In case its helpful to anyone, I recently needed to test GlobalUsage on my local test install, which needed this var set up.
Here's what I used to set up a no-frill "wikifarm" of 3 mediawiki installs. All in different db's (although if using db prefixes, wouldn't be too different, I think you just use a dash in the db name), all the db's in the same server, and only master db's (no slaves). I mostly just edited things until it worked, so not 100% sure if proper way. Anyways, perhaps this would be helpful to someone:
// This is in LocalSettings.php for all 3 wikis. // $wgDBname must be set earlier as appropriate. ($wgDBname = 'wikidb1';) $wgDBuser = 'your db username'; //must be same for all 3 wikis in this simplified setup $wgDBpassword = 'pass'; // Same pass must be usable for all 3 wikis $wgLBFactoryConf = array( 'class' => 'LBFactory_Multi', 'sectionsByDB' => array( 'wikidb1' => 's1', // Assumes db name for first wiki is wikidb1 'wikidb2' => 's1', // and so on. 'wikidb3' => 's1', ), 'sectionLoads' => array( 's1' => array( 'localhost' => 0, // All on section s1, which has single master, at localhost. ), ), 'serverTemplate' => array( 'dbname' => $wgDBname, 'user' => $wgDBuser, 'password' => $wgDBpassword, 'type' => 'mysql', 'flags' => DBO_DEFAULT, 'max lag' => 30, ), );
Bawolff 10:20, 3 January 2012 (UTC)