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(Cannot access the database)
Backtrace:
#0 /usr/share/mediawiki/includes/libs/rdbms/loadbalancer/LoadBalancer.php(972): Wikimedia\Rdbms\LoadBalancer->reportConnectionError() #1 /usr/share/mediawiki/includes/libs/rdbms/loadbalancer/LoadBalancer.php(944): Wikimedia\Rdbms\LoadBalancer->getServerConnection() #2 /usr/share/mediawiki/includes/libs/rdbms/database/DBConnRef.php(95): Wikimedia\Rdbms\LoadBalancer->getConnectionInternal() #3 /usr/share/mediawiki/includes/libs/rdbms/database/DBConnRef.php(101): Wikimedia\Rdbms\DBConnRef->ensureConnection() #4 /usr/share/mediawiki/includes/libs/rdbms/database/DBConnRef.php(313): Wikimedia\Rdbms\DBConnRef->__call() #5 /usr/share/mediawiki/includes/language/LCStoreDB.php(61): Wikimedia\Rdbms\DBConnRef->selectField() #6 /usr/share/mediawiki/includes/language/LocalisationCache.php(451): LCStoreDB->get() #7 /usr/share/mediawiki/includes/language/LocalisationCache.php(497): LocalisationCache->isExpired() #8 /usr/share/mediawiki/includes/language/LocalisationCache.php(373): LocalisationCache->initLanguage() #9 /usr/share/mediawiki/includes/language/LocalisationCache.php(314): LocalisationCache->loadItem() #10 /usr/share/mediawiki/includes/language/Language.php(492): LocalisationCache->getItem() #11 /usr/share/mediawiki/includes/language/Language.php(713): Language->getNamespaces() #12 /usr/share/mediawiki/includes/language/Language.php(736): Language->getNamespaceIds() #13 /usr/share/mediawiki/includes/title/MediaWikiTitleCodec.php(415): Language->getNsIndex() #14 /usr/share/mediawiki/includes/Title.php(2982): MediaWikiTitleCodec->splitTitleString() #15 /usr/share/mediawiki/includes/Title.php(480): Title->secureAndSplit() #16 /usr/share/mediawiki/includes/MediaWiki.php(89): Title::newFromURL() #17 /usr/share/mediawiki/includes/MediaWiki.php(162): MediaWiki->parseTitle() #18 /usr/share/mediawiki/includes/MediaWiki.php(860): MediaWiki->getTitle() #19 /usr/share/mediawiki/includes/MediaWiki.php(562): MediaWiki->main() #20 /usr/share/mediawiki/index.php(50): MediaWiki->run() #21 /usr/share/mediawiki/index.php(46): wfIndexMain() #22 {main}