See https://github.com/uncyclomedia/mediawiki-config/blob/master/LocalSettings.php
Also, https://collaborate.mitre.org/gestalt/index.php/The_Why_And_How_of_Wiki_Farms is a complete walk-through (of one approach) to creating your farm.
See https://github.com/uncyclomedia/mediawiki-config/blob/master/LocalSettings.php
Also, https://collaborate.mitre.org/gestalt/index.php/The_Why_And_How_of_Wiki_Farms is a complete walk-through (of one approach) to creating your farm.