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(Cannot access the database)
Backtrace:
#0 /var/www/mediawiki/includes/libs/rdbms/loadbalancer/LoadBalancer.php(873): Wikimedia\Rdbms\LoadBalancer->reportConnectionError() #1 /var/www/mediawiki/includes/libs/rdbms/loadbalancer/LoadBalancer.php(861): Wikimedia\Rdbms\LoadBalancer->getServerConnection() #2 /var/www/mediawiki/includes/libs/rdbms/database/DBConnRef.php(99): Wikimedia\Rdbms\LoadBalancer->getConnectionInternal() #3 /var/www/mediawiki/includes/libs/rdbms/database/DBConnRef.php(117): Wikimedia\Rdbms\DBConnRef->ensureConnection() #4 /var/www/mediawiki/includes/libs/rdbms/database/DBConnRef.php(722): Wikimedia\Rdbms\DBConnRef->__call() #5 /var/www/mediawiki/includes/libs/rdbms/database/Database.php(2964): Wikimedia\Rdbms\DBConnRef->getSessionLagStatus() #6 /var/www/mediawiki/includes/cache/LinkCache.php(460): Wikimedia\Rdbms\Database::getCacheSetOptions() #7 /var/www/mediawiki/includes/libs/objectcache/wancache/WANObjectCache.php(1758): LinkCache->{closure}() #8 /var/www/mediawiki/includes/libs/objectcache/wancache/WANObjectCache.php(1589): WANObjectCache->fetchOrRegenerate() #9 /var/www/mediawiki/includes/cache/LinkCache.php(455): WANObjectCache->getWithSetCallback() #10 /var/www/mediawiki/includes/cache/LinkCache.php(504): LinkCache->getGoodLinkRowInternal() #11 /var/www/mediawiki/includes/page/PageStore.php(187): LinkCache->getGoodLinkRow() #12 /var/www/mediawiki/includes/page/PageStore.php(154): MediaWiki\Page\PageStore->getPageByNameViaLinkCache() #13 /var/www/mediawiki/includes/page/PageStore.php(326): MediaWiki\Page\PageStore->getPageByName() #14 /var/www/mediawiki/includes/title/Title.php(4164): MediaWiki\Page\PageStore->getPageByReference() #15 /var/www/mediawiki/includes/title/Title.php(2898): MediaWiki\Title\Title->getFieldFromPageStore() #16 /var/www/mediawiki/includes/OutputPage.php(1235): MediaWiki\Title\Title->isRedirect() #17 /var/www/mediawiki/includes/OutputPage.php(1255): OutputPage::buildBacklinkSubtitle() #18 /var/www/mediawiki/includes/specials/SpecialWhatLinksHere.php(138): OutputPage->addBacklinkSubtitle() #19 /var/www/mediawiki/includes/specialpage/FormSpecialPage.php(229): SpecialWhatLinksHere->onSuccess() #20 /var/www/mediawiki/includes/specialpage/SpecialPage.php(701): FormSpecialPage->execute() #21 /var/www/mediawiki/includes/specialpage/SpecialPageFactory.php(1475): SpecialPage->run() #22 /var/www/mediawiki/includes/MediaWiki.php(327): MediaWiki\SpecialPage\SpecialPageFactory->executePath() #23 /var/www/mediawiki/includes/MediaWiki.php(923): MediaWiki->performRequest() #24 /var/www/mediawiki/includes/MediaWiki.php(576): MediaWiki->main() #25 /var/www/mediawiki/index.php(50): MediaWiki->run() #26 /var/www/mediawiki/index.php(46): wfIndexMain() #27 {main}