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(Cannot access the database)
Backtrace:
#0 /var/www/html/includes/libs/rdbms/loadbalancer/LoadBalancer.php(897): Database->reportConnectionError('Connection refu...')
#1 /var/www/html/includes/libs/rdbms/loadbalancer/LoadBalancer.php(572): LoadBalancer->reportConnectionError()
#2 /var/www/html/includes/GlobalFunctions.php(3075): LoadBalancer->getConnection(0, Array, false)
#3 /var/www/html/includes/cache/MessageCache.php(444): wfGetDB(-1)
#4 /var/www/html/includes/cache/MessageCache.php(403): MessageCache->loadFromDB('ru', NULL)
#5 /var/www/html/includes/cache/MessageCache.php(325): MessageCache->loadFromDBWithLock('ru', Array, NULL)
#6 /var/www/html/includes/cache/MessageCache.php(927): MessageCache->load('ru')
#7 /var/www/html/includes/cache/MessageCache.php(857): MessageCache->getMsgFromNamespace('Gadgets-definit...', 'ru')
#8 /var/www/html/includes/cache/MessageCache.php(826): MessageCache->getMessageForLang(Object(LanguageRu), 'gadgets-definit...', true, Array)
#9 /var/www/html/includes/cache/MessageCache.php(766): MessageCache->getMessageFromFallbackChain(Object(LanguageRu), 'gadgets-definit...', true)
#10 /var/www/html/includes/Message.php(1188): MessageCache->get('gadgets-definit...', true, Object(LanguageRu))
#11 /var/www/html/includes/Message.php(950): Message->fetchMessage()
#12 /var/www/html/extensions/Gadgets/includes/MediaWikiGadgetsDefinitionRepo.php(113): Message->exists()
#13 /var/www/html/extensions/Gadgets/includes/MediaWikiGadgetsDefinitionRepo.php(83): MediaWikiGadgetsDefinitionRepo->fetchStructuredList()
#14 /var/www/html/includes/libs/objectcache/WANObjectCache.php(1004): MediaWikiGadgetsDefinitionRepo->{closure}(false, 86400, Array, NULL)
#15 /var/www/html/includes/libs/objectcache/WANObjectCache.php(906): WANObjectCache->doGetWithSetCallback('wikidb-hzg_:gad...', 86400, Object(Closure), Array)
#16 /var/www/html/extensions/Gadgets/includes/MediaWikiGadgetsDefinitionRepo.php(90): WANObjectCache->getWithSetCallback('wikidb-hzg_:gad...', 86400, Object(Closure), Array)
#17 /var/www/html/extensions/Gadgets/includes/MediaWikiGadgetsDefinitionRepo.php(23): MediaWikiGadgetsDefinitionRepo->loadGadgets()
#18 /var/www/html/extensions/Gadgets/includes/GadgetRepo.php(36): MediaWikiGadgetsDefinitionRepo->getGadgetIds()
#19 /var/www/html/extensions/Gadgets/GadgetHooks.php(52): GadgetRepo->getStructuredList()
#20 /var/www/html/includes/Hooks.php(195): GadgetHooks::userGetDefaultOptions(Array)
#21 /var/www/html/includes/user/User.php(1552): Hooks::run('UserGetDefaultO...', Array)
#22 /var/www/html/includes/user/User.php(5131): User::getDefaultOptions()
#23 /var/www/html/includes/user/User.php(2768): User->loadOptions()
#24 /var/www/html/includes/context/RequestContext.php(364): User->getOption('language')
#25 /var/www/html/includes/cache/HTMLFileCache.php(136): RequestContext->getLanguage()
#26 /var/www/html/includes/MediaWiki.php(528): HTMLFileCache::useFileCache(Object(RequestContext), 1)
#27 /var/www/html/index.php(43): MediaWiki->run()
#28 {main}