Upgrading from MediaWiki 1.18 to 1.33 and it's going badly.

[Syd Lexia]

Hello. My webhost recently upgraded my server's PHP from 5.4 to 7.2, and my wiki - which was running on 1.18 - stopped working. So, I attempted to upgrade from 1.18 to 1.33. This has not worked out thus far. I have enabled error logging: http://history.sydlexia.com/

Can anyone give me any advice on what to do?

I imagine my LocalSettings file is also a bit of mess, being as it's very old. Is there anywhere I can find a template of what a current LocalSettings file SHOULD look like?

[HSRobinson]

What you can do is rename your LocalSettings.php and then re-install MediaWiki into another database and then you will have a clean LocalSettings.php file.

[Skizzerz]

What error messages did you receive as part of the upgrade process?

Try generating a fresh LocalSettings.php as @HSRobinson suggested (installing to a new database, modifying the database name/password in LocalSettings.php to point to the existing 1.18 database, then running the updater again). If this method works, then the likely issue is that you forgot to update some skins or extensions -- when updating MediaWiki you also need to download the updates for all skins/extensions you use. If a skin or extension doesn't have updates between 1.18 and 1.33, it is likely not compatible with 1.33 and an alternative should be found.

[Syd Lexia]

These are the error messages I currently get:

[XmaIv1kALL6vyHmz7SgrrwAAAAc] / UnexpectedValueException from line 963 of /home/mrmiyagi/history.sydlexia.com/includes/libs/rdbms/loadbalancer/LoadBalancer.php: Got connection to 'sydwiki-syd_', but expected local domain ('sydwiki-mediawiki-syd_').

Backtrace:

#0 /home/mrmiyagi/history.sydlexia.com/includes/libs/rdbms/loadbalancer/LoadBalancer.php(892): Wikimedia\Rdbms\LoadBalancer->openLocalConnection(integer, integer)
#1 /home/mrmiyagi/history.sydlexia.com/includes/libs/rdbms/loadbalancer/LoadBalancer.php(755): Wikimedia\Rdbms\LoadBalancer->openConnection(integer, boolean, integer)
#2 /home/mrmiyagi/history.sydlexia.com/includes/objectcache/SqlBagOStuff.php(184): Wikimedia\Rdbms\LoadBalancer->getConnection(integer, array, boolean, integer)
#3 /home/mrmiyagi/history.sydlexia.com/includes/objectcache/SqlBagOStuff.php(278): SqlBagOStuff->getDB(integer)
#4 /home/mrmiyagi/history.sydlexia.com/includes/objectcache/SqlBagOStuff.php(240): SqlBagOStuff->fetchBlobMulti(array)
#5 /home/mrmiyagi/history.sydlexia.com/includes/libs/objectcache/BagOStuff.php(183): SqlBagOStuff->doGet(string, integer)
#6 /home/mrmiyagi/history.sydlexia.com/includes/libs/objectcache/CachedBagOStuff.php(57): BagOStuff->get(string, integer)
#7 /home/mrmiyagi/history.sydlexia.com/includes/session/SessionManager.php(917): CachedBagOStuff->get(string)
#8 /home/mrmiyagi/history.sydlexia.com/includes/session/SessionInfo.php(159): MediaWiki\Session\SessionManager->generateSessionId()
#9 /home/mrmiyagi/history.sydlexia.com/includes/session/SessionProvider.php(172): MediaWiki\Session\SessionInfo->__construct(integer, array)
#10 /home/mrmiyagi/history.sydlexia.com/includes/session/SessionManager.php(270): MediaWiki\Session\SessionProvider->newSessionInfo(NULL)
#11 /home/mrmiyagi/history.sydlexia.com/includes/session/SessionManager.php(244): MediaWiki\Session\SessionManager->getEmptySessionInternal(WebRequest)
#12 /home/mrmiyagi/history.sydlexia.com/includes/session/SessionManager.php(194): MediaWiki\Session\SessionManager->getEmptySession(WebRequest)
#13 /home/mrmiyagi/history.sydlexia.com/includes/WebRequest.php(748): MediaWiki\Session\SessionManager->getSessionForRequest(WebRequest)
#14 /home/mrmiyagi/history.sydlexia.com/includes/session/SessionManager.php(130): WebRequest->getSession()
#15 /home/mrmiyagi/history.sydlexia.com/includes/Setup.php(816): MediaWiki\Session\SessionManager::getGlobalSession()
#16 /home/mrmiyagi/history.sydlexia.com/includes/WebStart.php(77): require_once(string)
#17 /home/mrmiyagi/history.sydlexia.com/index.php(39): require(string)
#18 {main}

[Skizzerz]

If you see $wgDBmwschema in your LocalSettings.php, delete that line entirely.