Manual:LocalSettings.php

Overview
The file LocalSettings.php contains the local configuration of a MediaWiki installation. You should take your time to review the settings in this file. The file is usually generated by the web-based MediaWiki installer but you might want to tweak one or the other parameter (probably in concert with Apache settings).

Changing a settings usually means changing the value of a PHP variable. You might want to make yourself familiar with the PHP syntax first before going ahead. If you are too lazy, keep in mind that PHP variables are accessed by prepending a "$" character before the variable name.

Include Path
The IP (include path) variable holds the local file path to the base installation of your wiki. Make sure you refer to the fully qualified file path. Do not include a slash at the end of the path.

The DefaultSettings.php file gets loaded from the directory designated by the IP variable.

Site Name
The wgSitename variable holds the name of your wiki setup. This name gets included many times throughout the system. For instance, the Wikipedia tagline "'From Wikipedia, the free encyclopedia."' makes use of this setting.

Script Path
wgScriptPath is the URL path prefix to access the main MediaWiki script that is the central acting piece of code of MediaWiki. This setting should correspond to the Apache settings, especially if you are using Apache's rewrite rules.

Script Name
wgScript is the name of the main (index) MediaWiki PHP script, named index.php by default. You might want to tweak the path to the script while changing the script name is probably not a good idea. However, if you feel the urge to do so, this is the place to make your changes. Make sure you know what you are doing.

Redirect Script Name
The wgRedirectScript variable specifies the URL path to the redirect script which handles redirects in MediaWiki. This setting is similar to wgScript as you can configure the exact name of the script. As mentioned above, this is probably not a good idea unless you really know what you are doing.

Article Path
wgArticlePath is the path to use when accessing a page in MediaWiki. The path should contain the path to the main script (usually making use of wgScript) and use the $1 placeholder for the article name.

if you are using Apche rewrite rules to create pretty and short URLs, you probably need to adjust wgArticlePath to adress the right path. Note that wgArticlePath is used to construct URLs from with MediaWiki. If you make a mistake here, internal links will show up incorrectly while you still may be able to access the main page by specifying the correct URL manually.

Typical values are

Stylesheet Location
Use the wgStyleSheetPath variable to set the URL path to the place where the stylesheets (CSS) for the MediaWiki installation are located. The wgStyleSheetDirectory should point the same place, but note that this is a local file system path for use in internal scripts accessing the file system.

Upload Location
The upload directory is the place where files uploaded by the uses are stored. The wgUploadPath variable specifies the URL path, the wgUploadDirectory points to the local file system path.

Logo
The wgLogo variable specifies the relative URL pointing to the graphical logo that gets displayed on the top left corner by default. You might want to point the variable in the Upload Directory to be able to exchannge the logo by updating uploaded files.

Contact Info
The wgEmergencyContact variable is the e-mail address of the user to contact when shit happens. This e-mail address is used to send internal bug reports to. As an administrator, you want to include your e-mail address here.

The wgPasswordSender variable is the e-mail address where e-mail gets sent from, when passwords are sent out to users who have forgotten their passwords. Choose an address people can reply to in case of trouble or confusion.

Database Settings
MediaWiki needs access to the MySQL database to store pages, modifications, user information and a lot more things.

The wgDBserver contains the hostname where the database is hosted on. In most cases this will be just "localhost" as the database is run on the same system, but for distributed installations, you need to fill in the fully qualified domain name of the computer running the database.

wgDBname is the database name of the database to be used by MediaWiki. A single MySQL installation can store more than one database and you can even run many MediaWiki installations on a single server. Make sure you have stated the correct database name here and use different database names for different wiki installations on the the same database server.

The wgDBuser and wgDBpassword variables contain the login name and password to be used by MediaWiki to access the database. Make sure the specified user has the proper access rights to be able to manipulate the wiki's table on the database server.

Also keep in mind that the LocalSettings.php permissions should not allow other users to view this file as it contains security-related data.

Force Capital Links
By default, all article names are forced to start with a capital (roman) letter unless they start with a non-alphabetical character. If you want to to allow article names to start with a lowercase character you must adjust the wgCapitalLinks variable. Setting it to false allows lowercase characters, true chooses the default behaviour.

Direct SQL Queries
To allow SQL queries through the wiki's Special:Askaql page, you can enable direct SQL queries via the web interface. THIS IS VERY INSECURE. If you want to allow semipublic read-only SQL access for your sysops, you should define a MySQL user with limited privileges.

Review the MySQL documentation at http://www.mysql.com/doc/en/GRANT.html on how permissions can be granted in the database subsystem.

The wgAllowSysopQueries must be set to true if you want the direct SQL query feature to be turned on. The wgDBsqluser and the wgDBsqlpassword contain the login name and password to use to access the database with that feature.

Image Uploads
Before users are allowed to upload files to the MediaWiki system, you have to enable that feature. Make sure the Upload Directory is properly configured and writeable by the Apache web server process. Then set the wgDisableUploads to false to allow uploading in the web user interface.

If you want to be able to resize images on the fly to support thumbnails, MediaWiki needs a working ImageMagick installation. Set the variable $wgUseImageMagick to true once you have installed and tested ImageMagick on your system. Make sure the wgImageMagickConvertCommand variable points to the proper location of the convert command of your installation and that the command is executable by the web server process.

LaTeX inline equations
In order to render mathematical formulas in LaTeX, you need a working LaTeX installation on your system. Set the $wgUseTeX to true to enable that feature. Also make sure the wgMathPath, wgMathDirectory and wgTmpDirectory are set properly, but you might want to go with the default values unless you have a good reason to change it.

InterWiki support
InterWiki support is built into MediaWiki but you need to configure the prefix to be used for your internal links. This prefix is usually the same as wgSitename but in case you need to change that, you set the wgLocalInterwiki variable to the preferred name.

User Interface Language
MediaWiki allows for a variety of localized user interfaces languages instead of the english default. If you want to run your wiki in a non-english language, set the wgLanguageCode variable to the proper language code (e.g. "de" for german, "es" for spanish etc.)