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(Cannot access the database)
Backtrace:
#0 /var/lib/mediawiki/includes/libs/rdbms/loadbalancer/LoadBalancer.php(972): Wikimedia\Rdbms\LoadBalancer->reportConnectionError() #1 /var/lib/mediawiki/includes/libs/rdbms/loadbalancer/LoadBalancer.php(944): Wikimedia\Rdbms\LoadBalancer->getServerConnection() #2 /var/lib/mediawiki/includes/libs/rdbms/database/DBConnRef.php(95): Wikimedia\Rdbms\LoadBalancer->getConnectionInternal() #3 /var/lib/mediawiki/includes/libs/rdbms/database/DBConnRef.php(101): Wikimedia\Rdbms\DBConnRef->ensureConnection() #4 /var/lib/mediawiki/includes/libs/rdbms/database/DBConnRef.php(313): Wikimedia\Rdbms\DBConnRef->__call() #5 /var/lib/mediawiki/includes/language/LCStoreDB.php(66): Wikimedia\Rdbms\DBConnRef->selectField() #6 /var/lib/mediawiki/includes/language/LocalisationCache.php(451): LCStoreDB->get() #7 /var/lib/mediawiki/includes/language/LocalisationCache.php(497): LocalisationCache->isExpired() #8 /var/lib/mediawiki/includes/language/LocalisationCache.php(373): LocalisationCache->initLanguage() #9 /var/lib/mediawiki/includes/language/LocalisationCache.php(314): LocalisationCache->loadItem() #10 /var/lib/mediawiki/includes/language/Language.php(3134): LocalisationCache->getItem() #11 /var/lib/mediawiki/includes/specialpage/SpecialPageFactory.php(1179): Language->getSpecialPageAliases() #12 /var/lib/mediawiki/includes/specialpage/SpecialPageFactory.php(1238): MediaWiki\SpecialPage\SpecialPageFactory->getAliasList() #13 /var/lib/mediawiki/includes/Title.php(1287): MediaWiki\SpecialPage\SpecialPageFactory->resolveAlias() #14 /var/lib/mediawiki/includes/MediaWiki.php(212): Title->isSpecial() #15 /var/lib/mediawiki/includes/MediaWiki.php(904): MediaWiki->performRequest() #16 /var/lib/mediawiki/includes/MediaWiki.php(562): MediaWiki->main() #17 /var/lib/mediawiki/index.php(50): MediaWiki->run() #18 /var/lib/mediawiki/index.php(46): wfIndexMain() #19 {main}