Discuz! info: Can not connect to MySQL server

Time: 2018-10-20 5:00am
Script: /breast-cancer-stages-importance-of-knowing-breast-cancer-stages-by-michael-lee-t51817.html

Error: Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (2)
Errno.: 2002

Similar error report has beed dispatched to administrator before.