MediaWiki:Config-json/en

Fatal: PHP was compiled without JSON support. You must install either the PHP JSON extension or the PECL jsonc extension before installing MediaWiki.
 * The PHP extension is included in Red Hat Enterprise Linux (CentOS) 5 and 6, though must be enabled in  or.
 * Some Linux distributions released after May 2013 omit the PHP extension, instead packaging the PECL extension as  or.