further details on the various configuration options can be found in the
Admin Tools module as well as the TYPO3 source at
EXT:core/Configuration/DefaultConfigurationDescription.yaml
.
The documentation shown in the Admin Tools module is automatically
extracted from those values of DefaultConfigurationDescription.yaml
.
The Admin Tools module provides various dedicated sections that
change parts of LocalConfiguration.php
, those can be found in
Admin Tools > Settings, most importantly section
Configure installation-wide options:

Configure installation-wide options Admin Tools > Settings¶

Configure installation-wide options with an active search¶
File AdditionalConfiguration.php¶
Although you can manually edit the typo3conf/LocalConfiguration.php
file, it is limited in scope because the file is expected to return
a PHP array. Also the file is rewritten every time an option is
changed in the Install Tool or some other operation (like changing
an extension configuration in the Extension Manager). Thus custom
code cannot reside in that file.
Such code should be placed in the typo3conf/AdditionalConfiguration.php
file. This file is never touched by TYPO3, so any code will be
left alone.
Furthermore this file is loaded after typo3conf/LocalConfiguration.php
,
which means it represents an opportunity to change global configuration
values programmatically if needed.
typo3conf/AdditionalConfiguration.php
is a plain PHP file.
There are no specific rules about what it may contain. However, since
the code is included on every request to TYPO3
- whether frontend or backend - you should avoid inserting code
which requires a lot of processing time.
Example: Changing the database hostname for development machines
<?php
$applicationContext = \TYPO3\CMS\Core\Core\Environment::getContext();
if ($applicationContext->isDevelopment()) {
$GLOBALS['TYPO3_CONF_VARS']['DB']['Connections']['Default']['host'] = 'mysql-be';
}
File DefaultConfiguration.php¶
TYPO3 comes with some default settings, which are defined in
file EXT:core/Configuration/DefaultConfiguration.php
.
This is the base configuration, the other files like LocalConfiguration.php
just overlay it.
Here is an extract of that file:
return [
'GFX' => [
'thumbnails' => true,
'thumbnails_png' => true,
'gif_compress' => true,
'imagefile_ext' => 'gif,jpg,jpeg,tif,tiff,bmp,pcx,tga,png,pdf,ai,svg',
// ...
],
// ...
];
It is certainly interesting to take a look into this file, which also contains values that are not displayed in the Install Tool and therefore cannot be changed easily.