To important folders where you will be updating certain files are:
- \var\lib\mediawiki
- \etc\mediawiki
Including many other useful scripts, to export and import XML dump, there are scripts (dumpBackup.php, importDump.php) available in the (\var\lib\mediawiki\maintenance) folder.
To export my own mediawiki, I used following command, which creates dump.xml file in temp folder that contains only current pages of the wiki. To backup everything, you can use --full instead. More detail instruction are available here.
php dumpBackup.php --current >/tmp/dump.xml
