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(Cannot access the database)
Backtrace:
#0 /var/www/public_html/ru/includes/libs/rdbms/loadbalancer/LoadBalancer.php(897): Database->reportConnectionError('Unknown error (...')
#1 /var/www/public_html/ru/includes/libs/rdbms/loadbalancer/LoadBalancer.php(572): LoadBalancer->reportConnectionError()
#2 /var/www/public_html/ru/includes/GlobalFunctions.php(3075): LoadBalancer->getConnection(-1, 'recentchanges', false)
#3 /var/www/public_html/ru/includes/specials/SpecialRecentchanges.php(287): wfGetDB(-1, 'recentchanges')
#4 /var/www/public_html/ru/includes/specials/SpecialRecentchanges.php(534): SpecialRecentChanges->getDB()
#5 /var/www/public_html/ru/includes/specials/SpecialRecentchanges.php(57): SpecialRecentChanges->checkLastModified()
#6 /var/www/public_html/ru/includes/specialpage/SpecialPage.php(522): SpecialRecentChanges->execute(NULL)
#7 /var/www/public_html/ru/includes/specialpage/SpecialPageFactory.php(576): SpecialPage->run(NULL)
#8 /var/www/public_html/ru/includes/MediaWiki.php(283): SpecialPageFactory::executePath(Object(Title), Object(RequestContext))
#9 /var/www/public_html/ru/includes/MediaWiki.php(851): MediaWiki->performRequest()
#10 /var/www/public_html/ru/includes/MediaWiki.php(512): MediaWiki->main()
#11 /var/www/public_html/ru/index.php(43): MediaWiki->run()
#12 {main}