SQL-DATABASE ERROR

Database error in WoltLab Burning Board (): Link-ID == false, connect failed
mysql error: php_network_getaddresses: getaddrinfo failed: Name or service not known
mysql error number: 2002
mysql version: unknown
php version: 5.6.33
Date: 18.02.2018 @ 23:18
Script: /aiboard/thread.php?postid=31756
Referer: